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Battery combining relays


Why separate the starter battery from the secondary battery?

In each vehicle with a combustion engine there is a starter battery. If you have several batteries in a vehicle, to feed additional power consumers, it is necessary to properly distribute the charging current to the batteries. Obviously, the starter battery needs to be charged first, so the engine can always be started. Then, the secondary battery, or accessory battery, for example bow thruster battery, is recharged. Therefore, the batteries are separated by an isolating relay, also called battery separator.

The operation of a battery separator

The microprocessor controlled battery separator monitors the voltage of the starter battery. As long as the voltage of the starter battery is too low, thus not fully charged, the battery separator will direct the charge current to the starter battery only. When the starter battery has reached its maximum voltage for more than 7 seconds, the battery separator will also distribute charging current to the secondary or accessory battery. Accessories in, for example, a vehicle or vessel are powered by such a battery. When the engine of a camper or boat is switched off, the voltage of the batteries drops over time. If this voltage is less than a certain value for over 60 seconds, the battery separator will separate the batteries again. This way the starter battery will remain charged.

Bipolar operation of the Cellpower Battery Separator

The Cellpower Battery Separators have a unique feature. If the accessory or secondary battery in your boat, camper or caravan, is charged with a battery charger, the Cellpower Battery Separator will also distribute current to the starter battery. This function is only activated provided that the secondary or accessory battery is fully charged. Once the charger is no longer connected to the accessory or secondary battery, the battery separator will disconnect the batteries again. Thus the Cellpower Battery Separator works bipolar, current can be directed in two directions.

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Edwin van Oosten

Area Sales Manager Export
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