Lenze 9228E - Manual (Page 81)

79

3. Checking the power stage
The measurements described below are to be carried out only by
skilled specialists. Use a digital voltmeter. The measuring values
indicate the nominal value. If they are different from your measure-
ments, there is a defect.
3.1. Checking the mains rectifier
•
Disconnect the controller from the mains.
Caution!
Wait 5 minutes until the DC-bus is discharged no load!
•
Measure directly at the power terminals.
Measurement Measuring point Measuring value
Diodes in forward
direction L1
→
+UG
L2
→
+UG
L3 → +UG
-UG
→
L1
-UG
→
L2
-UG
→
L3
≈
0.4V
≈
0.4V
≈ 0.4V
≈
0.4V
≈
0.4V
≈
0.4V
Diodes in reverse
direction +UG
→
L1
+UG → L2
+UG
→
L3
L1
→
-UG
L2
→
-UG
L3
→
-UG
high resistance (OL)
high resistance (OL)
high resistance (OL)
high resistance (OL)
high resistance (OL)
high resistance (OL)
3.2. Checking the output stage
•
Disconnect the controller from the mains.
Caution!
Wait 5 minutes until the DC-bus is discharged!
•
Measure directly at the power terminals.
Measurement Measuring point Measuring value
Inverter diode in forward
direction U → +UG
V
→
+UG
W
→
+UG
≈ 0.4V
≈
0.4V
≈
0.4V
Inverter diode in reverse
direction UG
→
U
UG
→
V
UG → W
high resistance
high resistance
high resistance
Inverter diode in forward
direction -UG
→
U
-UG
→
V
-UG
→
W
≈
0.4V
≈
0.4V
≈
0.4V
Inverter diode in reverse
direction U
→
-UG
V
→
-UG
W → -UG
high resistance
high resistance
high resistance