Piper SEMINOLE PA-44-180, Maintenance Manual

Page: 209 / 881

CHART 2401. TROUBLESHOOTING (ALTERNATOR)
Trouble Cause Remedy
ALTERNATOR (cont)
Field circuit breaker trips. Short circuit in field winding Disconnect field wiring at
(cont) of alternator. terminal of alternator. Turn
on master switch. Reset
breaker and if breaker fails
to retrip, this isolates short
circuit to field of alternator it
self. Check brush holders for
shorting against frame. If
there are no obvious signs of
a physical short circuit at
field terminal or brush holder,
replace alternator. (Note:
Intermittent short circuit.)
Internal short circuiting of
the field can occur at various
positions of the rotor, there-fore,
reconnect field, reset breaker.
—CAUTION—
TURN MAGNETO SWITCH TO
OFF BEFORE TURNING
PROPELLER.
Pull propeller slowly by
hand turning alternator rotor
through 360° of travel.
Observe circuit breaker for signs
of tripping.
Output circuit defective. Short circuit in output circuit. Disconnect wiring at battery
post of alternator. Turn on
master switch. Disconnect
each leg of output circuit,
working from the alternator
towards the bus bar. Replace
component or wire which was
was isolated as defective. (See
schematic.)
- Battery installed with reversed Remove battery and reinstall
polarity. with correct polarity.
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
2 4 - 0 2 - 0 0
Page 24-05
Revised: May 15, 1989
1I17
PIPER AIRCRAFT