Description

High-resistance grounding prevents many of the problems

that are associated with ungrounded and solidly grounded

electrical distribution and utilization systems. High-resistance

grounding can limit point-of-fault damage, eliminate transient

overvoltages, reduce the arc-flash hazards, limit voltage

exposure to personnel, and provide adequate tripping levels

for selective current-based ground-fault detection and

coordination.

The Littelfuse Neutral Grounding Resistor System is a

neutral grounding resistor (NGR), current transformer, and

sensing resistor installed in a NEMA 3R enclosure used to

high-resistance ground transformers and generators. The

NGR system is designed for use with Littelfuse Neutral

Grounding Resistor Monitors for complete system grounding

and grounding protection.

The NGR series – US systems are designed for use in US

applications and all other parts of the world, not including

Canada. For applications in Canada, please use the NGR

series – Canada.

Applications

High-resistance grounding is applied on transformers and

generators where safety and continuity of service are

important. A faulted feeder may remain in operation until it

is safe to repair the fault, where allowed by the local

electrical code.