Volvo TAMD74C, Operator'S Manual

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Maintenance: Electrical system
Electrical system
The engines are equipped with a bipolar electrical system with alternator. System voltage is 12 alternatively 24V.
WARNING! Before starting work on the electrical system, the engine must be stopped and the power
turned off with the main switch/switches. Shore power to the engine heater, battery charger or other extra
equipment fitted on the engine must be disconnected.
Main switch
The main switch must never be turned off until the en-
gine has been stopped. Breaking the circuit between
the alternator and the battery while the engine is run-
ning can damage the alternator. For the same rea-
son, the charge circuits must never be switched while
the engine is running.
IMPORTANT! Never turn the power off using
the main switch while the engine is running.
Fuses
The engine is equipped with two semi-automatic fus-
es that cut the current when there is an overload (the
engine will stop if either of the fuses break).
The fuses are located on the main electric terminal
box on the left side of the engine and are reset by
pressing the buttons.
There is a 7.5 A fuse (A) inside the terminal box for
the EDC system.
Contact an authorized Volvo Penta workshop if a fuse
often breaks to determine the cause of the overload.
Electrical connections
Also check that all electrical connections are dry and
free of oxidation and that there are no loose connec-
tions. If necessary, spray these connections with a
water-repellent spray (Volvo Penta Universal oil).