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SvWhy separate the batteries?
How a battery isolator relay works
To ensure that you can always start the engine, the starter battery should be automatically separated from the consumer batteries when the engine is switched off.
The easiest and cheapest way to achieve this is to use a disconnect relay.
A separator relay works like a remote switch and connects to the starter key. When you turn the starter key to start the engine, the relay switches on and connects the starter and consumer batteries so that both are charged.
When you switch off the engine, the separator relay switches off so that your consumers cannot discharge the starter battery. This ensures that you always have power in your starter battery when you start the engine.
You can read about how to install your isolating relay here
