Littelfuse - Model PGR-5330 Series -Neutral-Grounding-Resistor Monitor

The PGR-5330 is an advanced ground-fault and resistor monitoring relay. The PGR-5330 measures neutral current, neutral-to-ground voltage and neutral resistance. It provides continuous monitoring of the neutral-to-ground path to ensure the neutral-grounding resistor (NGR) is intact. This is of utmost importance on resistance-grounded systems because NGR failure renders current-sensing ground-fault protection inoperative.