Electrical System - Westerbeke 35B THREE Operator's Manual

ELECTRICAL SYSTEM
Engine 12-Volt DC Control Circuit
The Westerbeke 35B, 38B and 42B propulsion engines have a 12-Volt DC electrical control circuit, as shown
on the wiring diagrams which follow on pages 48 to 51. Refer to these diagrams when troubleshooting or
servicing electrical components on the engine. .
CAUTION
To avoid damage to the battery charging circuit, never shut off the engine battery switch while
the engine is running.
Shut off the engine battery switch, however, to avoid electrical shorts when working on the
engine electrical circuit.
Battery Specification
The minimum recommended capacity of the battery used in the engine's 12-Volt DC control circuit is 90 -
125 Ampere-hours (minimum).
CAUTION
When quick-charging the battery with an external charger, be sure to disconnect the battery
cables from the battery. Leaving the charging circuit connected while quick-charging will
damage the alternator's diodes.
Alternator
CAUTION
When testing the alternator circuit (charging circuit), do not use a high-voltage tester such as
a megger; damaged diodes could result.
During high-speed operation of the engine, do not disconnect the positive terminal of the bat-
tery from the B terminal of the alternator, nor disconnect the negative terminal of the battery
from the ground.
When cleaning the engine with a steam cleaner, be careful to keep steam away from the al-
ternator.
Refer to pages 48 to 51 for the two electrical system wiring schematics (one is used for the Captains panel
and the other for the Admirals Panel).
Westerbeke Diesel Engines
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