Rockwell Automation Allen-Bradley IMPACT 1336 Series, Troubleshooting Manual, Page: 66 / 196

3–14 Access Procedures
Publication 1336 IMPACT-6.8 – November, 2002
Access Procedures
Removing the Motor Buses
The Motor Buses must be removed to access the Bus Capacitor Bank
and the Current Transducers (or “LEMs”).
Removal
!
ATTENTION: Wear a wrist-type grounding strap
when servicing 1336 IMPACT drives. Failure to
protect drive components against ESD may damage
drive components. Refer to Electrostatic Discharge
Precautions at the beginning of this chapter.
!
ATTENTION: Disconnect and lock out power from
the drive before disassembling the drive. Failure to
disconnect power may result in death or serious injury.
Verify zero bus voltage by measuring the voltage
between the Negative Capacitor Bus and both ends of
all three bus fuses. An open fuse does not show voltage
across both ends of the fuse. Failure to measure voltage
at both ends of the fuses may result in death or serious
injury. Refer to Figure 3.5. Do not attempt to service the
drive until the bus voltage has discharged to zero volts.
Important: Before you remove connections and wires from the
drive components, mark the connections and wires to
correspond with their component connections and
terminals to prevent incorrect wiring during assembly.
1. Perform the following procedures found earlier in this chapter:
•
Opening the Drive Enclosure
•
Removing the Control Board Mounting Plate
•
Removing the Precharge Board Mounting Frame
2. Remove the HV Guard that spans the bottom of the Inverter
Bay (held in place with hook-and-loop strips).
Referring to Figure 3.9 and the following steps, loosen the Current
Transducers:
1. Remove the two screws fastening the Top Cover on both
Current Transducers.
2. Slide the Top Covers back out of the way.
3. Remove the Front Cover and Clear Insulator.
4. Remove the harness connected to each Current Transducer.