ARMY TM 9-6115-643-24
AIR FORCE TO 35C2-3-445-22
TABLE 4-3. Generator Resistance Values At 25°C (77°F)
Component
Resistance
MEP-804A
MEP-814A
Exciter Stator
Between 28.657 & 38.771 ohms
Between 25.0335 & 33.8715 ohms
Exciter Rotor
Between 0.709 & 0.959 ohms
Between 0.2025 & 0.2739 ohms
Generator Rotor
Between 1.247 & 2.073 ohms
Between 1.2688 & 1.7166 ohms
Generator Stator
Between 0.146 & 0.198 ohms
Between 0.0717 & 0.0971 ohms
N O T E
Ambient temperature must be expressed in °C.
To convert °F to °C use: °F = °C x 9 + 5 +32
(1) To determine the resistance values at current ambient temperature, use the following formula:
R1 = RZ5 [1 + 0.00385 (T-25)]
Where:
R1 =
Unknown resistance
R25 =
Known resistance at 25°C (77°F)
T
=
Current ambient temperature
(2) Example for exciter stator leads at 5°C (41 °F) (MEP-804A):
R1 =
33.714
[1 + 0.00385 (5-25)]
R1 =
33.714
[1 + 0.00385 (-20)]
R1 =
33.714
[1 + -0.077)]
R1 =
33.714
[0.923]
R1 =
31.118
± 15% ohms
f. Using bearing puller, remove rectifier hub (12, FIGURE 4-10) from rotor assembly (23) shaft.
g. Pull two main rotor leads out of holes in exciter rotor (15).
h. Attach hub puller to two lead holes and remove exciter rotor (15) from rotor assembly (23) shaft.
i.
Remove key (16) from rotor assembly (23) shaft.
4.21.3 Installation.
a.
b.
c .
d.
4-40
Install key (16, FIGURE 4-10) on main rotor assembly (23) shaft.
Press exciter rotor (15) onto shaft, over key (16) and against shoulder of rotor assembly (23) shaft.
W A R N I NG
Use protective gloves when handling heated rectifier hub (12) to pre-
vent personal injury.
Heat rectifier hub (12) until it slides into place on rotor assembly (23) shaft with slight pressure.
Once rectifier hub (12) has cooled, pull two main rotor leads through holes in exciter rotor (15) and position for
attachment to rotating rectifier (10).
