{"id":856,"date":"2026-08-27T05:49:14","date_gmt":"2026-08-27T05:49:14","guid":{"rendered":"https:\/\/demos2us.in\/electric\/?post_type=product&p=856"},"modified":"2026-08-27T05:49:14","modified_gmt":"2026-08-27T05:49:14","slug":"neutral-grounding-resistors","status":"publish","type":"product","link":"https:\/\/demos2us.in\/electric\/products\/neutral-grounding-resistors\/","title":{"rendered":"Neutral Grounding Resistors"},"content":{"rendered":"

Neutral Grounding Resistors<\/strong>\u00a0(NGR<\/strong>s) are\u00a0utilized\u00a0to\u00a0restrict\u00a0fault\u00a0currents,\u00a0ensuring\u00a0the safety of both equipment and\u00a0personnel\u00a0within\u00a0industrial\u00a0systems.Positioned between he\u00a0neutral\u00a0point and ground, NGRs\u00a0elevate\u00a0the\u00a0overall\u00a0resistance in\u00a0case\u00a0of an earth\u00a0fault,\u00a0thus\u00a0constraining the current to a\u00a0secure\u00a0magnitude.<\/p>\n

Advantage<\/strong>s of NGRs include:<\/strong><\/p>\n

Reduce\u00a0the single\u00a0phase\u00a0fault currents and secure eachpiece\u00a0of equipment in MV electrical\u00a0networks,<\/p>\n

Reduce the\u00a0transient\u00a0over\u00a0voltages which can\u00a0occur\u00a0during an earth fault, and be\u00a0monitored and used to\u00a0activatethe earth fault\u00a0relay,<\/p>\n

Increase protection of\u00a0generators,\u00a0transformers and\u00a0relatedequipment,<\/p>\n

Reducedoperation\/maintenance\u00a0costs,<\/p>\n

Increase safety,<\/p>\n

Provide simple,\u00a0reliable, selective means of protection,<\/p>\n

Allows the use of equipment, and in particular\u00a0cables with lower\u00a0insulation\u00a0levels than for an insulated neutral\u00a0scenario<\/p>\n

Reduce the\u00a0step\u00a0voltage<\/p>\n

The fault current value should be\u00a0limited to a value that can be safely\u00a0handled by the machine or transformer. It also needs to be high enough to be\u00a0sensed by the earth fault protection\u00a0relays. If the NGR resistance value is too high, the fault current will be very low and will not be able to\u00a0activate\u00a0the earth\u00a0fault\u00a0protection relay during earth fault conditions.<\/p>\n

In a\u00a0three phase star\u00a0connection, the\u00a0capacitances are\u00a0formed with the ground. In the event of an earth fault, these capacitances may get\u00a0charged with the line voltage and may cause\u00a0transient\u00a0over voltages. The NGR should have a value that\u00a0permits a let-through current which\u00a0enables the capacitances to\u00a0discharge.<\/p>\n

The resistances are also\u00a0categorized by the time that they can\u00a0withstand\u00a0the fault current.\u00a0Typical\u00a0durations are 5-10\u00a0seconds. The\u00a0extended time\u00a0rating\u00a0resistors are used in systems where the\u00a0reliability\u00a0of the system is\u00a0critical, e.g.\u00a0petroleum\u00a0industries,\u00a0mines, etc. In these\u00a0situations, high\u00a0resistances are used for\u00a0withstanding long periods of\u00a0earth fault. When an earth fault\u00a0occurs in one\u00a0phase, an\u00a0alarm\u00a0will be\u00a0generated. However, the system continues to run until the next\u00a0scheduled\u00a0shutdown.<\/p>\n

Neutral Earthing Resistors\u00a0<\/strong>are designed to\u00a0absorb\u00a0a large\u00a0amount of energy\u00a0without\u00a0exceeding\u00a0temperature limitations\u00a0defined in IEEE 32. weifan NGRs can be used in both\u00a0indoor\u00a0and\u00a0outdoor settings. The neutral point is connected with a\u00a0porcelain\u00a0bushing\u00a0or a high\u00a0voltage\u00a0(XLPE)\u00a0cable, typically (minimum\u00a0cross-section\u00a0= 70mm2\u00a0copper\u00a0or 95mm2\u00a0aluminium) from the\u00a0bottom,\u00a0top\u00a0or\u00a0side. The most\u00a0common protection\u00a0degree\u00a0preferred for NGRs is IP 23 as it allows the resistor\u00a0elements to cool more easily. Because the resistor elements are\u00a0comprised completely of\u00a0stainless steel, they are\u00a0capable\u00a0of withstanding\u00a0extreme\u00a0environmental\u00a0conditions and\u00a0thus\u00a0suitable\u00a0for both the\u00a0seashore\u00a0and\u00a0desert. NGRs are\u00a0shipped with\u00a0maintenance\u00a0and\u00a0installation\u00a0guidelines which include\u00a0recommended\u00a0relay settings. weifan provides complete technical\u00a0assistance\u00a0in order to meet your\u00a0specifications or site conditions.<\/p>\n

NG<\/strong>R<\/b>\u00a0<\/strong>Options<\/strong><\/p>\n

Elevated support stands are provided for ground\u00a0clearance\u00a0and safety<\/p>\n

Specially designed\u00a0units for\u00a0hazardousand\u00a0extreme locations (Ex-proof, ATEX\u00a0certified)<\/p>\n

Stainless steel or aluminium\u00a0enclosures on\u00a0demand<\/p>\n

Installation\u00a0of voltage transformers<\/p>\n

Installation of protection\u00a0relays<\/p>\n

Porcelain\u00a0entrance\u00a0bushings can be\u00a0mounted on the top or on the side of\u00a0enclosure<\/p>\n

Grounding transformer installation<\/p>\n","protected":false},"featured_media":857,"template":"","product_category":[7,8],"class_list":["post-856","product","type-product","status-publish","has-post-thumbnail","hentry","product_category-power-resistors","product_category-neutral-grounding-resistor"],"acf":[],"_links":{"self":[{"href":"https:\/\/demos2us.in\/electric\/wp-json\/wp\/v2\/product\/856","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/demos2us.in\/electric\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/demos2us.in\/electric\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/demos2us.in\/electric\/wp-json\/wp\/v2\/media\/857"}],"wp:attachment":[{"href":"https:\/\/demos2us.in\/electric\/wp-json\/wp\/v2\/media?parent=856"}],"wp:term":[{"taxonomy":"product_category","embeddable":true,"href":"https:\/\/demos2us.in\/electric\/wp-json\/wp\/v2\/product_category?post=856"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}