ISO Series Single Channel Isolated Switch

The ISO Series Single Channel Isolated Switch from the ATC Diversified Electronics Division of Marsh Bellofram is a family of single- channel devices used to provide a safe and reliable means of controlling loads from hazardous locations without releasing sufficient energy, under normal or abnormal conditions, to cause ignition of a flammable or combustible atmospheric mixture while in its most easily ignited concentration. An isolated output turns on when the control switch input from the hazardous location is closed. When the control switch input opens, the isolated output turns off. The Style A single channel plug-in devices come equipped with integral spring mating clips which secure the device to the base make this unit the only UL913 Intrinsically Safe plug-in associated apparatus available on the market today. The Style N, surface mounted enclosure is sealed with a high quality epoxy resin material and has five (5) #8-32 screw terminals.



  • Single-channel isolated switch
  • Used to safely control loads from hazardous locations
  • UL913 listed intrinsically safe plug-in device
  • Includes mating clips and base


  • Pump sequencing
  • Level control
  • Lift stations
  • Motor protection
  • Other industrial applications in hazardous environments