Siemens G120P

Service, maintenance and fault rectification
Fault rectification
8
89 |
98
Siemens
A5E36496664A_d
Building Technologies
2016-03-17
Rectifier tests
Positive measuring
point
Negative measuring
point
Expected result
OK
L1 DC- Diode block – OL/High impedance

L2 DC- Diode block – OL/High impedance

L3 DC- Diode block – OL/High impedance

DC + L1 Diode block – OL/High impedance

DC + L2 Diode block – OL/High impedance

DC + L3 Diode block – OL/High impedance

DC- L1 Diode aperture – typically 0.3 – 0.5V

DC- L2 Diode aperture – typically 0.3 – 0.5V

DC- L3 Diode aperture – typically 0.3 – 0.5V

IGBT bridge test
Positive measuring
point
Negative measuring
point
Expected result
OK
U DC + Diode aperture – typically 0.3...0.5 V

V DC + Diode aperture – typically 0.3...0.5 V

W DC + Diode aperture – typically 0.3...0.5 V

U DC- Diode block – OL/High impedance

V DC- Diode block – OL/High impedance

W DC- Diode block – OL/High impedance

How to proceed if a fault is discovered
 The variable speed drive has failed one of these tests:
 Remove the Power Module (power unit) in order to replace or repair it.
 A short circuit is present at the input rectifiers or at components of the IGBT
bridge:
 Check the state of fuses in the supply line, of contactors, disconnectors or of
the motor itself.
Remember that an apparently open circuit can also occur following a component
short-circuit and the resulting strong flow of current.