Retrofitting An Existing System
Existing 1-2-Both Switch
Drawing AT9610286 shows the circuit for retrofitting a system using an existing battery selector switch. The switch, S1 is now used as an emergency parallel switch, and should be left in the #1 position which selects the house bank. When needed, the switch can be placed in the both position to start the engine from the house bank. If desired, S2 can be turned off to prevent connecting the starter battery to DC distribution. S1 can also be turned off to disconnect the DC breaker panel.
Alternator Wiring
Note that the alternator is re-wired directly to the house bank. This can be done as shown, or the wire from the alternator can be connected at the switch.
Starter Battery Wiring
The starter is wired directly to the starter battery, as shown. A separate disconnect switch may be used as an emergency shut-off, or as a security device.
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