ASCO Model 172 (Edco PHC Series) Surge Protective Device

The ASCO Model 172 Surge Protective Device is designed to protect two pairs of wires specifically for alarm and security systems where operating currents can be as high as 5 Amps. Electrically, the Model 172 is a rugged series hybrid implementing a staged complement of MOVs, copper wound inductors and Silicon Avalanche Diodes. This design reduces series resistance to 0.2 ohms per pair. These products are intended to mate with a PCB1B gold-plated female terminal connector accessory.


  • Three-stage hybrid protection
  • Differential protection
  • Common mode protection
  • Plug-in module
  • Automatic recovery
  • Fast response time
  • Continuous current up to 5 Amps
  • Requires accessory PCB1B base
  • PTU (Pass Thru Unit) availablefor troubleshooting


  • 5 Year Warranty

Technical Specifications