MTL7728+|  Instruments | Proximity Detector Interface

  All MTL7700 series Zener barriers are based on the same design principles. Each channel contains a secondary pulse detecting Zener or forward connecting diode and a “reliable” terminating resistor. In the event of an electrical fault in the safety zone, the diode limits the voltage that can reach the hazardous area, while the resistor has a current limiting effect. A fuse protects the diode, and a two-stage voltage limiting function ensures continuous protection in the event of a failure in either stage. No active output current limiting circuitry is used. All models are certified “ia” - for all zones and “IIC” - for all explosive atmospheres (except MTL7707P+ and MTL7729P+, “ia” “IIB”).