NGR - Littelfuse

NGR Series - Neutral Grounding Resistor System

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Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse. "Littelfuse" includes Littelfuse, Inc., and all of its affiliate entities.

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 – Canada systems are specifically designed for use in Canadian applications.

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.

Access specifications, certifications, check availability and order parts below

Catalog #	CT secondary current Amps	Input Voltage (V)	Mounting Method	Weight (lbs/g)	built in CTs	Frequency	Input Current Range (A)	Input Impedance (Ohms)	NEMA Rating	Response Time (ms)	Sense Resistance (Ohms)	Stock

NGR1036	0.05	480	Floor Mount	0 Kg	No	60	5	55.4	3R	Continuous	ER-600VC	Check
NGR1038	0.05	600	Floor Mount	0 Kg	No	60	5	69.4	3R	Continuous	ER-600VC	Check
NGR1041	0.05	480	Floor Mount	0 Kg	No	60	2	138	3R; Weather Protected Sensing Resistor	Continuous	ER-600VC	Check
NGR1045	0.05	600	Floor Mount	0 Kg	No	60	5	69.4	3R; Weather Protected Sensing Resistor	Continuous	ER-600VC	Check
NGR1050	0.05	480	Floor Mount	0 Kg	No	60	2	138	3R	Continuous	ER-600VC	Check
NGR1051	0.05	480	Floor Mount	0 Kg	No	60	5	55.4	3R; Weather Protected Sensing Resistor	Continuous	ER-600VC	Check
NGR1052	0.05	600	Floor Mount		No	60	2	173.5	3R	Continuous	ER-600VC	Check
NGR1053	0.05	600	Floor Mount		No	60	2	173.5	3R; Weather Protected Sensing Resistor	Continuous	ER-600VC	Check
NGR1066	0.05	4160	Floor Mount		No	60	5	480.9	3R	10 s	ER-5KV	Check
NGR1067	0.05	4160	Floor Mount	0 Kg	No	60	5	480.9	3R; Weather Protected Sensing Resistor	10 s	ER-5WP	Check
NGR1068	0.05	4160	Floor Mount		No	60	5	480.9	3R	Continuous	ER-5KV	Check
NGR1069	0.05	4160	Floor Mount		No	60	5	480.9	3R; Weather Protected Sensing Resistor	Continuous	ER-5WP	Check
NGR1070	0.05	4160	Floor Mount		No	60	10	240.5	3R	10 s	ER-5KV	Check
NGR1071	0.05	4160	Floor Mount		No	60	10	240.5	3R; Weather Protected Sensing Resistor	10 s	ER-5WP	Check
NGR1072	0.05	4160	Floor Mount		No	60	10	240.5	3R	Continuous	ER-5KV	Check
NGR1073	0.05	4160	Floor Mount	0 Kg	No	60	10	240.5	3R; Weather Protected Sensing Resistor	Continuous	ER-5WP	Check
NGR1074	0.05	4160	Floor Mount	0 Kg	No	60	15	160.3	3R	10 s	ER-5KV	Check
NGR1075	0.05	4160	Floor Mount		No	60	15	160.3	3R; Weather Protected Sensing Resistor	10 s	ER-5WP	Check
NGR1076	0.05	4160	Floor Mount		No	60	15	160.3	3R	Continuous	ER-5KV	Check
NGR1077	0.05	4160	Floor Mount		No	60	15	160.3	3R; Weather Protected Sensing Resistor	Continuous	ER-5WP	Check
NGR1078	1	4160	Floor Mount		No	60	25	96.2	3R	10 s	ER-5KV	Check
NGR1079	1	4160	Floor Mount	0 Kg	No	60	25	96.2	3R; Weather Protected Sensing Resistor	10 s	ER-5WP	Check
NGR1080	1	4160	Floor Mount		No	60	25	96.2	3R	Continuous	ER-5KV	Check
NGR1081	1	4160	Floor Mount		No	60	25	96.2	3R; Weather Protected Sensing Resistor	Continuous	ER-5WP	Check