Reference:
AD-55B
Enclosed AC-DC switching single output power source with battery charger (UPS Function). Universal AC input / Full range. Battery low protections. With power LED indicator and overloading protection, short-circuit and over voltage. DC voltage output: 27.6 VDC - 1.8 Amp current intensity. Battery Channel: 26.5 VDC - 0.16 Amp. Cooling by free air convection. Fixed switching frequency at 45 KHz. Output rated power: 53.92 W.