Siemens G120P Manual page 54

Fault rectification
6
Hardware diagnostics
Check/Test
Switch off the power supply
Securing
Ensure that there is no voltage present at
the drive.
Damage caused by external factors
Electrical damage
Interference by customers
Fuses
Rectifier tests
Positive measuring Negative measuring point Expected result
point
L1 DC+
L2 DC+
L3 DC+
L1 DC
L2 DC
L3 DC
DC+ L1
DC+ L2
DC+ L3
DC L1
DC L2
DC L3
54
Siemens AG
Preliminary tests
Description
Ensure that the drive is disconnected from the line supply.

 Secure the drive so that it cannot be switched on again.
Measure the voltage between L1/L2 and L3.

 Make sure that the system is completely de-energized.
Check whether parts are damaged, for example by corrosion, paint,

moisture, oil, dust, powder etc.
Look for evidence of flashovers or burning at the power terminals.

These are caused by connecting the power cables incorrectly.
Examine the drive for signs that customers have attempted to repair

the drive themselves.
 Check the sizes of the fuses.
 Make sure that they are not "open".
Static check on the drive
The following checks are standard tests. These tests can be performed on most
drives which are designed in accordance with the conventional principle "Rectifier –
DC bus – IGBT bridge". The customer is not meant to use the DC bus terminals on
the PM230/G120P. However, the terminals are accessible on some models.
Set the multimeter to "Diode" in order to measure the terminals.
The following tables show where to connect the test cable on the drive and what
test result you are likely to receive.
Diode aperture – typically 0.3 – 0.5V
Diode aperture – typically 0.3 – 0.5V
Diode aperture – typically 0.3 – 0.5V
Diode block – OL/High impedance
Diode block – OL/High impedance
Diode block – OL/High impedance
Diode block – OL/High impedance
Diode block – OL/High impedance
Diode block – OL/High impedance
Diode aperture – typically 0.3...0.5 V
Diode aperture – typically 0.3...0.5 V
Diode aperture – typically 0.3...0.5 V
OK
OK
CM2G5111en
2014-05-16