Battery charger and trickle-charger LG66-30 has been developed for work trains and railway maintenance vehicles. Charging is based on UIUa characteristic curve and temperature compensated. The device is microprocessor controlled, has short-circuit and over temperature protection. The special feature of this air-cooled charger is that it has no moving mechanical parts for cooling (no fan). LED's inform permanent about the status of device and battery. The two-line display shows the current charging parameters, such as voltage, current, battery capacity and loading time. The charger is completely mounted on shock dampers to absorb impact and vibrations.