Yaskawa YASNAC PC NC Maintenance Manual - Manual (Page 68)

Chapter 4: Troubleshooting PC NC Maintenance Manual
4-47
AL-01:Overcurrent
Error Contents The output current flowed more than the overcurrent detection value
(rated current 150%) or the inverter output (load) was short-circuited.
Detection Methods An alarm will sound in the following cases. When either of maximum
value of output current (Iu, Iv, Iw) exceeds the overcurrent level, or
when the transistor (IGBT) between CE (between collector emitters) is
abnormal drive.
The three-phase current detected by the current detector is rectified in
the full wave. If this current value exceeds the overcurrent detection
drive level, the current is instantaneously intercepted, and the overcur-
rent detection signal is turned ON. Or, when transistor (IGBT) is not
normally turned ON despite the gate signal was turned OFF, the current
is instantaneously intercepted, and the overcurrent detection signal is
turned ON.
If the overcurrent detection signal has been turned ON, the drive is
stopped and the alarm is displayed.
Cause and measures
CPF01 Controlling circuit error
2
More than two seconds of transmission error has
occurred when inverter control card and operator
transmission are consistent once after power
turned ON. ---- S
• • Control card fault WDT time-out (LED display of I/O card two digits) ---- S
Cause Measures
Main circuit improper wiring Check wiring according to the interconnect chart.
Motor winding layer-short Check the resistance value between motor terminals.
Exchange the motor with a non-defective one.
Motor encoder fault Confirm that there is no abnormal motor speed changes by
speedometer indication or drive state display (U1-01).
Exchange encoder or motor.
Unit code (C1-56) improper setting Confirm the control parameter (C1-56) setting, and refer to the
setting list.
Motor code improper setting Confirm the control parameter (C1-25) setting, and refer to the
setting list.
Control parameter setting is defective. Refer to the setting list for the control parameters.
Control card fault Exchange unit (exchange control card)
Table 4.18: Alarm Descriptions (Continued)