Replacing heat pipes – Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) - ForGe Control User Manual
Page 95
Rockwell Automation Publication 7000-UM202B-EN-P - June 2014
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Component Definition and Maintenance
Chapter 3
Replacing Heat Pipes
For the largest power ratings of AFE rectifiers, heat pipes are used. Heat pipes
weigh approximately 13 kg (28 lb). To replace a heat pipe:
1.
Loosen heat pipe locking nuts on top of heat pipe horizontal fin support
(center nut at each sink).
On 6600V drives only:
Loosen heatsink nylon shipping bolts on bottom
white heatsink retaining bracket (
).
2.
Remove the load from the clamp head as described in
.
3.
Completely remove SGCT from the heat pipe that is being replaced as
described in
4.
Remove snubber resistor lugged connection at front of heatsink block and
the thermistor connection if present.
5.
Remove top heatsink horizontal fin support.
6.
Remove the front white heat pipe retaining bracket at bottom of heatsink
block.
7.
Pull heatsink forward, and lift up and out of powercage. Do not remove
clamp head glass rods.
On both the ends and middle heat pipes there will be resistance pulling the
heatsink forward due to the pin in the socket power connection is being
disconnected as the heat pipe is being pulled forward).
8.
Install the new heat pipe.
9.
Replace front white heat pipe retaining bracket.
10.
Replace top heatsink horizontal fin support.
11.
Replace the snubber resistor wire lugged connection and thermistor
connection, if present.
12.
Replace the SGCT as described in
.
13.
Re-apply clamp force to heat pipes:
a. Apply a thin layer of Electrical Joint Compound (Alcoa EJC No.2 or
approved equivalent) to the clamp head pressure pad face.
b. Tighten the clamp to the proper force until you can turn the indicating
washers by the fingers with some resistance.
ATTENTION: If present, remove plastic film from the heat sink before
installation. Failure to remove the film will result in device failure.