Purkeys’ new SteadyCharge accessory battery charger will monitor and maintain accessory batteries that support trailer refrigeration and heating units.

Inactive batteries will naturally discharge over time and can drain during seasonal periods when dependent engines are not running, the company says. The parasitic loads from built-in telematics systems can also drain starter batteries within just a few days when sitting idle.

SteadyCharge will maintain the batteries for months without overcharging them, and will run whenever the tractor is connected to the trailer. No extra charging cables are required, and the system automatically charges the system using an existing seven-way cable without interfering with other devices on the auxiliary circuit.

Purkeys says it will extend the lifespan of existing batteries by up to 500%.

SteadyCharge units weigh 10 lb., meet SAE J1455 testing criteria, and are IP66 rated for exterior mounting on the trailer body. Their logic controllers include a low-voltage disconnect to protect tractor batteries and can be programmed to any related setpoint. Temperature-compensated charging also optimizes charging characteristics to match the operating climate.