ARMY TM 9-6115-641-24
AIR FORCE TO 35 C2-3-456-12
4-1o-3.
g.
h.
i.
j.
k.
i.
m.
n.
o.
p.
q.
r.
Testing Rotating Rectifiers. - Continued.
Connect negative lead of multimeter to F1 + stud and positive lead to CR1. Record resistance value.
Repeat steps f and g for CR2 and CR3.
Resistanc readings should be high in step f and low in step g. If any reading is high or low in both steps, rectifier
assembly is defective and must be replaced.
Connect all leads to F1 + assembly and tighten nuts to 24 in–lbs (2.7 Nm). Remove tags.
Tag and disconnect four leads from F2– assembly.
Connect negative lead of multimeter to F2- stud and positive lead to CR4. Record resistance value.
Connect positive lead of multimeter to F2– stud and negative lead to CR4. Record resistance value.
Repeat step 1 and m for CR5 and CR6.
Resistance readings should be low in step I and high in step m. If any reading is high or low in both tests, rectifier
assembly is defective and must be replaced.
Reconnect all leads to F2– assembly and tighten nuts to 24 in–lbs (2.7 Nm). Remove tags.
Install end bell cover on generator, paragraph 4–11-4, step n (MEP-802A) or paragraph 4–12–5, step g
(MEP-812A).
Connect negative battery cable and close access doors.
CR2
ETER
Figure 4-17. Testing Rotating Rectifiers
4-10-4. Testing Brushless Exciter Stator. Using multimeter, set for ohms, test the brushless exciter stator (Figure 4-18)
for open or shorted windings and grounds as follows:
NOTE
a.
b.
c.
d.
e.
f.
9.
Tests are performed with component installed.
Shut down generator set. Allow generator to cool to ambient temperature,
Open left side engine access door and disconnect negative battery cable.
Open storage box and output terminal board access doors.
Remove end bell cover from generator, paragraph 4-1 1–1, step e (M EP–802A) or paragraph 4-1 2–2, step h
(MEP-812A).
Disconnect F1 + and F2– exciter stator leads from terminal block (13, Figure 4–24) or (35, Figure 4-25) in gen-
erator end bell. Set multimeter for ohms and connect between disconnected leads, The resistance between
leads should be as shown in Table 4-1.
Readings other than shown in Table 4–1 indicates open or shorted windings and exciter stator must be re-
placed.
Connect multimeter between each exciter stator field lead and exciter stator lamination. Multimeter reading of
less than infinity indicates defective ground insulation and exciter stator must be replaced.
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