UL4
Undertorque Detection 2
Yaskawa · J1000 AC Drive
What does UL4 mean?
The motor current has fallen below a secondary minimum value set in L6-05 for longer than the allowable time specified in L6-06. Similar to UL3, this suggests either incorrect parameter tuning for the current load or a fault in the machine's mechanical system that is causing reduced torque.
Source: Yaskawa J1000 AC Drive
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