Pure Sine Wave Inverter Telecommunication Power Inverter.The series are designed specifically for post and telecommunications industry for 48V,-48V or 24V DC panel of program-controlled switchboards, computer rooms, etwork, billing, server, and emergency lighting and other places. Normally, AC powers to critical loads through the static switch power supply. Once the power cut or other abnormal conditions beyond the normal range, electrical equipment power supply will shift to the DC (battery) of inverter power.