Rockwell Automation LPM20 Liquid-Cooled AC Drive with High Performance Drive Control - Manual (Page 60)

3-6 Troubleshooting
Test Equipment Needed To
Troubleshoot An isolated multimeter will be needed to measure the DC bus voltage and to
make resistance checks. Note that dedicated troubleshooting test points are
not provided.
Verifying That DC Bus
Capacitors Are Discharged
The LPM20 drive’s DC bus capacitors retain hazardous voltages after input
power has been disconnected. Perform the following steps before touching
any internal components:
1. Turn off and lock out input power. Wait five minutes.
2. Verify that there is no voltage at the power module’s input power
terminals (L1, L2, and L3) as shown in Figure 1.8 .
3. Measure the DC bus potential with a voltmeter while standing on a
non-conductive surface and wearing insulated gloves (1000 V). The DC
bus measurement points are located on the Inverter (see
Figure 3.2 ).
4. After the drive has been serviced, reapply input power.
Figure 3.2 Location of DC Bus Voltage Measurement Points
!
ATTENTION: DC bus capacitors retain hazardous voltages
after input power has been disconnected. After disconnecting
input power, wait five (5) minutes for the DC bus capacitors to
discharge and then check the voltage with a voltmeter to ensure
the DC bus capacitors are discharged before touching any
internal components. Failure to observe this precaution could
result in severe bodily injury or loss of life.
Front View of Inverter Right Side View of Inverter
DC
Neg (-)
DC
Pos (+)
DC Bus Measurement
Points on Laminated
Bus Ass'y 0.25" x 0.032"
Male Faston. Accessible
by Removal of Top Cover.