087072_07_UIR_EN

Prévia do material em texto

The Drive & Control Company
Rexroth PSI 6xxx
UI regulation and monitoring
Edition 07Description of application
1070087072
1070087072 / 07Bosch Rexroth AG PSI 6xxx |2�/�138
The data indicated below is intended to describe the
product. Should information on its use be provided,
such information represents application examples
and suggestions only. Catalog specifications shall
not be deemed as warranted quality. 
This information does not release the user from per­
forming his own assessments and verifications. 
Our products are subject to natural wear and aging.
© This manual is the exclusive property of Bosch
Rexroth AG, Germany also in the case of intellec­
tual property right applications.
Reproduction or distribution by any means subject to
our prior written permission.
An example configuration is shown on the cover
page. The delivered product may therefore deviate
from the picture.
Language version of the document: EN
Original language of the document: DE
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 3�/�138
Contents
Contents
1 Regarding this documentation 5. . . . . . . . . . . . . . . . 
1.1 Validity of the documentation 5. . . . . . . . . . . . . . . . . . . . . . . . . . . 
1.2 Additional documentation 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
1.3 Presentation of information 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
1.3.1 Safety instructions 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
1.3.2 Icons 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
1.3.3 Designations 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
1.3.4 Abbreviations 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
2 Safety instructions 9. . . . . . . . . . . . . . . . . . . . . . . . . . 
3 General information on damage to property and
products 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
4 Scope of delivery 13. . . . . . . . . . . . . . . . . . . . . . . . . . . 
5 General information on the „UI regulation“ option 15
5.1 Functions and options 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
5.2 Requirements 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
5.3 Information on assembly and connection 18. . . . . . . . . . . . . . . . . 
5.3.1 ... for PSI 6x00 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
5.3.2 ... for PSI 6xCx 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
5.3.3 Voltage tapping 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
5.4 Firmware modifications 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
5.5 Display of software version 23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
5.6 Update Controller mode ALU/Steel electrode specific 24. . . . . . 
6 Basics on resistance characteristic 25. . . . . . . . . . . . 
6.1 „Normal“ weld 26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
6.2 Welds with insulating materials 30. . . . . . . . . . . . . . . . . . . . . . . . . . 
6.3 Welds with expulsion 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
7 Commissioning of UI regulation 33. . . . . . . . . . . . . . . 
7.1 Basic requirements 33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
7.2 Determining the basic welding parameters 34. . . . . . . . . . . . . . . . 
7.3 Generating reference curves 41. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
7.3.1 Requirements 41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
7.3.2 Defining the resistance characteristic as reference curve 43. . 
7.3.3 Recording by recorder 45. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
7.4 Activating UI regulation 53. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
7.4.1 Description of the most important UI parameters 54. . . . . . . . . 
7.4.2 Special features for activated UI regulation 59. . . . . . . . . . . . . . 
7.5 Deactivating the UI regulation 61. . . . . . . . . . . . . . . . . . . . . . . . . . . 
8 UI monitoring parameters 63. . . . . . . . . . . . . . . . . . . . 
8.1 Available parameters 63. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
8.2 Information on the use of monitoring variables 67. . . . . . . . . . . . 
8.3 Procedure for commissioning 69. . . . . . . . . . . . . . . . . . . . . . . . . . . 
1070087072 / 07Bosch Rexroth AG PSI 6xxx |4�/�138
Contents
8.4 Deactivating UI monitoring 72. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
8.5 Dynamic tolerance band adjustment 76. . . . . . . . . . . . . . . . . . . . . 
8.5.1 Relevant parameters 76. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
8.5.2 Determination of the required parametrization 78. . . . . . . . . . . 
9 For quick information 81. . . . . . . . . . . . . . . . . . . . . . . . 
9.1 Status of the UI functionality 81. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
9.1.1 "Overview" topic, "Overview" tab 81. . . . . . . . . . . . . . . . . . . . . . . 
9.1.2 PSQ status display 82. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
9.2 Actual values determined for the last welding schedule 83. . . . . 
9.3 Curve characteristics of the last 64 welds of a timer 84. . . . . . . . 
9.4 Spot/expulsion overview 85. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
9.5 Display of the PSF, UIP and FQF process variables 86. . . . . . . 
9.6 UIR process overview 89. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
10 Q Stop (Quality Stop) 91. . . . . . . . . . . . . . . . . . . . . . . . 
10.1 Program-specific Q Stop 91. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
10.2 Component-specific Q Stop 92. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
10.3 Exceptions 93. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
10.4 Special spots 93. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
10.5 Configuration 93. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
11 Adhesive function 95. . . . . . . . . . . . . . . . . . . . . . . . . . . 
11.1 Required parameter setting 97. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
11.2 Activation/deactivation of the adhesive function 98. . . . . . . . . . . 
12 Static gun resistance compensation 99. . . . . . . . . . . 
12.1 Setting of the gun resistance compensation 100. . . . . . . . . . . . . . 
12.2 Activating the gun resistance compensation 104. . . . . . . . . . . . . . 
12.3 Procedure after a gun replacement 104. . . . . . . . . . . . . . . . . . . . . . 
12.4 Special cases 107. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
13 Thin-sheet function 111. . . . . . . . . . . . . . . . . . . . . . . . . . 
13.1 Required parameter setting 111. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
13.2 Activating/deactivating the thin-sheet function 112. . . . . . . . . . . . . 
13.3 Thinsheet with stepper 113. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
14 Force monitoring 115. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
14.1 Required parameter setting 117. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
14.2 Activation/deactivation of the force monitoring 120. . . . . . . . . . . . 
14.3 Force monitoring in measuring loop check (with UIR V414) 121. 
15 The „hot-staking“ mode 123. . . . . . . . . . . . . . . . . . . . . . 
15.1 Required parameter setting 123. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
15.2 Switchingthe „hot-staking“ mode on/off 124. . . . . . . . . . . . . . . . . . 
16 Sheet Thickness Combination (STC) 125. . . . . . . . . . 
16.1 Using the STC function 125. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
17 List of tables 127. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
18 List of figures 129. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
19 Abbreviations 131. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
20 Index 135. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 5�/�138
Regarding this documentation
1 Regarding this documentation
This chapter includes important information on the use of the docu­
mentation.
� Inform yourself about the product before you work with it!
1.1 Validity of the documentation
The present documentation
• applies to 
the „UI regulation“ option of the PSI 6xxx weld timers
• is designed for 
Planning, assembly personnel, operators, start-up, service techni­
cians, plant operators.
• provides information about
• Assembly (only needed for the PSQ 6000 XQR module)
• Electr. connection of the required sensors
• UI measurement, regulation, monitoring
• Additional functions which are based on UI measurement, regula­
tion and monitoring
• Activating and deactivating individual functions
1.2 Additional documentation
Several documents are available for the product which are needed to­
gether for comprehensive information.
� Only start the product when you are at least familiar with and under­
stand the documents marked with �.
Table�1: Necessary and supplementary documents
Title Doc. no. Document type
� PSI 6xxx: Weld timer with medium-
frequency inverter
1070080028 Operating instruc­
tions
� PSI 6xxx.xxx xx: Weld timer with
medium-frequency inverter, type-
specific supplement
depending
on type
Operating instruc­
tions (type-spe­
cific supplement)
� PSG xxxx: MF welding trans­
formers
1070087063 Operating instruc­
tions
BOS 6000 online help 1070086446 Reference
PSI 6xxx: Process regulation and
monitoring for aluminium spot wel­
ding
R911172835 Description of ap­
plication
�: required document
For which product?
Target group?
Topics dealt with?
1070087072 / 07Bosch Rexroth AG PSI 6xxx |6�/�138
Regarding this documentation
1.3 Presentation of information
We use uniform icons, terms and abbreviations in this documentation.
They will be explained in the following paragraphs.
1.3.1 Safety instructions
Safety instructions call your attention specifically to danger potentials or
risks.
We distinguish among the following places where safety instructions
may be required:
• Basic safety instructions:
They are related to general important matters and apply to the com­
plete documentation.
You will find these safety instructions in Section 2 and 3 of the
„PSI 6xxx: Weld timer with medium-frequency inverter“ operating in­
structions (Doc. no.�1070080028; also refer to page 5).
• Preceding safety instructions:
They refer to topic-related matters and are provided at the beginning
of a chapter or at the beginning of a whole procedure.
• Integrated safety instructions:
They are related exactly to a separate procedure step and are
provided right before the relevant step within the procedure.
A safety instruction is always structured as follows:
• Warning sign (only in case of personal injury)
• Signal word to indicate the danger level
• Type and source of danger
• Consequences of failure to observe
• Action for averting danger.
Table�2: Example for the structure of a safety instruction
Warning sign + SIGNAL WORD
Type and source of danger!
Consequences of failure to observe!
� Action for averting danger!
� Further action(s) for averting danger.
Integrated safety instructions may be embedded in the format of the
environment so that no ”visual” break in the action sequence is pro­
voked. Therefore they do not necessarily use the layout shown in the
example but they do use the indicated structure.
Where?
Structure?
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 7�/�138
Regarding this documentation
The safety instructions are classified into danger levels (danger
classes). The signal word represents the danger level.
Table�3: Danger classes according to ANSI Z535.6
Signal word Meaning
DANGER Dangerous situation where death or serious physical injuries
will occur if it is not avoided.
WARNING Dangerous situation where death or serious physical injuries
may occur if it is not avoided.
CAUTION Dangerous situation where light to moderate physical injur­
ies may occur if it is not avoided.
NOTICE Situation where damage to property or the environment may
occur if it is not avoided.
Table�4: Examples for classification of safety instructions
DANGER
Type and source of danger!
Consequences of failure to observe!
� Action for averting danger.
WARNING
Type and source of danger!
Consequences of failure to observe!
� Action for averting danger.
CAUTION
Type and source of danger!
Consequences of failure to observe!
� Action for averting danger.
NOTICE
Type and source of danger!
Consequences of failure to observe!
� Action for averting danger.
Danger levels?
1070087072 / 07Bosch Rexroth AG PSI 6xxx |8�/�138
Regarding this documentation
1.3.2 Icons
The following icons are used to mark text passages specifically.
Table�5: Icons used
Icon Meaning
This icon indicates a tip or an information. It helps use
and operate the product optimally or understand the
context better.
� This icon indicates the need to observe/perform certain
things.
• This icon indicates an (unsorted) list.
1.
2.
3.
This icon indicates a (sorted) list or specific procedure
steps where a certain sequence has to be observed.
1.3.3 Designations
The following designations may appear in our documentation:
Table�6: Designations
Designation Meaning
BOS Welding user interface
PE Protective Earth. PE conductor.
PG Programming terminal/welding computer.
PLC Programmable Logic Controller.
PSG Transformer-rectifier unit for PSI types.
Medium-frequency welding transformer 1000 Hz
PSI Programmable weld timer with inverter.
PSQ 6000
XQR
Plug-in module for PSI with UI controller functionality.
Is not needed for PSI 6xCx types.
PST Programmable weld timer with thyristor power unit.
WT Weld timer. 
Also referred to as timer, module or resistance weld timer.
1.3.4 Abbreviations
Refer to Section 19 from page 131.
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 9�/�138
Safety instructions
2 Safety instructions
� Please note the section with the identical name in the operating in­
structions "PSI 6xxx: Weld timer with medium-frequency inverter"
(for doc. no. refer to table on page 5).
1070087072 / 07Bosch Rexroth AG PSI 6xxx |10�/�138
Safety instructions
Notes:
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 11�/�138
General information on damage to property and products
3 General information on damage to property and
products
� Please note the section with the identical name in the operating in­
structions "PSI 6xxx: Weld timer with medium-frequency inverter"
(for doc. no. refer to table on page 5).
1070087072 / 07Bosch Rexroth AG PSI 6xxx |12�/�138
General information on damage to property and products
Notes:
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 13�/�138
Scope of delivery
4 Scope of delivery
� Please note the section with the identical name in the operating in­
structions "PSI 6xxx: Weld timer with medium-frequency inverter"
(for doc. no. refer to table on page 5).
1070087072 / 07Bosch Rexroth AG PSI 6xxx |14�/�138
Scope of deliveryNotes:
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 15�/�138
General information on the „UI regulation“ option
5 General information on the „UI regulation“ option
5.1 Functions and options
What does the UI controller do?
It ensures
• in the sequence modes ”Single spot” (robot) and ”Repeat” (manual
guns)
• during the 2nd current block
• that the required amount of heat is supplied to the spot weld.
PreWLD and PstWLD are frequently used for „special tasks“.
Whereas a PstWLD used is always executed as programmed even if
the UI controller is active, a programmed PreWLD influences the
control process of the weld. For more information, please refer to the
section „Instructions on welds with preliminary impulse (PreWLD) on
page 28.
How does this work?
1. Based on a faultless welding in KSR mode, the system determines
the curve of the process variables voltage and current as a function
of time to calculate the resistance characteristic.
For basic information on the resistance characteristic during a weld,
please refer to Section 6 from page 25.
2. Ideally on the basis of several resistance characteristics obtained in
this manner, a mean curve (reference curve) is created for a spot
weld.
3. Based on the reference curve, the UI controller is able to change the
amount of current and weld time of the 2nd current block so that the
learned amount of heat will be supplied to the spot weld securely
even if different interfering variables occur.
NOTICE
Simultaneous welds at the same component
Voltages and currents which are coupled into the measuring pro­
cess from outside may simulate a disturbed welding process. This
may lead to unnecessary controller interventions.
� Always avoid situations where several spots are welded within a
short distance on the same component simultaneously.
What interfering variables can be compensated?
• Electrode wear
• Bad caps
• Different sheet thicknesses / additional sheet
• Different coatings
1070087072 / 07Bosch Rexroth AG PSI 6xxx |16�/�138
General information on the „UI regulation“ option
• Force changes
• Mains voltage changes
• Shunt circuits
• Bad contacts
• Glue
• Bad fit
Benefits / advantages of the „UI regulation“ option?
• Very broad range of interfering variables can be compensated
• Considerably fewer user interventions necessary when interfering
variables occur
• Better and more precise monitoring of your welding process by a
large variety of monitored parameters (refer to Section 8 from
page 63).
• Simple and rapid parametrization of the monitoring functions by
graphic representation of the actual value distribution over time (his­
togram display. Refer to page 71).
• Additional functions building on the options provided by UI regula­
tion and monitoring help improve your welding quality (e.g. adhesive
function, thin sheet function, gun resistance compensation, Q stop
logic, force monitoring)
5.2 Requirements
• For PSI 6x00:
UI controller module (PSQ 6000 XQR).
Information on the required slot, displays and connections of the
module is provided in the operating instructions „ PSI 6xxx: Weld
timer with medium-frequency inverter“ (doc. no. � 1070080028; also
refer to page 5).
• For PSI 6xCx: 
Licence Memory Card (Micro SD memory card) with the correspond­
ing option.
Information on the installation/removal of the Licence Memory Card
is provided in the operating instructions „PSI 6xxx: Weld timer with
medium-frequency inverter“ (doc. no. 1070080028; also refer to
page 5).
Information on all options stored in the License Memory Card can be
displayed via BOS in the „Diagnosis“ topic „License“ tab.
• Primary or secondary current measurement with functioning sensor
technology.
• Correctly wired voltage tapping at the gun arms (refer to Section
5.3.3 from page 20).
• Matching XQR firmware version.
If required, we will provide firmware updates to optimize, improve or
expand the product's mode of functioning. Therefore, the present
documentation may describe functions, which require an update of
the XQR firmware. For details, refer to Section 5.4 page 22.
• Use of the BOS user interface for parametrization and visualization.
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 17�/�138
General information on the „UI regulation“ option
Information on the BOS 6000 user interface is provided in the
„BOS 6000 online help“ (doc. no.�1070086446; also refer to page 5).
1070087072 / 07Bosch Rexroth AG PSI 6xxx |18�/�138
General information on the „UI regulation“ option
5.3 Information on assembly and connection
5.3.1 ... for PSI 6x00
When a new weld timer is delivered, the matching timer firmware has
already been integrated and the UI controller module (PSQ 6000 XQR)
built in as ordered option.
Please note in this case:
Information on displays and connections are provided in the operat­
ing instructions „PSI 6xxx: Weld timer with medium-frequency in­
verter“ (doc. no. 1070080028; also refer to page 5).
1. If you wish to use secondary current measurement, a matching cur­
rent sensor has to be installed in the secondary circuit and wired cor­
rectly.
2. A voltage tapping has to be installed at the gun arms and wired cor­
rectly (refer to Section 5.3.3 from page 20).
3. Use BOS to set the „Current measurement“ parameter correctly un­
der the „Programming“ topic „General“ tab.
4. Check whether, after selection of the relevant weld timer, the „PSQ“
tab is displayed under the „Programming“ and „Diagnosis“ topic, the
„UIR setup“ tab is displayed under the „Settings“ topic and the „UIR
mode“ option group is displayed under the „Overview“ topic.
If that is the case, the UI controller module was detected by the timer
firmware and can now be parametrized using the BOS.
If that is not the case, please write down the software edition of your
• BOS (via BOS 6000 title bar)
 and contact our Service.
Proceed as follows to retrofit a weld timer:
1. Switch off the 24 VDC logic supply of the weld timer.
2. Remove blanking plate at the corresponding slot.
3. Insert the UI controller and tighten it.
Information on the required slot, displays and connections of the
module is provided in the operating instructions „PSI 6xxx: Weld
timer with medium-frequency inverter“ (doc. no. 1070080028; also
refer to page 5).
4. If you wish to use secondary current measurement, a matching cur­
rent sensor has to be installed in the secondary circuit and wired cor­
rectly.
5. A voltage tap has to be installed at the gun arms and wired correctly
(refer to Section 5.3.3 from page 20).
6. Switch on the 24 VDC logic supply of the WT.
The weld timer now has to start up without any errors.
7. Use BOS to set the „Current measurement“ parameter correctly un­
der the „Programming“ topic, „General“ tab.
8. Check whether, after selection of the relevant weld timer, the „PSQ“
tab is displayed under the „Programming“ and „Diagnosis“ topic, the
„UIR setup“ tab is displayed under the „Settings“ topic and the „UIR
mode“ option group is displayed under the „Overview“ topic.
When a new weld timer is de­
livered
When the WT is retrofitted
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 19�/�138
General information on the „UI regulation“ option
If that is the case, the UI controller module was detected by the weld
timer firmware and can now be parametrized using the BOS.
If that is not the case, please write down the software edition of your
• weld timer (via BOS 6000, „Diagnosis“ topic, „WT information“
tab) and
• BOS (via BOS 6000 title bar)
 and contact our Service.
5.3.2 ... for PSI 6xCx
When a new weld timer is delivered, the matching timer firmware and
the necessary License Memory Card has already been integrated.
Please note in this case:
1. If you wish to use secondary current measurement, a matching cur­
rentsensor has to be installed in the secondary circuit and wired cor­
rectly.
2. A voltage tap has to be installed at the gun arms and wired correctly
(refer to Section 5.3.3 from page 20).
3. Use BOS to set the „Current measurement“parameter correctly un­
der the „Programming“ topic, „General“ tab.
4. Check whether, after selection of the relevant weld timer, the „PSQ“
tab is displayed under the „Programming “ and „Diagnosis“ topic, the
„UIR setup“ tab is displayed under the „Settings“ topic and the „UIR
mode“ option group is displayed under the „Overview“ topic.
If that is the case, the Option „UI regulation“ option was detected by
the timer firmware and can now be parametrized using the BOS.
If that is not the case, please write down the software edition of your
• BOS (via BOS 6000 title bar)
 and contact our Service.
Proceed as follows to retrofit a weld timer:
1. Switch off the 24 VDC logic supply of the weld timer.
2. Remove the operating unit of the diagnosis module.
3. Slide the License Memory Card with the activated option into the
Micro SD slot.
Information on the installation/removal of the Licence Memory Card
is provided in the operating instructions „PSI 6xxx: Weld timer with
medium-frequency inverter“ (doc. no. 1070080028; also refer to
page 5).
Information on all options stored in the License Memory Card can be
displayed via BOS in the „Diagnosis“ topic „License“ tab.
4. Plug the operating unit of the diagnosis module on again.
5. If you wish to use secondary current measurement, a matching cur­
rent sensor has to be installed in the secondary circuit and wired cor­
rectly.
6. A voltage tap has to be installed at the gun arms and wired correctly
(refer to Section 5.3.3 from page 20).
7. Switch on the 24 VDC logic supply of the weld timer.
The weld timer now has to start up without any errors.
When a new weld timer is de­
livered
When the WT is retrofitted
1070087072 / 07Bosch Rexroth AG PSI 6xxx |20�/�138
General information on the „UI regulation“ option
8. Use the BOS to set the „Current measurement“ parameter correctly
under the „Programming“ topic, „General“ tab.
9. Check whether, after selection of the relevant weld timer, the „PSQ“
tab is displayed under the „Programming“ and „Diagnosis“ topic, the
„UIR setup“ tab is displayed under the „Settings“ topic and the „UIR
mode“ option group is displayed under the „Overview“ topic.
If that is the case, the Option „UI regulation“ option was detected by
the timer firmware and can now be parametrized using the BOS.
If that is not the case, please write down the software edition of your
• weld timer (via BOS 6000, „Diagnosis“ topic, „WT information“
tab) and
• BOS (via BOS 6000 title bar)
 and contact our Service.
5.3.3 Voltage tapping
The voltage signal measured is influenced by the properties of the
transformer, the temperature rise in the secondary cables and flexible
links and their wear due to movement. 
Since these interfering variables hardly exist on the gun arms, it is re­
commendable to connect the voltage measuring cables there.
The closer the voltage tap is positioned to the electrodes/shafts, the
smaller the influence of the gun resistance on control and monitoring
processes.
In this context, using the „Gun resistance compensation “functional­
ity is also useful (see from page 99).
Basic information concerning compliant designs is provided in
standard EN 60204-1: (Safety of machinery - Electrical equipment of
machines - part 1: „General requirements“ - Section 13.4.3: Connec­
tion to moving elements of the machine).
Shielded cable (max. 100 m)
Welding transformer
Highly flexible cable
(max. 1 m)
Fig.�1: Voltage tapping
� Always install the voltage tapping behind the secondary cable or
flexible links (looking toward the electrodes).
� Please note that if the UI controller module PSQ 6000 XQR is used in
connection with PSI 6x00, the polarity of the voltage tapping line is
not random.
Therefore determine the polarity for all guns uniformly!
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 21�/�138
General information on the „UI regulation“ option
� Connect voltage measuring cables on the gun arm permanently and
with low impedance by clamping a suitable cable lug under an exist­
ing screwed connection.
� Where the voltage measuring cables are moved by the gun, use
highly flexible cable with 0.5 to 1.5 mm2 cross-section. As only one
core is connected to each gun arm, the cable may be unshielded in
this area over a length of approx. 1 m. 
From there, and before the voltage cable is routed together with
other cables, shielded cables must be used for further routing.
� The shield of the voltage measuring cable must be routed to the weld
timer - also through further plugged connections - and must be ex­
clusively connected at the entry to the control cabinet/Schweisskof­
fer or on the weld timer side, respectively, to frame potential using a
thoroughly conductive, large area connection.
� A plugged or clamped connection is useful at the connection point
between unshielded and shielded cables for easy replacement of
voltage measuring cables.
� Always install the voltage measuring cables so as to ensure that the
movement of the gun is not obstructed and the cables are not dam­
aged.
� The cable's permitted bending radius must be observed in the mov­
ing points.
� Please ensure sufficient strain relief and fastening of the cable.
Connection of the voltage measuring cables to the WT:
for PSI 6x00: X8A (at the UI controller module „PSQ 6000 XQR“) 
for PSI 6xCx: X3
Information on the corresponding terminal assignments is provided
in the operating instructions „PSI 6xxx: Weld timer with medium-fre­
quency inverter“ (doc. no. 1070080028; also refer to page 5).
Suitable cables and ring terminals
• For use in the area of the gun or gun arm:
• Unshielded cable, e.g. single leads of the type „Ölflex Heat
205 SC“ Messrs. Lapp
• Solistrand ring terminals made from electrolytically tin-plated cop­
per (e.�g. type 34124 Messrs. Tyco Amp)
• For use in the remaining area:
• shielded cable, 2 x 0.75 mm2, twisted pair
(corresponding to part no.:1070 913 494:
consisting of 2 x 2 x 0.75 mm2, LiYCY; 2 pairs of cores for elec­
trode voltage and current sensor signal)
1070087072 / 07Bosch Rexroth AG PSI 6xxx |22�/�138
General information on the „UI regulation“ option
5.4 Firmware modifications
Update XQR controller version from V411 to V412
• New monitoring with respect to mechanical gun defect
• New monitoring with respect to oscillating current
• New sequence (schedule) abortions and fault messages in the case
of contact monitoring (R > 3 mOhm) and data inconsistency
(between programmed KSR sequence and UI reference curve char­
acteristic)
• Reweld now also possible in the UI mode (measured or controlled)
• New start-up function „STC“
• New start-up function „Iterative setup“
• New PSF evaluation for aluminum operating mode
Update XQR controller version V413
• Display of software version in BOS 6000 only for PSI6XCX for exam­
ple V413.01 (refer to Section 5.5)
• Monitoring function „mechanical gun defect“ and „swinging current“
can be parameterized (electrode parameter).
• New Monitoring function „electrode pick up“ only for PSIXCX in
mode ALUMINIUM.
• Toleranceband for „Test gun resistance“ (Gun resistance change)
can be programmed in absolute values (in μOhm).
• Identification of reference curve is stored in weld current log (STC
name)
Update XQR controller version V414
• Spatter detection for Aluminium adapted.
• Adaption coefficients for Q­Factors (UIP, FQF, PSF) implemented
(refer to BOS Help Programming: PSQ: UIR Monitoring Adapt.
Q-factor since BOS V1.45.1 ).
• Automatic spot repetition by violation of absolute tolerance bands of
Q­factors possible (referto BOS Help Programming: PSQ: UIR
Monitoring Abs. Reweld Act. since BOS V1.45.1).
• Measuring loop check force extended. Check on a force tolerance
band.
• Revision of monitoring function „Electrode pick up“ for mode Alu­
minium.
• Revision of the calculation function for the resistance contact moni­
toring.
• Mode version "Hot Staking" with stepper.
• New special combination "Thin sheet with stepper" (refer to Section
13.3).
• Reference value of PHA is automatically written when gun
resistance is scaled by the robot interface.
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 23�/�138
General information on the „UI regulation“ option
5.5 Display of software version
The controller version has been extended with index .00 to .99 . The
index for example .00 signalize the versions step from e.g. 41x to
41x+1.
The old controller version could be identified only with the date of the
release. In the new display the Controller version can be recognized.
With the description of the Controller version (refer to Section 5.4) the
differences to the previous version can be detected.
Fig.�2: Controller Software Version
1070087072 / 07Bosch Rexroth AG PSI 6xxx |24�/�138
General information on the „UI regulation“ option
5.6 Update Controller mode ALU/Steel electrode specific
With controller version 414 the mode Aluminiumor / Steel can be selec­
ted electrode specific.
This works only for special timer types which have additional the firm­
ware with controller version 414. That are for example the types
PSI6XCX.232, 633 and 732 (refer to fig. 3).
Required is a license for UI controller and a license for Aluminium.
Fig.�3: Mode Aluminium/Steel electrode specific
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 25�/�138
Basics on resistance characteristic
6 Basics on resistance characteristic
The UI controller uses very different types of information from the weld­
ing process to perform its regulation tasks. At various times during the
welding process, it scans different measured quantities to calculate the
„current“ and „weld time“ as influencing variables. Thus, it considers not
only the current, but also the energy and the resistance. Furthermore, it
considers information concerning expulsion and the temporal relation­
ship of the individual quantities for regulation.
For a better understanding of the process of a welding task, it is helpful
to know more about the resistance characteristics.
These characteristics can be visualized using the BOS user inter­
face, e.g. under the "Diagnosis" topic, "PSQ" tab. Detailed informa­
tion on all available display functions are provided via the BOS online
help.
Current
Voltage
Resistance
C
u
rr
e
n
t
V
o
lt
a
g
e 
/ 
R
e
s
is
ta
n
c
e
Fig.�4: Example: Current, voltage and resistance characteristic
With constant-current regulation mode (KSR) active, this visualiza­
tion may be used to monitor process changes after a variation of the
welding parameters and these findings may be used for further op­
timization.
When the UI controller is active, this visualization can be used to de­
tect controller interventions and changes in the process situation.
PreWLD and PstWLD are frequently used for „special tasks“.
Whereas a PstWLD used is always executed as programmed even if
the UI controller is active, a programmed PreWLD influences the
control process of the weld. For more information, please refer to the
section „Instructions on welds with preliminary impulse (PreWLD)“
on page 28.
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Basics on resistance characteristic
6.1 „Normal“ weld
The resistance drops from relatively high values at the beginning of the
weld because the sheets warm up and are therefore closer connected.
This phase is referred to as the „coupling or „heating phase“.
After a relative minimum, the resistance rises again to a relative max­
imum due to the beginning liquefaction of the material in the spot to be
welded.
When the maximum is reached, the material in the spot to be welded is
liquid. The resistance value drops continuously until the end of the weld
time. During this phase, the spot to be welded grows to the spot dia­
meter to be reached.
Separate regulation algorithms have been implemented for the
coupling and melting phase.
Coupling /
heating phase
Melting phase/
spot growth
Maximum
Resistance (in mOhm)
Weld time (in ms)
Fig.�5: Resistance characteristic of an undisturbed weld
Optimally, the current and the weld time as well as the force must be
chosen so as to ensure that the relative maximum of the resistance
characteristic occurs before one-half of the weld time has elapsed. 
With hot-galvanized material, the coupling phase is longer, therefore
the maximum resistance characteristic may also be in the 2nd third
of the weld time.�
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 27�/�138
Basics on resistance characteristic
• After start of the welding schedule, the regulation of the coupling first
begins at the time „1ms“. 
In this phase, the current adjustment permitted for the controller is
limited to +/- 5%.
• At what point the switch to melting regulation occurs is determined
by the weld timer automatically when the reference curve is loaded,
on the basis of the reference curve. 
The point in time determined can be found via BOS6000 in the „Pro­
gramming“ topic, „PSQ“ tab, „UIR“ subtab under „Beginning of regu­
lation“ (see Section 7.4.1 from page 54), if the „Regulation (P)“
parameter has been set to ON.
With respect to the resistance curve shown in Fig. 5:, the „Beginning
of regulation“ is always located somewhat before the relative max­
imum for internal optimization reasons.
The automatic system for determination of the time for changing
between coupling and melting regulation can be adjusted, if needed,
using the „Start manual regulation“ parameter. For more information
on this topic, please refer to the „Start manual regulation“ parameter
description on page 56.
• During the melting phase, the current adjustment permitted for the
controller is limited to the settings of the „max. current increase“ and
„max. current reduction“ parameters (refer to page 56).
• The melting regulation ends at the end of MainWLD - except when a
down slope time is used (refer to page 29).
• If a weld time prolongation is permitted, the weld timer calculates the
weld time prolongation at the end of melting regulation and executes
this time with the last current value of the melting regulation.
 
It must be pointed out here that the characteristic shown in Fig. 5: rep­
resents an ideal curve for interpretation. Such dynamic resistance char­
acteristics (i.e. resistance changes of approx. 100 μOhm) are usually
obtained with thick sheet combinations.
There may certainly be some sheet combinations where minimums and
maximums are not too distinct, therefore, the curve has a very flat char­
acteristic. This is the case, e.�g. for very thin sheet combinations or pre­
cision-spot welding.
It is even possible that the resistance characteristic - starting with a high
initial value - simply declines without any detectable extremes until the
end of the weld time. This phenomenon can be observed with thin elec­
trogalvanized sheets. The controller can work with these characterist­
ics, however, they are more difficult to interpret.
The "Thin-sheet" function is available for thin sheets (less 1�mm per
sheet). Refer to section 13 from page 111.
Important information in con­
nection with the regulation
phases
No maximum or only a weak
maximum visible?
1070087072 / 07Bosch Rexroth AG PSI 6xxx |28�/�138
Basics on resistance characteristic
Instructions on welds with a preliminary impulse (PreWLD)
If the PreWLD has been programmed, it is used for regulationof the
coupling phase. This prolongs the time available for regulation of the
melting phase and gives the controller more leeway for the compensa­
tion of interfering variables.
� Therefore, make sure that no melting takes place during the
PreWLD. During this preliminary impulse, the resistance character­
istic must not yet reach its maximum.
This is achieved by the corresponding amount of current (1. %I) and im­
pulse duration (PreWLD) and a possible cool time (1.CT). The max­
imum and the falling edge of the resistance curve must be completely
within the main impulse (MainWLD).
PreWLD MainWLD1.
CT
Resistance (in mOhm)
Weld time (in ms)
Fig.�6: Correct weld with preliminary impulse
Notes on multiple impulse welds
If several impulses are used within MainWLD, this has no effect on the
time ranges of the regulation phases.
However a special feature occurs when the regulation continues after a
2nd Cool time: 
since this part of the process can be interpreted as a new coupling
phase, the system executes the welding process without adaptive reg­
ulation for 30� ms initially, before the regulation sets in again.
The entire regulation time available is thus reduced the larger the num­
ber of impulses and the smaller the weld time of the impulses (Main­
WLD!).
� In case of multiple impulse welding, make sure that the resistance
maximum is already reached in the first impulse of MainWLD.
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 29�/�138
Basics on resistance characteristic
� Make sure that the programmed impulse time (MainWLD) is not too
short. Sufficient time must remain for melting.
A maximum resistance building up via two consecutive impulses is
not optimal.
Notes on welds with upslope (UST)
The regulation for the melting phase begins no earlier than after the
UST. This
• prolongs the coupling phase by the UST,
• reduces the regulation time for the melting phase,
• influences the weld time prolongation (if permitted).
Notes on welds with down slope (DST)
The regulation for the melting phase already ends with the beginning of
the DST. This
• reduces the regulation time for the melting phase by the DST,
• does not influence the regulation time for the coupling phase,
• influences the weld time prolongation (if permitted).
1070087072 / 07Bosch Rexroth AG PSI 6xxx |30�/�138
Basics on resistance characteristic
6.2 Welds with insulating materials
Especially when using adhesives, insulating layers are encountered
between the sheets to be welded. When used properly, these materials
do not present an obstruction to the weld. However, their insulating ef­
fect first has to be overcome before welding can start.
At the beginning of the weld time, resistance remains high until the insu­
lating layer is driven out or has been burnt off. The duration of this phase
depends on the material used and the electrode gun force, among oth­
ers.
When the insulation has been removed, the weld will be executed as
normal, and the resistance characteristics will be determined by the
sheet combination.
Delayed beginning of the heating phase due to adhesive
Resistance (in mOhm)
Weld time (in ms)
Normal characteristic
Fig.�7: Resistance characteristic of welds with an adhesive
The "Adhesive function" is available for welded joints using an ad­
hesive between the sheets involved. Refer to section 11 from
page 95.
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 31�/�138
Basics on resistance characteristic
6.3 Welds with expulsion
Expulsion can be detected by a sudden change towards lower resist­
ance values in the resistance characteristic.
Expulsion
Resistance (in mOhm)
Weld time (in ms)
Fig.�8: Resistance characteristic with expulsion at 105 ms
When the system should interpret this kind of change as expulsion
can be parametrized in the "Programming" topic, "PSQ" tab, "UIR"
subtab via the "Detection of expulsions" and "Expulsion decay time"
parameters.
When the system detects an expulsion, it displays the expulsion
symbol incl. the time the expulsion occurred if UI measurement has
been activated for the respective weld:
Although the UI controller compensates many interferences, expul­
sions can nevertheless occur during active UI regulation. The cause
may be the occurrence of a single very strong interference as well as the
interaction of several interference variables.
The controller's response to expulsions can be set with regard to cur­
rent in the "Programming" topic, "PSQ" tab, "UIR" subtab via the "Ex­
pulsion current control" parameter. 
With regard to time an active UI regulation automatically extends the
weld time to a certain extent in order to make up for the energy lost in
the material.
Expulsion symbol
with time expulsion occurred
1070087072 / 07Bosch Rexroth AG PSI 6xxx |32�/�138
Basics on resistance characteristic
The active UI controller furthermore offers the possibility of varying
the energy input through %I correction. A spot-weld-related lowering
the heat may thus also be used for the temporary "manual" elimina­
tion of expulsion.
For the optimization of welds with expulsion, it is helpful to know the time
the expulsion occurred. Several options to avoid expulsion can be de­
rived:
� Avoid edge welds. Spot position has to be optimized, if necessary.
� In case of unresolvable fitting problems, use an upslope. This im­
proves coupling.
� Check whether the programmed ratio of current to force is correct.
� If force is within the correct range, reduce the current.
� Check whether the repositioning behavior of the welding system is
ok.
� If the expulsion occurs just before the end of the weld time - espe­
cially with hot galvanized material - reduce the weld time slightly.
Expulsion
in the 1st and 2nd third of the
weld time
Expulsion
in the last third
of the weld time
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 33�/�138
Commissioning of UI regulation
7 Commissioning of UI regulation
7.1 Basic requirements
• A properly completed basic commissioning of the system. 
Information on this topic is provided in the operating instructions
„PSI 6xxx: Weld timer with medium-frequency inverter“ (no.
1080080028) under Section „Commissioning“.
• The information provided in Section 5.2 and 5.3 (see from page 16).
• Appropriately set transformer, current and force calibration paramet­
ers.
• Perfect condition of gun and electrode shafts.
• Correct cooling conditions at the gun (water tubes, cooling water
quantity, supply temperature).
• The gun forces generated are in accordance with the command value
inputs and are reproducible.
• Correctly positioned electrode tips.
• Electrode tips dressed to fit.
If tip dressing is not possible for a gun, the necessary working surface
of the tip must be ensured by filing or grinding. Thus, the gun's push­
ing movement can be minimized especially if tips are lowered at an
angle.
If a pushing of the gun is still detected after dressing, the electrode
shafts have to be adjusted.
Irregularities on the contact surface (e.g. chatter marks) and deviat­
ing orientations of contact surface and joining plane must be avoided.
• The electrode tips have been worked in without being excessively
worn. Recommendation: tip wear ranges between 15 and 100 welds.
• Welding equipment and parts to be joined must be suitable for the
welding task (forces, positioning, cooling, flange width, etc.).
• Interferences are eliminated or at least reduced to a minimum.
• Matching (KSR) basic parametrization of the respective weld. For
more information on this topic, refer to Section 7.2.
How to generate reference curves is described in Section 7.3 from
page 41.
... especially at the weld timer
... especially at the gun
... generally at the plant
... and additionally for genera­
tion of a referencecurve
1070087072 / 07Bosch Rexroth AG PSI 6xxx |34�/�138
Commissioning of UI regulation
7.2 Determining the basic welding parameters
We recommend to use a separate program for each combination of
different sheet thicknesses and to determine separate reference
curves.
Advantage: when using separate programs, all welding parameters
can be optimally set for the welding task in question and later in the UI
control mode, the weld time will not become longer than necessary
based on the different sheet thicknesses.
In connection with manual guns, a single welding program often has
to cover a fairly wide range of sheet thicknesses and material combin­
ations. Recommendation:
• in the case of total sheet thickness differences of up to 3 mm: 
Determine the (KSR) basic parametrization for the thinnest sheet
combination involved.
• in the case of total sheet thickness differences of more than 3 mm: 
Determine the (KSR) basic parametrization for the medium sheet
combination involved.
In the case of sheet combinations with extreme differences (thin/soft
and thick/higher-strength), we recommend the use of separate weld­
ing programs.
The basic welding parameters of a spot weld to be configured can be ob­
tained from various sources:
• Accepting the welding parameters from a system with the same weld­
ing task that operates reliably
• Results of lab examinations
• DVS tables
• Manufacturer-specific, internal standard
• Calculation programs
• Database of welding parameters
• Simulation programs
The approach chosen in this context is dependent on the existing cir­
cumstances, options and the time frame available.
How basic parameters are determined may have considerable influ­
ence on the later process stability and the scope of possibly required fol­
low-up optimization.
We distinguish between 3 variations in this context:
1. Determination using original component at the production plant.
+ Optimally suited for subsequent generation of reference curves.
+ Special features typical of component/production have little im­
pact on subsequent UI regulation/monitoring (shunt circuit, robot
positioning). This reduces optimization requirements, if any, after
conversion to UI regulation.
+ Very good basis for the UI monitored parameters process stability
(PSF) and process quality (UIP).
+ Influence of dress cycles is taken into account.
This is important should it be necessary later to switch off the UI
regulation (return to KSR mode) temporarily.
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 35�/�138
Commissioning of UI regulation
+ Suitable if sufficient components for determination of the basic
parameters are available.
- High costs due to scrap rate during tests (components).
- Production on the relevant lines is not possible or only with restric­
tions during determination of the basic parameters.
2. Determination using sheet strips on the production plant.
+ Low costs due to scrap during tests.
+ Well-suited if no/few components are available for determining the
basic parameters (e.�g. for new sheet thickness/material combina­
tions).
+ Suitable for subsequent generation of reference curves.
- Special features typical of component/production may have a
great impact on subsequent UI regulation/monitoring (shunt cir­
cuit, robot positioning, wear). This increases optimization require­
ments, if any, after conversion to UI regulation.
- The basis for the UI monitored parameters process stability (PSF)
and process quality (UIP) is not as good compared to the option1.
- Production on the relevant lines is not possible or only with restric­
tions during determination of the basic parameters.
3. Determination using sheet strips in the lab
+ The ongoing production on the relevant lines is not influenced dur­
ing determination of the basic parameters.
+ Low costs due to scrap during tests.
+ Well-suited if no/few components are available for determining the
basic parameters (e.�g. for new sheet thickness/material combina­
tions).
+ Suitable for subsequent generation of reference curves.
- Special features typical of component/production may have a
great impact on subsequent UI regulation/monitoring (shunt cir­
cuit, robot positioning, wear, gun resistance). This increases op­
timization requirements, if any, after conversion to UI regulation.
- The basis for the UI monitored variables process stability (PSF)
and process quality (UIP) is not as good compared to the option 2.,
if the „Gun resistance compensation“ functionality (refer to Sec­
tion 12 from page 99) is not used.
The objective is, in any case, the optimal (KSR) basic parametrization of
the respective weld.
1070087072 / 07Bosch Rexroth AG PSI 6xxx |36�/�138
Commissioning of UI regulation
Procedure
1. Make sure that neither the program-related nor the electrode-related
I% and pressure correction for the spot weld is active.
2. Make sure that a possibly necessary I% stepping for compensation of
the effects of electrode wear is parametrized correctly.
3. Make sure that KSR mode is active for the respective weld.
4. Make sure that automatic reweld is switched off for the respective
weld.
5. Make sure that UI measurement is active for the respective weld
(„Programming“ topic, „PSQ“ tab, „UIR“ subtab: „Measurement (S)“
and „Measurement (P)“ parameters).
6. Make sure that UI regulation and monitoring is deactivated for the re­
spective weld.
7. Determine the required SQZ squeeze time.
It must be chosen so that the programmed force has been completely
built up when the weld time starts. Otherwise, the clear reproducibility
of the resulting resistance characteristic is reduced.
In the example in the figure below, it is clearly shown that the pro­
grammed force is only built up after about 300 ms:
Force (in N)
Time (in ms)
Fig.�9: Example: Force build-up during the squeeze time
For manual guns, a squeeze time of at least 500 ms is generally ap­
propriate.
The squeeze time should be individually verified and adjusted (if ne­
cessary) for each type of gun. Especially if large guns and higher
forces are involved, a longer squeeze time can improve the quality of
the weld.
Squeeze time (SQZ)
1070087072 / 07 Bosch Rexroth AGPSI 6xxx| 37�/�138
Commissioning of UI regulation
Resistance (in μOhm)
Time (in ms)
Resistance char­
acteristic for
Force: 3.0 kN
SQZ: 300 ms
Resistance char­
acteristic for
Force: 3.0 kN
SQZ: 150 ms
Fig.�10: Example: Resistance characteristic with appropriate and in­
sufficient SQZ
8. Determine the HLD Hold time.
The length of the HLD is dependent on the sheet combination. 
Tests have shown that an HLD of 100-200�ms is generally appropri­
ate. 
In the case of higher-strength materials, a longer HLD may be appro­
priate in order to cool the spot weld in a more defined manner.
9. Determine the force, weld time and amount of current (e.g. based on
a table). The following table is suited for
• soft deep-drawn steel
• organic coating
• the use of F16 electrode caps in pairs.
Table�7: Basic welding parameters
Total sheet
thickness (mm)
UST
Upslope
(ms)
MainWLD
Main weld
time (ms)
Amount of
current (kA)
Force
(kN)
1.2 - 200 9.0 2.0
1.3 - 200 9.0 2.1
1.4 - 200 8.9 2.1
1.5 - 210 8.8 2.1
1.6 - 230 8.7 2.2
1.7 - 240 8.7 2.2
1.8 - 250 8.6 2.2
1.9 - 270 8.6 2.3
2.0 100 350 8.5 2.3
2.1 100 360 8.5 2.4
2.2 100 380 8.4 2.4
2.3 100 390 8.4 2.5
2.4 100 400 8.3 2.5
2.5 100 410 8.3 2.6
2.6 100 430 8.2 2.6
Hold time (HLD)
1070087072 / 07Bosch Rexroth AG PSI 6xxx |38�/�138
Commissioning of UI regulation
Total sheet
thickness (mm)
Force
(kN)
Amount of
current (kA)
MainWLD
Main weld
time (ms)
UST
Upslope
(ms)
2.7 100 440 8.2 2.7
2.8 100 450 8.2 2.8
2.9 100 470 8.1 2.9
3.0 120 500 8.1 3.03.1 120 510 8.1 3.1
3.2 120 530 8.0 3.2
3.3 120 540 8.0 3.3
3.4 120 550 8.0 3.4
3.5 120 560 7.9 3.5
3.6 120 580 7.9 3.6
3.7 120 590 7.9 3.6
3.8 120 600 7.8 3.7
3.9 120 620 7.8 3.7
4.0 120 630 7.8 3.8
4.1 120 640 7.8 3.9
4.2 120 660 7.8 4.0
4.3 120 670 7.8 4.1
4.4 120 680 7.8 4.2
4.5 150 710 7.8 4.3
4.6 150 730 7.8 4.4
4.7 150 740 7.8 4.5
4.8 150 750 7.8 4.6
4.9 150 770 7.8 4.6
5.0 150 780 7.8 4.7
5.1 150 790 7.8 4.8
5.2 150 800 7.8 4.8
5.3 150 820 7.8 4.0
5.4 150 830 7.8 5.0
5.5 150 850 7.8 5.1
5.6 150 860 7.8 5.2
5.7 150 870 7.8 5.3
5.8 150 880 7.8 5.4
5.9 150 900 7.8 5.5
6.0 150 910 7.8 5.5
• Notes on Force:
• If several sheet thickness and material combinations have to be
covered by a single welding program (e.�g. for manual guns),
the force for thickest combination to be welded (taking into ac­
count the strength of the sheets) should be used.
• Recommended force increase in relation to the table above:
• for 3-sheet-combinations in dependence on the component
geometry (fitting problems): 10%
• for high-strength steels: 15%
• for ultra-high-strength steels: 20%
• Sometimes, manual guns are only able to build up forces of
3 kN. The force should be set to approx. 95 % of the maximum
gun force in this case (in order to reduce the wear of the gun).
Force
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• Notes on Weld time:
• If several sheet thickness and material combinations have to be
covered by a single welding program (e.�g. for manual guns),
you should use the value for the thinnest sheet stack as weld
time, at least however 250 ms.
• An Upslope from 50 ms to 100 ms is recommended especially
in the event of fitting problems, thick sheet stacks (also for
3-sheet welds) and adhesives.
For manual guns, the upslope values in the table above should
be reduced by half.
For welds with adhesive, the „Adhesive (Glue) function“ is avail­
able (refer to Section 11 from page 95). Important information on
the necessary basic parametrization is provided in Section 11.1
from page 97.
• Notes on Amount of current:
• First optimize the amount of current after correct parametriza­
tion of the required force.
• The welding current should range in the upper third of the weld­
ing range of the selected sheet combination.
• Determine the amount of current so that a maximum resist­
ance, if applicable, occurs in the 1st third of the weld time.
• Take into account the rigidity and coating of the welding mater­
ial.
• For higher-strength steel (especially Usibor), a current re­
duction of up to 1.0�kA from the table value is necessary.
• For electrocoating and hot-dip galvanizing, a current in­
crease of 0.5 to 1.5 kA of the table value is recommended.
• The resulting current density is reduced due to the larger contact
surface. Unless the basic parametrization is already close to the
expulsion limit, the recommended %I (in the table above) should
be increased by 10-20%.
• The current reduction for high-strength steels recommended
above does not apply or has to be distinctly lower.
• For electrocoating and hot-dip galvanizing, a current increase of
1.5 kA of the table value is recommended for total sheet thick­
nesses of up to 2 mm.
10.Perform a test weld with the parameters set and visualize their resist­
ance characteristic.
Information on the resistance characteristic and its visualization is
provided in Section 6 from page 25.
11.Verify the required quality of the welding result by means of destruct­
ive test and ultrasonic measurement, if necessary.
The objective is, in any case, an optimal (KSR) basic parametrization
of the respective weld with the following main properties:
• The welding result ranges above the minimum requirements.
• The resulting spot diameter is slightly larger than the nominal dia­
meter.
MainWeld (MainWLD)
Slope
2. %I (2.Heat) (amount of
current)
Special features of
8 mm tip-dress cutters
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• Dynamic resistance characteristic with the greatest possible res­
istance changes. Curves of this kind can be observed well and in­
dicate a stable process situation.
Information on the resistance curve and its visualization is
provided in Section 6 from page 25.
Welding quality cannot be assessed by interpreting the curve
characteristic but only by means of the spot diameter and possibly
by ultrasonic measurements! Controlling the curve characteristics
must be limited to assessment
• of the resistance characteristic: 
It should drop sharply at the beginning (contact) and, following
a temporary maximum, fall continuously towards the end of the
weld.
• of the voltage signal: 
It should be similar to the resistance characteristic.
• Expulsion-free schedule.
Also refer to Section 6.3 from page 31.
• Settings of a possibly necessary PreWLD and PstWLD are cor­
rect. With regard to PreWLD (preliminary impulse), also refer to
page 28.
12.If the current parameter configuration generates an optimal and
stable weld, generation of the related reference curve (refer to Sec­
tion 7.3 from page 41) is permitted.
Otherwise, first optimize the parameters and then move to step 10.
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7.3 Generating reference curves
To generate a reference curve, it is necessary to record the resistance
characteristic during one or several faultless welds.
The following options are available for this purpose:
• Defining the resistance characteristic as reference curve.
Manual selection of a program-specific resistance characteristic
which is then loaded into the controller as program-specific reference
curve.
For procedure, refer to Section 7.3.2 from page 43
• Recording by recorder.
Automatic recording of resistance characteristics with subsequent fil­
tering and mean value definition. The resulting program-specific
mean value curves can then be loaded into the controller as program-
specific reference curves.
For procedure, refer to Section 7.3.3 from page 45
The weld timer checks the validity of reference curves while loading
the reference curves into the controller. The criteria for validity are de­
scribed on page 81.
In addition to generating program-specific reference curves (as de­
scribed in Section 7.3.3 from page 45), the STC (Sheet Thickness
Combination) functionality can also be used to generate sheet-thick­
ness-related reference curves. Refer to Section 16 from page 125.
7.3.1 Requirements
� If you wish to use the „Gun resistance compensation“ functionality,
the function has to be activated. 
For information on activation, refer to Section 12.1 from page 100.
� Make sure that the optimal (KSR) basic parameters have already
been defined and programmed for the respective welds (refer to Sec­
tion 7.2 from page 34).
%I compensation should be set to 0%, if possible, in order to be able
to use all compensation features later in UI control mode.
� Make sure that the electrode tips have been dressed and worked in.
The tip wear condition should be between 15 and 100 welds.
� Make sure that the UI measurement is active for the respective welds
(„Programming“ topic, „PSQ“ tab, „UIR“ subtab: „Measurement (S)“
and „Measurement (P)“ parameters).
� Make sure that UI regulation and monitoring have been deactivated
for the respective welds.
� If the resistance characteristics are not generated on a component
but a sheet strip, the following applies:
• The resistance characteristic of the first spot on a sheet must not
be used to define or determine a reference curve.
• Leave a clearance of at least approx. 20 mm between the spot
welds.
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� Do not usewelds with expulsion to define a reference curve.
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7.3.2 Defining the resistance characteristic as reference curve
1. Observe the requirements referred to in Section 7.3.1 on page 41.
2. Choose which BOS window is best suited to define the reference
curve for your project.
• „Programming“ topic, „PSQ“ tab, „UIR reference“ subtab
Basic options:
• After selection of spot name (1a) or weld timer and program
number (1b), the corresponding last measured resistance
characteristic can be loaded into the display (2), saved as *.rui
file (3), or defined as new reference curve of the respective pro­
gram (4).
• A saved resistance characteristic can be loaded into the display
(5), saved under a different name as *.rui file (3), or defined as
new reference curve (4) of the currently selected program (1b).
1a
1b
2
3
4
5Current
Voltage
Resistance
The weld timer checks the validity of reference curves while loading
the reference curves into the controller. For validity criteria refer to
page 81.
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• „Diagnosis“ topic, „PSQ“ tab
Basic options:
• After selection of the relevant weld timer (1) and stopping the
window update (3), the last 64 measured resistance character­
istics are loaded into the display via scroll bar (2) and defined as
new reference curve of the corresponding program (7). 
Please note: The curve shown here is merely an example and
cannot be used as reference curve!
• A currently shown resistance characteristic can be examined
on the basis of the following functions:
• Display of the data (6) at the current position (4a, 4b) of the
selected cursor (4)
• Display of min., max. or mean value (5) between the two
cursor lines (4a, 4b).
1
3
2
7
4a
6
5
4
4b
3. If you use the BOS window in the „Diagnosis“ topic, „PSQ“ tab, (see
above), choose the „Program“ option in the „Filter“ area (3) and indic­
ate the program to be used for recording the data in the further
course.
4. Perform the test weld(s).
5. Check the weld quality by means of the spot diameter and ultrasonic
measurements, if necessary. In the further course, you should only
use resistance characteristics of faultless welds.
6. Load the corresponding resistance characteristic into the display and
define it as new reference curve.
The weld timer checks the validity of reference curves while loading
the reference curves into the controller. For validity criteria refer to
page 81.
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UI regulation can then be activated for the respective weld. For informa­
tion on this topic, refer to Section 7.4 from page 53.
7.3.3 Recording by recorder
1. Please note the requirements referred to in Section 7.3.1 on page 41.
2. Choose the „Settings“ topic, „UIR setup“ tab, „Recording mode“ com­
mand button (1).
The „UI setup“ application (2) is started.
After starting the „UI setup“ application, the command button text (1)
changes from „Recording mode“ to „Exit BOS_UI_Setup“.
The „UI setup“ application can only be closed again using this com­
mand button.
1
2
3 4 5 6 7
9
8
Fig.�11: “UI setup” window: Recording by recorder
3. Use the left checkbox (Fig. 11: Position 3) to determine the weld
timers for which the recorder function is to be activated.
4. Use the checkbox in the „New recording“ columns (Fig. 11: Position
7) to determine whether available recorded resistance characterist­
ics (Fig. 11: Position 4) are to be deleted before the recording of fur­
ther curves is started.
In the status area for recording (Fig. 11: position 8), the system shows
you the current program-related number of all available recordings
for the weld timer selected on the left (blue line).
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5. If needed, limit the recording to
- selectable programs (Fig. 11: Position 5)
- programs without active UI regulation (Fig. 11: Position 6).
6. Start recording using the „Start recording“ command button (Fig. 11:
Position 9).
In the status area for recording (Fig. 11: Position 8), you can observe
the recording progress.
After the start of recording, the command button text (Fig. 11: Posi­
tion 9) changes from „Start recording“ to „Stop recording“.
7. When the scope of recording meets your requirements, stop the cur­
rent recording using the „Stop recording“ command button (Fig. 11:
Position 9).
8. Close the „UI setup“ application.
To do this, bring the BOS window to the foreground again and select
the „Exit BOS_UI_Setup“ command button in the „Settings“ topic,
„UIR setup“ tab.
The „UI setup“ application is exited.
The system then shows you the curves recorded for a program as
“pencil of curves ” (see Fig. 12:).
9. Check the weld quality by means of the spot diameter and ultrasonic
measurements, if necessary. In the further course, you should only
use resistance characteristics of faultless welds.
10.Delete all curves which are not suitable to create the reference curve
and then define the mean value curve (reference curve).
� Delete the welds with expulsion. For detailed information on welds
with expulsion, refer to Section 6.3 from page 31.
� Delete the curves recorded immediately after dressing. These
curves stand out due to their low resistance.
� Delete curves of welds, if needed, where (too high) %I correction
was active. Please note that %I correction can be caused by active
%I stepping (stepper; only relevant for KSR mode) as well as by
parameter setting in the „Corrections“ topic, „Correction“ tab.
%I stepping and wear of selected (Fig. 12: Position 1) actual
curves are displayed by the system (Fig. 12: Position 5).
This work can be performed both manually and automatically:
• Manually:
Select the relevant program and the actual curve to be deleted
(red) (Fig. 12: Position 1) and activate the „Delete this curve“ com­
mand button (Fig. 12: Position 2).
Having deleted all the curves not needed, use the remaining
curves to create the mean value curve (Fig. 12: Position 3). The
mean value curve is displayed in red color. The black curves show
the minimal and maximal resistance characteristics.� The result is
shown in Fig. 13:
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1
2
3
5
4
6
Fig.�12: Deleting superfluous resistance characteristics
Fig.�13: Display of the mean value curve (reference curve)
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• Automatically:
Press the „Delete + avg. curves“ command button (Fig. 12: Posi­
tion 4). The „Delete + avg. curves “ window appears:
1 2
3
4
Fig.�14: „Delete and average curves“ window
Use the left checkboxes (Fig. 14: Position 1) to determine the weld
timers for which the automatic procedure is to be activated.
Limit the automatic procedure to selectable programs (Fig. 14: Po­
sition 2) and/or certain criteria (Fig. 14: Position 3).
Effect of activated checkboxes:
• „Expulsion“:
Deleting welds with detected expulsion.
• „Current correction factor“:
Deleting welds with %I corrections greater than the specified
limit value.
• „Count“:
Deleting welds with electrode wear exceeding the specified lim­
its.
• „Create avg. curve“:
Define the corresponding program-specific mean value curves
(reference curves) from the remaining curves.
Click on the „Continue“ command button to start the automatic
procedure. 
If „Create avg. curve“ is active, the reference curves generated are
saved in the standard path for UI setup (can be set using the con­
figuration tool) under the „Reference_Curves“directory sorted as
*.rui files according to weld timer designations.
The system saves information on deleted curves and generated
mean value curves in a log file which you can view using the „Detail
info“ command button (Fig. 14: Position 4).
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11.Transfer the mean value curve (reference curve) to the weld timer.
This action can also be performed manually or automatically.
NOTICE
Transfer of an unsuitable resistance characteristic
If an unsuitable resistance characteristic is declared as reference
curve, this may lead to frequent/major interference or even to un­
satisfactory welding results.
� Make sure before you start the transfer that a suitable curve has
been selected. A selected curve is displayed in red color.
� Never trigger the transfer without reason.
• Manually:
Select the relevant program (Fig. 15: Position 1) or the relevant
program and the required actual curve (Fig. 12: Position 1) and
press the „Reference schedule --> Timer“ (Fig. 15: Position 2)
command button.
1
2
3
Fig.�15: Transferring the mean value curve to the WT
� Please note the subsequent completion message.
The transferred curve can only be used as reference curve if de­
clared as „valid“ by the weld timer:
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The weld timer checks the validity of reference curves while load­
ing the reference curves into the controller. For validity criteria
refer to page 81.
When the transferred curve has been declared as valid, you may
activate the UI regulation for this weld.
How to activate the UI regulation is described in Section 7.4 from
page 53.
Programs with valid reference curves are easily recognized in the
„Overview“ topic using the „Curve valid“ option button. Refer to Sec­
tion 9.1.1 from page 81.
• Automatically:
Press the „Ref. curves (PC) -> SST“ command button (Fig. 15: Po­
sition 3 or Fig. 12: Position 6). The „Ref. curves (PC) -> SST“ ap­
pears:
1 2
3 4 5 6
Fig.�16: „Ref. curves (PC) -> SST“ window
Use the left checkboxes (Fig. 16: Position 1) to determine the WTs
for which the automatic procedure is to be activated.
Limit the automatic procedure to selectable programs (Fig. 16: Po­
sition 2), if necessary.
Press the „Ref. curves (PC) -> SST“ command button (Fig. 16: Po­
sition 5) to make a variety of settings for writing of the curves („Set­
tings for writing curves“ window is opened automatically) and then
start the automatic procedure.
If you want to open the „Settings for writing curves“ window only,
press the „Settings“ command button (Fig. 16: Position 3).
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1
2
3
Fig.�17: „Settings for writing curves“ window
Effect of activated checkboxes (Fig. 17: Area 1):
• „Special programs (excluded)“:
Transfer of mean value curves (reference curves) of certain
programs can be prevented here.
This is useful e.�g. for dressing and calibration programs.
• „Regulation on“:
If activated, the system switches on the program-specific UI
regulation („Programming“ topic, „PSQ“ tab, „UIR“ subtab,
„Regulation (P)“ parameter) after transfer of a valid reference
curve.
• „Monitoring on“:
If activated, the system switches on the UI specific monitoring
(„Programming“ topic, „PSQ“ tab, „UIR“ subtab „Monitoring (P)“
parameter) after transfer of a valid reference curve.
• „Reference values for UIR monitoring“:
If activated, the system determines reference values for the
program-specific UI monitoring from the mean value curve (ref­
erence curve) generated and also writes the values into the
weld timer after transfer of a valid reference curve.
The values are provided under the „Programming“ topic, „PSQ“
tab, „UIR monitoring“ subtab in the „Reference“ input fields.
• „Reference value UIP=100“:
If activated, the system writes the reference value „100“ for the
„UIR“ monitoring variable into the weld timer in case of pro­
grams where the reference curve is generated on the basis of
mean value calculation.
• „Tolerance“:
If activated, the system displays additional input options
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(Fig. 17: Area 2) for definition of tolerances and to switch the
respective UI monitoring variables on/off (Fig. 17: Position 3).
The settings made here are written into the weld timer as pro­
gram-specific UI monitoring data after transfer of a valid refer­
ence curve.
The values are provided under the „Programming“ topic, „PSQ“
tab, „UIR monitoring“ subtab in the corresponding input fields.
For detailed information on UI monitoring, please refer to Section 8
from page 63.
� Please note the completion message after transfer.
Transferred curves can only be used as reference curves if they
have been declared as „valid“ by the weld timer.
Whether that was the case is saved in a log file which you can view
using the „Detail info“ command button (Fig. 16: Position 4).
The criteria for validity of reference curves are described on
page 81.
When a transferred curve has been declared as valid, UI regula­
tion is possible for the respective weld and already activated auto­
matically depending on the „Regulation on“ checkbox (Fig. 17:
Area 1). 
How to activate UI regulation manually is described in Section 7.4
from page 53.
Programs with valid reference curves are easily recognized in the
„Overview“ topic using the „Curve valid“ option button. Refer to Sec­
tion 9.1.1 from page 81.
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7.4 Activating UI regulation
If a valid reference curve was generated for a program (refer to Sec­
tion 7.3 from page 41), activation of UI regulation is possible for this pro­
gram.
 
1. Select the „UIR“ subtab in the „Programming“ topic, „PSQ“ tab.
2. Choose the respective spot name (1a) or weld timer and program
number (1b).
3. Activate the UI regulation.
To do this, you must -�in addition to the existence of a valid reference
curve�- set the „Measurement (S)“, „Measurement (P)“, „Regulation
(S)“ and „Regulation (P)“ parameters to „On“ (2).
The programs working with active UI regulation are easily recogniz­
able in the „Overview“ topic using the „Regulation active“ option but­
ton. Refer to Section 9.1.1 from page 81.
Detailed information on the effects of the available parameters is
provided in the BOS online help.
The most important parameters are described in Section 7.4.1 from
page 54.
For information on the PSQ status display (3), refer to Section 9.1.2
page 82.
1a
3
1b
2 2
2 2
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7.4.1 Description of the most important UI parameters
Detailed information on the effects of the available parameters is also
provided in the BOS online help.
Measurement (�S)
OFF: the UI measurement logic is deactivated for all programs of the
weld timer - irrespective of the Measurement�(P) parameter.
ON: The UI measurement logic is activated for all programs of the weld
timer and can be switched on/off program-specifically using the Meas­
urement (P) parameter.
Expulsion current control
Determines in combination with Expulsion decay time and Detection of
expulsions how the controller reacts to a detected expulsion. The con­
troller changes the current at the time of expulsion by the programmed
percentage (+/- values are possible).
Measurement �(P)
OFF: the UI measurement logic is deactivated for the program dis­
played.
ON: the UI measurement logic is activated for the program displayed -
if it has been released via timer-globally Measurement (S). An active
measurement logic is the requirement for