These chargers by Ametek (Prestolite Power/Hobart) are the leading industrial ferroresonant battery chargers. The ferroresonant transformer is the heart of the efficient charger. The power conversion circuitry is designed to maximize battery life with its constantly tapering charge, automatically regulated by the "on charge" battery voltage. The output current of the charger is determined by the state of discharge of the battery. The battery is precisely charged, based on its depth of discharge.
Silicon Controlled Rectifier (SCR) type battery chargers regulate charging current by allowing the battery to determine its own charge cycle rate in accordance with its state of discharge. SCR chargers provide a constant current-constant voltage-constant current (I-E-I) charge that eliminates the possibility of overcharging, even with line voltage variations of +/- 10%, and allows the battery to finish at the proper current regardless of its age or temperature.
High frequency industrial battery chargers utilizing IGBT technology offer high efficiency, precisely controlled charge curves, light weight and small size. High frequency chargers provide a constant current-constant voltage-constant current (I-E-I) charge curve. Because of their extreme flexibility, they are adaptable to all types of batteries and applications.