DETROIT DIESEL 53
7.1 Battery-Charging Generator
Fig. 4-20. DN Type 250 AC Self-Rectifying Generator (Alternator)
connected correctly (negative to negative and positive
Accidentally reversing the battery connections must he
to positive).
avoided.
Never use a fast charger with the battery connected or
Never disconnect the battery while an alternator is in
as a booster for battery output.
operation. Disconnecting the battery may result in
damage to the generator diodes due to the momentary
Never attempt to polarize the alternator
high voltage and current generated by the rapid
collapse of the magnetic field surrounding field
windings.
The alternator diodes are also sensitive to heat and
care must be exercise to prevent damaged to them
from soldering irons, ect.
If faulty operation of an alternator occurs on an
engine equipped with an insulated starting motor.
Check to be sure that a ground strap is presented and is
correctly insulated.
If a booster battery is to he used, the batteries must he
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