NOTE: This portion of the documentation covers the fault diagnostics of the WT6000 Weld Control. This section of the manual is geared towards line builders, maintenance personnel and welding engineers to assist with procedures related to programming the weld control.

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Chapter 10: Fault Diagnostics

In this section:


Complete Fault Diagnostics List


The following is a complete fault diagnostic list for the WT6000 Weld Control with timer software G08300. Under each fault name is a description and recommended corrective action. To view the description and corrective action, click on the fault name and the table will expand. Click on the name again to collapse the table.

FAULT NAME
INVALID SEQUENCE SELECTED
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the Weld Initiate bit goes HIGH and a schedule (sequence) number is selected via the Binary Select bits, which is beyond the range of available schedules.
Corrective Action
Ensure the schedule (sequence) number selected via the Binary Select bits is not beyond the range of available schedules. For example, if there are 99 schedules available, selecting schedule 100 or higher via the Binary Select bits will generate an INVALID SEQUENCE SELECTED FAULT, when the Weld Initiate bit goes HIGH.
WELD INITIATE NOT PRESENT
Options:
(FAULT) (ALERT)
Default:
(ALERT)
1
Occurs when function #61 (ABORT IF NO INITIATE FOR nn CYCLES) is used in the weld schedule and the Weld Initiate bit goes LOW within the amount of time programmed in the function.
2
Occurs when the Weld Initiate bit goes LOW before function #63 (TURN ON WELD COMPLETE) is executed in the weld schedule.
Corrective Action 1

Ensure the master controller (i.e. robot, PLC, etc.) is maintaining the Weld Initiate bit HIGH during the time function #61 is monitoring the bit.

Corrective Action 2

Ensure the master controller (i.e. robot, PLC, etc.) is maintaining the Weld Initiate bit HIGH until function #63 is executed in the weld schedule.

CONTROL STOP
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the Control Stop bit goes LOW anytime during the execution of the weld schedule. This bit is normally maintained HIGH.
Corrective Action
 
STEPPER APPROACHING MAX
Options:
(FAULT) (ALERT)
Default:
(ALERT)
1
Occurs at the 1st weld of step 5 in the stepper program. Indicates the final step in the stepper program has begun and the End of Stepper is approaching.
END OF STEPPER
Options:
(FAULT) (ALERT)
Default:
(FAULT)
1

Occurs at the last weld of step 5 in the stepper program.

Corrective Action
Reset the stepper program and replace the weld caps on the gun.
HIGH CURRENT LIMIT FAULT
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the weld processor detects that the current passed during the weld schedule exceeded the value programmed into the HIGH CURRENT LIMIT WINDOW % in the Setup Parameters.
2
Occurs when the weld processor detects that the current passed during the weld schedule exceeded the HI value programmed into function #76 (SEC. CURR LIMITS: HI = nnnn0 LOW = nnnn0) in the weld schedule.
Corrective Action 1
Ensure the percentage value programmed into HIGH CURRENT LIMIT WINDOW % in the Setup Parameters is correct for the welding application.
Corrective Action 2
Ensure the HI value programmed into function #76 (SEC. CURR LIMITS: HI = nnnn0 LOW = nnnn0) in the weld schedule is correct for the welding application.
Corrective Action 3
Ensure the value programmed into TRANSFORMER TURNS RATIO in the Setup Parameters is correct for the welding application.
Corrective Action 4
 
Corrective Action 5
 
LOW CURRENT LIMIT FAULT
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the weld processor detects that the current passed during the weld schedule was less than the value programmed into the LOW CURRENT LIMIT WINDOW % in the Setup Parameters.
2
Occurs when the weld processor detects that the current passed during the weld schedule was less than the LOW value programmed into function #76 (SEC. CURR LIMITS: HI = nnnn0 LOW = nnnn0) in the weld schedule.
Corrective Action 1
Ensure the percentage value programmed into LOW CURRENT LIMIT WINDOW % in the Setup Parameters is correct for the welding application.
Corrective Action 2
Ensure the LOW value programmed into function #76 (SEC. CURR LIMITS: HI = nnnn0 LOW = nnnn0) in the weld schedule is correct for the welding application.
Corrective Action 3
Ensure the value programmed into TRANSFORMER TURNS RATIO in the Setup Parameters is correct for the welding application.
Corrective Action 4
 
Corrective Action 5
 
EXTENDED WELD
Options:
(FAULT) (ALERT)
Default:
(FAULT)
1

Occurs when either function #94 (EXTEND WELD IF LOW CURRENT LIMIT FAULT) or #95 (EXTEND WELD IF CURRENT LESS THAN nnnn0) is used in the weld schedule and the condition is true.

If the extend weld (re-weld) is successful, an EXTENDED WELD (ALERT) will occur and the Weld Complete bit will go HIGH. If the extend weld (re-weld) is unsuccessful, both an EXTENDED WELD ALERT and a LOW CURRENT LIMIT FAULT will occur and the Weld Complete bit will stay LOW.

NOTE: This fault must be set to (ALERT) for the Weld Complete bit to go HIGH after a successful extend weld (re-weld). Otherwise, if set to (FAULT), the Weld Complete bit will stay LOW.

Corrective Action
See corrective action for LOW CURRENT LIMIT FAULT. Also, Ensure the value programmed into function #95 is correct for the welding application.
ISO CNTR OFF WHEN NEEDED
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the isolation contactor is not energized when required by the weld schedule.
Corrective Action
Ensure function #88 (TURN ON ISOLATION CONTACTOR) is in the weld schedule and inserted before the squeeze function.
ISO CNTR ERR-BRKR TRIPPED
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the weld processor detects the isolation contactor is energized (closed) when it should be de-energized (open). When this fault occurs, the weld processor activates the shunt-trip mechanism on the circuit breaker.
Corrective Action 1
Replace isolation contactor if the contacts are frozen shut.
Corrective Action 2
Replace isolation contactor auxiliary contacts.
HIGH C-FACTOR LIMIT
Options:
(FAULT) (ALERT)
Default:
(ALERT)
1

Occurs when function #92 (C-FACTOR LIMIT: HI=nnnn LO=nnnn) is used in the weld schedule and the C-Factor value calculated by the weld processor exceeds the high limit value programmed in the function.

Corrective Action 1
Ensure the "HI" value programmed into function #92 is correct for the welding application.
Corrective Action 2
High C-Factor Limit usually indicates current shunting is occuring in the secondary circuit. This can be cuased by current shunting paths. See Ch. 9: Advanced Topics for more information.
LOW C-FACTOR LIMIT
Options:
(FAULT) (ALERT)
Default:
(ALERT)
1
Occurs when function #92 (C-FACTOR LIMIT: HI=nnnn LO=nnnn) is used in the weld schedule and the C-Factor value calculated by the weld processor is less than the low limit value programmed in the function.
Corrective Action 1
Ensure the "LO" value programmed into function #92 is correct for the welding application.
Corrective Action 2
Low C-Factor Limit usually indicates an increase in the resistance of the secondary circuit. This can be caused by fraying welding cables. See Ch. 9: Advanced Topics for more information.
SYSTEM COOLING
Options:
Non-Programmable
Default:
(FAULT)
1

Occurs when the System Cooling bit goes LOW anytime during the execution of the weld schedule. This bit is normally maintained HIGH.

This bit can be used to set a weld processor fault when a system cooling problem exists somewhere in the welding process. For example, it could be used to indicate a transformer overtemp condition.

Corrective Action 1
Identify and correct any water flow issues.
WELD PROCEED
Options:
(FAULT) (ALERT)
Default:
(FAULT)
1
Occurs when function #70 (WAIT FOR WELD PROCEED) is used in the weld schedule and the Weld Initiate bit goes LOW before the Weld Proceed bit goes HIGH.
2
Occurs when function #67 [WAIT FOR INPUT #n TO BE n (0 = OFF 1 = ON)] is used in the weld schedule and the Weld Initiate input bit goes LOW before the specified input bit goes either OFF or ON.
3
Occurs when function #66 [WAIT nnn CY INP #n TO BE n (0 = OFF 1 = ON)] is used in the weld schedule and the specified input bit does not go either OFF or ON within the number of cycles specified.
Corrective Action
 
PRESSURE SWITCH
Options:
(FAULT) (ALERT)
Default:
(ALERT)
1
Occurs when function #69 (WAIT FOR PRESSURE SWITCH INPUT) is used in the weld schedule and the Weld Initiate bit goes LOW before the Pressure Switch bit goes HIGH.
2
Occurs when function #68 (WAIT nn CY FOR PRESSURE SWITCH INPUT) is used in the weld schedule and the Pressure Switch bit does not go HIGH within the amount of time programmed in the function.
Corrective Action
 
PRESSURE NOT ACHIEVED
Options:
(FAULT) (ALERT)
Default:
(FAULT)
1
Occurs when function #74 (WAIT nnn MS FOR PRESSURE ACHIEVED) is used in the weld schedule and the programmed pressure is not achieved within the amount ot fime programmed in the function.
Corrective Action 1
Check analog feedback circuit for problems.
Corrective Action 2
Check for mechanical problems with the weld gun related to air pressure, e.g. water in air lines, pressure regulator set too low, etc.
IO
Options:
Non-Programmable
Default:
(FAULT)
1

Occurs when an EtherNet/IP network communication timout occurs. Once EtherNet/IP communication is re-established, the fault will automatically reset.

2

Occurs when the weld processor looses communication with any device connected to the SSPI port:

  • CIOM (Contactor I/O Module
  • AIOM (Analog I/O Module
  • DIOM (Discrete I/O Module)
  • GFM (Ground Fault Module)
  • MCCM (Multi-Contactor Control Module)
Corrective Action
 
CONTROL IN NO WELD
Options:
(FAULT) (ALERT)
Default:
(ALERT)
1

Occurs when a weld schedule is initiation while the weld processor is in No Weld Mode (i.e. the Weld / No Weld bit is LOW).

Corrective Action
 
INITIATION ON POWER-UP
Options:
Non-Programmable
Default:
(FAULT)
1

Occurs when the weld cabinet is powered-up (i.e. circuit breaker is switched ON) and the weld processor detects that both the Weld Initiate bit is HIGH and one or more Binary Select bit is HIGH. In this condition, a weld schedule WILL NOT initiate.

Corrective Action
Remove Weld Initiate bit, clear faults and re-initiate the weld schedule.
RETRACT PILOT
Options:
(FAULT) (ALERT)
Default:
(FAULT)
1
Occurs when function #86 (VERIFY CYLINDER #n IS OUT OF RETRACT) is used in the weld schedule and the specified retract cylinder was in retraction when checked by the weld processor.
Corrective Action
 
CONTROL TRANSFORMER VOLTAGE
Options:
Non-Programmable
Default:
(FAULT)
1

Occurs at power-up only, when an under or over voltage condition exists on the 24VAC secondary tap of the control transformer. The CIOM-TB module monitors the 24VAC secondary tap of the control transformer for either an under or over voltage condition. This ensures the primary of the control transformer is tapped properly for the incoming line voltage.

NOTE: This fault is not used on the WT6000 in the Mini-Pak enclosure configuation.

Corrective Action
 
WELD INTERRUPTION
Options:
(FAULT) (ALERT)
Default:
(FAULT)
1
Occurs when the Weld / No Weld bit goes LOW while the weld control is passing current during the execution of a weld schedule.
2
Occurs when the circuit breaker on the weld cabinet is switched OFF while the weld control is passing current during the execution of a weld schedule. The fault will appear after the circuit breaker is switched back ON and the weld processor re-initializes.
3
Occurs when the weld current is interrupted during the weld time.
Corrective Action 1
 
Corrective Action 2
 
Corrective Action 3
Ensure weld gun is not opening early. Check for intermittent open connection in the weld tooling (primary or secondary).
LOW LINE VOLTAGE
Options:
(FAULT) (ALERT)
Default:
(FAULT)
1

Occurs when the AC line voltage drops below a point where the DC power supply on the CIOM-TB module can no longer regulate the +24VDC it supplies to the devices downstream. This fault is monitored continuously.

NOTE: This fault is not used on the WT6000 in the Mini-Pak enclosure configuation.

Corrective Action
 
IGBT SATURATION
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the weld processor detects an instantaneous over-current event, which exceeds the design rating of the IGBT modules within the inverter assembly.
Corrective Action
Replace inverter assembly.
IGBT POWER SUPPLY
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the IGBT Gate Board within the inverter assembly has failed. This fault is monitored continuously.
Corrective Action
Replace inverter assembly.
AC LINE PHASE
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the weld processor detects a line phase is either incorrect or missing. This fault is monitored continuously.
Corrective Action
Correct power problem or replace / install missing phase.
BUS VOLTAGE
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the weld processor has detected the DC bus within the inverter assembly did not charge to the correct level. This fault is monitored continuously.
Corrective Action
Reset circuit breaker on weld control cabinet. Replace inverter assembly if continually re-occurs.
BUS CHARGING
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the weld processor has detected the DC bus within the inverter assembly did not charge correctly (either too slow or too quickly). This fault is monitored continuously.
Corrective Action
Reset circuit breaker on weld control cabinet. Replace inverter assembly if continually re-occurs.
SECONDARY DIODE
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the weld processor has detected a shorted secondary diode within the welding transformer.
Corrective Action
Replace welding transformer.
SECONDARY CURRENT SENSOR
Options:
Non-Programmable
Default:
(FAULT)
1

Occurs at the initiation of a weld schedule, when the weld processor does not detect a proper connection to the secondary current monitoring coil when it should.

This fault will only occur when the weld processor is configured to either the (PRI/SEC) or (SEC/SEC) Firing Monitoring Mode in the Setup Parameters.

Corrective Action
The secondary current coil is either improperly connected to the weld processor or it is bad. If proper connection has been verified and the fault still persists, replace the coil with a known good one.
GROUND
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when a current imbalance exists between the two output terminals of the inverter assembly.
Corrective Action
Identify and correct unidirectional current path to ground between the output of the inverter assembly and the primary of the welding transformer.
TEMPERATURE
Options:
Non-Programmable
Default:
(FAULT)
1
Occurs when the weld processor has detected the temperature of the inverter cooling manifold (chill plate) had exceeded safe operating limits.
Corrective Action 1
Water Cooled Inverter: Ensure the cooling water inlet temperature is < 95° F (35° C). See Cooling Requirements in Ch. 1: System Overview.
Corrective Action 2
Air Cooled Inverter: Ensure the ambient air temperature around the weld cabinet does not exceed 104° F (40° C). See Cooling Requirements in Ch. 1: System Overview.
SOFT OVERCURRENT
Options:
(FAULT) (ALERT)
Default:
(ALERT)
1
Occurs when the impedance of the secondary circuit creates a current draw that causes the inverter to reach or exceed its maximum output current rating.
2

Occurs when the target secondary current programmed into the weld schedule causes the inverter to reach its maximum output current rating.

To determine the maximum target secondary current, multiply the inverter maximum output current rating by the transformer turns ratio. For example, 400A inverter x 50:1 turns ratio = 20,000A max target secondary current. Thus, programming more than 20,000A into the weld schedule may cause a SOFT OVERCURRENT FAULT.

Corrective Action
 
CURRENT REGULATION
Options:
(FAULT) (ALERT) (NONE)
Default:
(ALERT)
1
Occurs when the inverter reaches its maximum IGBT on-time rating before the target secondary current is achieved. Thus, whatever current level is achieved at max IGBT on-time, is what will be delivered to the welding transformer.
Corrective Action
 
HIGH / NO MOTOR CURRENT
Options:
(FAULT) (ALERT) (NONE)
Default:
(FAULT)
1
Occurs when function #16 (MOTOR CURR LIMITS HI=nnnn ma LO=nnnn ma) is used in the weld schedule and the measured tip dress motor current is above the HIGH limit any time during the 8ms checking period. When this fault occurs, the motor is immediately turned off.
2
Occurs when the measured tip dress motor current is <= 20ma any time during the 8ms checking period. When this fault occurs, the motor is immediately turned off.
Corrective Action
 
TIP DRESS
Options:
(FAULT) (ALERT) (NONE)
Default:
(FAULT)
1
Occurs when function #16 (MOTOR CURR LIMITS HI=nnnn ma LO=nnnn ma) is used in the weld schedule and the measured tip dress motor current is above the value programmed into the LOW limit for less than (1) second of accumulated time. This fault will not occur if the measured current remains above the LOW limit for (1) or more seconds of accumulated time.
Corrective Action
 

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