MTL7700 Series
Safety Barriers

All MTL7700 Series barriers are based on the same simple principle. Each channel contains two stages of pulse-tested Zener or forward connected diodes and an ‘infallible’ terminating resistor. In the event of an electrical fault in the safe area, the diodes limit the voltage that can reach the hazardous area and the resistor limits the current. A fuse protects the diodes, and the two stages of voltage limitation ensure continued safety if either stage should fail. No active output current limiting circuits are employed. All models are certified ‘ia’ for all zones and ‘IIC’ for all explosive atmospheres (except MTL7707P+ and MTL7729P+, ‘ia’ ‘IIB’).