Applicable Systems
GTM
Symptoms
The Picanol GTM weaving machine displays fault code 122: ERROR IN SK LOGIC (slow-motion logic error). The machine controller has detected an inconsistency in the slow-motion (SK) control logic during slow-speed operation. The loom stops and displays the fault, preventing further operation until the logic error is investigated and cleared.
Possible Causes
- Slow-motion control logic software error or parameter corruption causing inconsistent state transitions
- Proximity switch PXSM (slow-motion proximity sensor) signal intermittent or misaligned, providing unreliable input to the slow-motion logic
- Slow-motion clutch or brake actuator not responding correctly to controller commands, causing a mismatch between commanded and actual state
- PWRG power supply board instability affecting the slow-motion control circuit voltage levels
- Electrical noise or interference on the slow-motion control signal lines causing the logic to misinterpret actuator status
Troubleshooting Steps
- Step 1: Retry the slow-motion operation by pressing the slow-motion button again to determine if the error is transient
If the error clears and does not recur, it may have been a transient glitch; if it recurs, proceed to further diagnostics - Step 2: Check the slow-motion proximity switch PXSM position and signal output
The PXSM switch should be properly aligned per the GTM manual and should produce a clean on/off signal as the loom rotates; adjust or replace if signal is erratic - Step 3: Inspect the slow-motion clutch and brake actuator wiring and connections for damage or looseness
All connections should be tight with no corrosion; wiring should be intact with no chafing or insulation damage - Step 4: Verify the PWRG board output voltages to the slow-motion control circuit are within specification
Voltages should match the values in the GTM electrical manual; instability or low voltage indicates a PWRG board issue - Step 5: If all hardware checks are normal, reload the machine control parameters to factory defaults to eliminate parameter corruption as a cause
Parameters should reload without error and the slow-motion test should pass cleanly
How to Reset
To reset: 1) Press the slow-motion button to retry the operation. 2) If the error clears, the fault was transient. 3) If the error recurs, perform the diagnostic steps above. 4) After resolving the cause, clear the fault on the operator panel. 5) Run a slow-motion test cycle to confirm normal operation before resuming production.
Frequently Asked Questions
- Q: What is the slow-motion (SK) function on a Picanol GTM loom?
The slow-motion (SK) function allows the operator to rotate the loom at very low speed for setup, maintenance, and troubleshooting. It uses a dedicated slow-motion clutch and proximity switch (PXSM) to control the shaft position precisely. Fault 122 indicates the control logic detected an inconsistency in this system.
- Q: Is fault 122 a safety concern?
Fault 122 is classified as a Minor fault. It typically does not indicate a safety hazard but rather a control logic or sensor issue. However, if the slow-motion system is not functioning correctly, maintenance and setup operations may be affected. Always resolve this fault before performing manual setup work on the loom.
Source: Picanol GTM Machine Messages and Fault Codes Manual
Category: Textile