TM9-4120-400-14
4-39.
RECTIFIER CR1 AND CAPACITORS (C1 and C2 for 3 phase units) or (C1 and C6 for
single phase units). - continued
TESTING
Rectifier CR1.
Tag and disconnect wire leads.
a.
b.
Using a multimeter on high ohms setting connect negative (-) lead to terminal 2 and positive (+) lead to
terminal 1 or 3. A low resistance reading should be obtained.
Connect positive lead to terminal 2 and negative lead to terminal 1 or 3. A very high resistance or open
c.
circuit reading should be obtained.
Connect positive lead to terminal 4 and negative lead to terminal 1 or 3. A low resistance reading should
d.
be obtained.
Connect negative lead to terminal 4 and positive lead to terminal 1 or 3. A very high resistance or open
e.
circuit reading should be obtained.
f.
Replace defective rectifier and capacitors C1 and (C2 for 3 phase units) or (C6 for single phase units).
See wiring diagram figure 4-4 and tags and connect the wire leads. Remove tags.
g.
REPLACEMENT
1. Tag and disconnect wire leads.
Remove screw (1) and pull rectifier (2) from unit.
2.
Cut terminals from wire leads and capacitors C1 and (C2 for 3 phase units) or (C6 for single phase units).
3.
Remove capacitors (3 and 4).
4.
NOTE
When rectifier CR1 is replaced capacitors C1 and (C2 for 3 phase units) or (C6 for single
phase units) should also be replaced.
See wiring diagram figure 4-4 and tags and attach capacitors (3 and 4) and wire leads to terminals.
5.
See the wiring diagram figure 4-4 and tags and connect the terminals to rectifier (2). Remove tags.
6.
Install rectifier (2) using screw (1).
7.
NOTE
FOLLOW-ON MAINTENANCE:
Install junction box (para 4-27).
Install top front panel (para4-11).
4-96