Piper CHEROKEE WARRIOR PA-28-151 1995 Maintenance Manual page 371

PIPER CHEROKEE WARRIOR SERV I C E M A N U A L
TABLE XI-I. TROUBLESHOOTING ELECTRICAL SYSTEM (cont.)
Trouble
Output indicated on ammeter
does not meet minimum values
specified in alternator system test
procedure. (cont.)
Field circuit breaker trips.
Revised: February 28, 1995
Cause
ALTERNATOR (cont.)
High resistance connections in
field or output circuit.
Open rectifier.
Short circuit in field circuit.
Short circuit in field winding of
alternator.
(Continued on next page)
2D12
Island Enterprises
Remedy
Check visually for loose binding
posts at the various junction
points in system: alternator, battery
post, lugs on ammeter, connections
at voltage regulator, circuit
b r e a k e r, etc. Examine crimped
terminal ends for signs of
d e t e r ioration at crimp or strands
of broken wire at crimp. Tighten
any loose binding posts. Replace
bad wire terminals.
Internally opening of any of the
six rectifiers will result in a
d e f inite limitation on the current
that can be drawn from the
a l t e rn a t o r. If no fault is found
after checking the previous causes
of low output, assume a faulty
r e ctifier exists. Have rectifier
replaced.
Disconnect field wiring at terminal
of alternator. Turn master switch
ON. If breaker continues to trip,
proceed to disconnect each leg of
field circuit, working from the
alternator towards the circuit
breaker, until breaker holds when
reset. Replace component or
wire which was isolated as
d e f e ctive.
Disconnect field wiring at termi-
nal of alternator. Turn master
switch ON. Reset breaker. If
breaker fails to trip again, the
short is in the alternator field
c i rcuit. Check brush holders for
shorting against frame. If there
are no signs of a physical short
circuit at field terminal or brush
holder, replace alternator.
ELECTRICAL SYSTEM