ZSM1 is a basic vacuum switch with 1 output. No analog output is included. Solid state and contact reed switch options are available,with different voltages. The switch output turns ON when vacuum is greater that the set point. A red LED indicator also light to correspond with the output signal. A rotary trimmer adjusts the switch set point. ZSM1 can be mounted in a ZM generator unit, or piped by metric or NPTF male threads. Electrical connection is made by a 2 or 3 wire cable. This switch is compatible with any non-corrosive, non-flammable gas.