When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery. So it does not drain your main starter battery and you will always be able to start your vehicle.
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DC 12V 24V 100A 200A WM686 Universal Relay 4 Pin Normal Open Car Starter Relay for Battery ON/Off Split Charge Relay Switch
Aliexpress UK
We are an approved Durite UK Distributor. Allows split charging of second battery bank without discharging the primary/start battery, relay makes at 13.3 volts and breaks at 12.65 volt. 12 volt 140 amp.
eBay
1PC 12V 200 Amp Heavy Duty Split Charge/Winch Relay for Car Van Boat 4 Pin 80*42*42mm
Aliexpress UK
A VSR is a relay that separates the car's main cranking battery and the secondary accessories battery. The VSR is triggered by detecting when the alternator is running and charging the car battery. When the VSR detects that the car is on, it says "Hey the car's on!
eBay
CNSPEED Smart Dual Battery Isolator 12V 140A Voltage Sensitive Relay VSR Split Charge with Digital Voltmeter For Camper Car RV
Aliexpress UK
When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery. So it does not drain your main starter battery and you will always be able to start your vehicle.
eBay
1Pcs Relay VSR for Camper Car Smart Battery Isolator 12V 140A Voltage Sensitive Split Charge for Car RV ATV Yacht
Aliexpress UK
When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery. So it does not drain your main starter battery and you will always be able to start your vehicle.
eBay
DC 10-110V Voltmeter Coulomb Meter 30A Relay Automatic Battery Charge Discharge Voltage Current Tester Battery Level Indicator
Aliexpress UK
A VSR is a relay that separates the car's main cranking battery and the secondary accessories battery. The VSR is triggered by detecting when the alternator is running and charging the car battery. When the VSR detects that the car is on, it says "Hey the car's on!
eBay
When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery. So it does not drain your main starter battery and you will always be able to start your vehicle.
eBay
Note: The benefit of this type of relay is that it does not require a connection to the alternator or any modifications to the existing vehicle electrical system. Pressure Monitoring Systems. Car Care & Cleaning.
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