Battery - Yanmar 3YM30 Sevice Manual

12.2 Battery

The new type instrument panels are applied for 3YM30 series engines. The features are compactness,
waterproof and independence from pulse by ring gear teeth number.
The engine speed, indicated with the instrument panel is activated by the pulse from flywheel ring gear.
The engine speed with new panel is activated by alternator B terminal pulse.
(1) Battery capacity
Battery capacity (5 hours rating)
(2) Battery cable
Wiring must be performed with the specified electric wire. Thick, short wiring should be used to connect
the battery to the starter. Using wire other than that specified may cause troubles.
The overall length of the wire between the battery (+) terminal and the starter (B) terminal, and between
the battery (-) terminal and the starter (E) terminal, should be determined according to the following
table.
Voltage system
12 V
Note :
Excessive resistance in the key switch circuit (between the battery and start [S] terminals) can cause
improper pinion engagement. To prevent this, follow the wiring diagram carefully.
Allowable wiring voltage
drop
0.2 V or less/100A
12V-64 AH or more (type 95D31L equivalent)
Conductor cross section
area
2
20 mm
2
40 mm
185
12. Electrical System
Allowable overall length
Up to 2.5 m
Up to 5 m