PGR-6101 Series – Ground-Fault and Insulation Monitor Series - Littelfuse PGR-6101 Relays Provide Superior Ground-Fault Protection

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The PGR-6101 series relay operates on one- or three-phase solidly grounded, resistance-grounded, and ungrounded ac systems up to 6 kV. This relay combines the features of a ground-fault protection relay and insulation monitor into one unit. It protects against ground-faults by monitoring insulation resistance when the motor is de-energized and by monitoring ground-fault current when the motor is energized. The PGR-6101 features two separate analog outputs for optional current and ohm meters as well as two separate alarm relays.


  • Adjustable GF pickup (30–200 mA)
  • Adjustable insulation pickup (60–600 kΩ)
  • Adjustable time delay (50–250 ms)
  • Output contacts
  • Analog outputs (0–1 mA)
  • CT-loop monitoring
  • Selectable contact operating mode
  • POWR-GARD® technology

Access specifications, certifications, check availability and order parts below

Catalog #Supply
Relay Contacts ConfigIEEE Device NumbersRelay
DimensionsWeight (lbs/g)Conformally coatedGF Trip Level AGF Trip Time sHarmonic FilteringReset TypeTest ButtonSamples
PGR-6101-120120N/A2 Form C (N.O./N.C.)50G - 50N - 51G - 51N - 64 - 74Fail-safe / Non Fail-safe3 H x 3.9 W x 4.5 D in.0 KgOptional0.03 - 0.200.05 - 0.25YesFront-panel switchFront-panel switchOrder
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