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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RMshebei tuya smart zigbee relay 220v wifi smart home switch circuit breaker 2P Automatic smart life 110v voltage protector 63A
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
AC 110V 220V Timer Adjustable Disconnect Delay Controller 1-480Min Timer Power-ON Delay OFF Relay Switch 7A Voltage Output
Aliexpress UK
Dual Battery Isolators also feature surge protection and a L.E.D indicator designed to alert the user when the unit is engaged. - Suitable for most 12V charging systems- Surge protection. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
eBay
KWS-303 Tuya WiFi Power Meter Smart Switch 8 in1 Energy Meter 85-290V AC Meter Timer Relay Voltage Current Electricity Meter
Aliexpress UK
Simply connect the relay between your starter battery and leisure battery and the relay takes care of everything, making sure your starter battery is not drained for when you need to get going again.
eBay
eWeLink Smart WiFi Power Energy Meter with CT Clamp AC 220V 110V Timer Relay Switch kWh Voltage Current Protector Remote Control
Aliexpress UK
Here to give You the Best Experience. We have not authorised a signature release (for your parcel to be left anywhere, unsigned for). Clear Cut Campervan Design. Here to give you the. Clearcut Campervan Design Ltd was established over 15 years ago.
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New Smart Dual Battery Isolator 12V 140A Waterproof Digital Voltage Sensitive Relay VSR Switch For Car RV Camper UTV Boat Marine
Aliexpress UK
It simply connects between the two batteries. The relay is connected between the vehicles main battery (Positive) and the leisure battery (Positive). Permanent live output (a live feed via relay from main battery + generally never used).
eBay
KWS-306 3 Phase TUYA WiFi Power Meter Over Under Voltage Protection Relay Switch Circuit Breaker Energy kWh Meter Smart Life
Aliexpress UK
Suitable for most 12V charging systems- Surge protection. Dual Battery Isolators also feature surge protection and a L.E.D indicator designed to alert the user when the unit is engaged. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
eBay
220V 230V Tuya WiFi Smart Circuit Breaker Leakage Over Under Voltage Protector Relay 2P 63A Power Energy kWh Meter Switch Timer
Aliexpress UK
Dual Battery Isolators also feature surge protection and a L.E.D indicator designed to alert the user when the unit is engaged. - Suitable for most 12V charging systems- Surge protection. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
eBay
Tuya Smart WiFi Circuit Breaker 1P+N 63A Timer Relay Power Energy kWh Meter Over Current Voltage Protector Remote Control Switch
Aliexpress UK