Disconnect relays

Battery Separator for Multiple Batteries

  • Distribution of charging current
  • Starter battery first

Vehicles with a combustion engine operate with a starter battery. If there are additional batteries to power other electrical consumers, it is essential to distribute the charging current evenly across all batteries. The starter battery must always be charged first to ensure the vehicle can start. The accessory battery is charged afterwards. Therefore, the batteries must be separated using a separation relay, also known as a battery separator.

Separation Relay: How Does It Work?

The microprocessor-controlled battery separator monitors the voltage of the starter battery. As long as the voltage of the starter battery is too low and not fully charged, the battery separator will only allow the charging current to flow to the starter battery. If the starter battery reaches maximum voltage for more than 7 seconds, the battery separator will also allow charging current to flow to the accessory or service battery. Accessories in a vehicle or boat, for example, are connected to this battery. When the engine of the vehicle, such as a camper, caravan, or boat, is turned off, the voltage of the batteries will gradually drop over time. If this voltage remains below a certain value for at least 60 seconds, the battery separator will separate the starter battery from the accessory or service battery again. This keeps the starter battery charged. Looking for personal advice from a professional?

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Separating the Starter Battery from the Accessory Battery with a Separation Relay

Every vehicle with a combustion engine has a starter battery. If multiple batteries are installed in such a vehicle to power extra electrical consumers, it is necessary to distribute the charging current properly across the batteries. Naturally, the starter battery must always be charged first to start the vehicle. The second battery, whether it’s an accessory battery or, for example, a bow thruster battery, is charged afterwards. Therefore, the batteries must be separated using a separation relay, also known as a battery separator.

Cellpower Battery Separation Relay with Bipolar Functionality

The Cellpower Battery Separators have a unique functionality. If you charge the accessory or service battery of your boat, camper, or caravan with a battery charger, the Cellpower Battery Separator will also charge the starter battery. This happens only if the accessory or service battery is fully charged. Once the battery charger is disconnected from the accessory or service battery, the battery separator will decouple the starter battery from the other battery. The Cellpower Battery Separator works in a bipolar manner, allowing current to flow in either direction.

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