The 1820-50-A3 is a signal and dataline protector designed to safeguard sensitive electronic circuits from damaging surge voltages and currents. It operates with a 50 V signal voltage, supports a maximum data rate of 4 MHz, and has a series resistance of 51 Ohms. This multi-stage protector features a fast response time of 50 picoseconds, provides a peak clamping voltage of 89 V at 1000 A, and can handle a load current of 100 mA. It is specifically designed for use with differential signals like RS-422 and RS-485, as well as 4-20 mA current loops in industrial controls and data communication systems. The unit comes with a DIN-3 clamp for convenient rail mounting.