The MS1-12Ex0-R is a single-channel switching amplifier with intrinsically safe input circuits. The output circuit consists of one DPDT relay. The output function is jumper programmable on terminals 11/ 12 for direct mode ( N.O.) or inverse mode ( N.C.) ( See chart below) . This unit does not have input circuit monitoring. It is an inexpensive alternative in systems that use NAMUR sensors or mechanical contacts as input devices.