Used and out of box transformer, 400w, Short and Overcurrent Protection. The TP-VC277-220VAC voltage converter changes 277VAC to 220VAC 400W. 277VAC is a voltage commonly found on light poles, including light poles on streets and parking lots. This voltage is typically too high to run common equipment such as outdoor UPS systems, security cameras and wireless equipment. By converting the voltage to 220VAC, most common equipment can be powered.