Type 64 Ground Relay

Full DataSheet and Specs:

The SWARTZ Type 64 Ground Relay provides dual functions for high resistance grounded DC switchgear. The 64r relay is designed to protect equipment enclosures and alert personnel to”ground” and “hot” fault conditions in DC switchgear and rectifiers. These high resistance relays provide superior performance and operational reliability through solid state components, rugged construction and self-diagnostic features.


  • Draw-out construction
  • LED Meter - Accurate, easy to read
  • Transient Surge Protection
  • Detects AC or DC “hot structure” faults
  • Internal Power Supply operates on and auto compensates for a wide range of DC inputs
  • Internal Time Delays to prevent nuisance tripping


The Swartz Type 64r High Resistance Structure Ground Relays alert personnel visually and through alarm output contacts when a DC switchgear structure or rectifier becomes grounded through a breach in the insulation. Annunciation occurs when the voltage sensing trip system has been by passed by grounding or when the relay’s self-diagnostic feature determines that and internal failure has occurred. The relay also alerts personnel when a leakage or fault occurs between the bus and structure (hot structure). Normally, the output is connected to a lockout relay to automatically de-energize the entire station. The hot structure function detects both AC and DC leakages and faults. Setpoints for ground structure annunciation and hot structure trip are adjustable. Test buttons for both ground structure annunciation and hot structure trips are provided on the front panel. In the event of a fault and a lockout condition does not occur, the Structure Ground Relay will provide continuous operation if voltage does not exceed 800 VDC or 700 VDC with 600 VAC superimposed (rectifier faults).