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Lance Electrical problem

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New Member
Jan 12, 2011
Reaction score
New to forum, need help.
alternator putting out zero (ammeter goes to zero, no movement from loads...batt voltage drops below 12...)
found no voltage on field terminal at alternator
found bad connector on voltage regulator end, replaced, now have 12V at field term alt
cranked engine to test, alternator immediatly began charging, 30Amps
ran for a few minutes while celebrating
then suddenly alternator cuts off (ammeter goes to zero, no movement from loads...batt voltage drops below 12....same old thing)
I cut ALT master on/off, no change, check breakers....same routine, will not come back on
cut off engine, check alt field term, still has voltage - oh no, a new problem?

crank engine again just to verify.....alt does not come on at all
cut alt switch off/on, no change,
just for heck of it, cut master off/on....alt springs to life....stays on.....
how can this be? voltage regulator and field wire feed from bus through alt switch...

now, with alt running, I try cutting off alt switch...and yes, it cuts off alternator as it should
I try cutting off master with alt switch on.....it cuts off alternator also (seems to me it should not have)

so what could it be?
alt switch feeds off bus bar through 5 amp circuit breaker....could master off/on be resetting circuit breaker?
or....resetting voltage regulator or overvoltage relay?

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