Products

NEUTRAL GROUNDING RESISTOR

NGR / NER is used to ground the neutral of Transformer / Generator to limit prospective ground fault current to a predetermined safe value. The NGR avoids transient over voltage and gives system stability under fault conditions.

Technical specification :

  • Range : 230 V to 66 kV / 8000A
  • Degree of protection : IP00 to IP65
  • Service : Indoor / Outdoor / Suitable for Highly polluting and corrosive atmosphere
  • Enclosure Finishing : Epoxy powder coat painted / Galvanized / Stainless steel (AISI 304 / 316)
  • Mounting type : Floor / Steel Structure Mounted
  • Duration : 5/10/15/30/60 Sec or Continuous
  • Frequency : 50 / 60 Hz
  • Standard followed : IEEE - 32
  • Termination : Through outdoor porcelain bushing/ cable box
  • Types of elements used : Stamped plates / Wire wound / Frame wound / Cast Iron / Edge wound
  • Resistive elements : Stainless steel (Cr – Ni) / Cr – Al alloy (AISI 416)
  • Optional accessories : CT / Monitoring Relay / Protection Relay / Space heaters / Vacuum contactor / Disconnector (Motorized/Manual) for Isolation or Changeover/ Zig zag Transformers
  • Generator Protection : Single or multiple Generators with Interlock / High resistance Grounding / Through Neutral Grounding Transformers / Disconnector or vacuum contactor Up to 11 kV
  • Maximum Temperature : 790°C
  • Ambient Temperature : 55°C



LOAD BANK

Load Bank is used to test and evaluate performance of Generators and UPS periodically, under various load conditions like full load/Inductive load/ sudden loads and Overload. Sometimes, it is used as Dummy Load for the generator to avoid Glazing of Pistons while running on very low load conditions.

Technical specification :
  • Range : Up to 12 MW
  • Degree of protection : IP 21 / 33
  • Service : Indoor / Outdoor
  • Enclosure Finishing : Epoxy powder coat painted / Galvanized
  • Mounting type : Stationary / Wheel Mounting / Trolley or Trailer Mounted / Container housing
  • Voltage : 24 V to 1500 V DC / 24 V to 33 kV for AC – 1Ph and 3 Ph
  • Frequency : 50 / 60 / 400 Hz
  • Standard followed : BS587
  • Power Factor : Resistor / Resistor – Reactive, Unity / 0.4 PF / 0.8 PF
  • Control : Local / Remote, Contactor Switching
  • Selection of Loads : Through Push Buttons or PLC / By hand held stations or By Laptop
  • Meters : Recording by Laptop / Multifunction Digital meter to indicate
  • PF/V/I/KW/KVAR/Hour
  • Ventilation : Natural / Fan cooled – Vertical / Horizontal



HARMONIC FILTER RESISTOR

Ever increasing usage of solid state devices like VFD drives and Thyristor controlled Electrical Furnaces etc causes distortion of waveforms with higher frequency Harmonics in supply system resulting in poor quality of power to end users. Harmonic filters are designed to bypass unwanted frequencies using combination of Reactor, Capacitors along with Resistor to achieve better quality power. We specialize in manufacturing medium voltage Filter Resistors for various applications starting from 11 kV onwards.

Technical specification :
  • Range : Up to 132 kV
  • Degree of protection : IP 23 made suitable for outdoor
  • Service : Outdoor
  • Enclosure Finishing : Galvanized / Stainless steel / Epoxy powder coat painted
  • Mounting type : Each phase Resistor mounted on standoff Insulator & stacked one above the other For 3 Phase configuration / Steel Structure Mounted
  • Voltage : Up to 36 kV
  • Standard followed : BS587 / IEC 60060
  • Max. Power Dissipation : Up to 2MW
  • Resistive elements : Stainless steel AISI 304 / Fecral (Al-Cr steel)
  • Maximum BIL : 400 kV
  • Design : Live tank or Earthed tank design
  • Normal creepage of porcelain insulator : 25mm/kV



SWITCH DISCONNECTOR

They are used in distribution net works for easy Isolation, RMU, Neutral Grounding of multiple Generators etc., They will come with or without Earth switch.

Technical specification :
  • Range : Up to 36 kV / 5000 A (Indoor Motorized Disconnectors up to 12000A)
  • Degree of protection : IP00 / up to IP65
  • Service : Indoor / Outdoor
  • Enclosure Finishing : Epoxy powder coat painted / Galvanized / Stainless steel
  • Mounting type : Wall / Floor / Steel Structure Mounted
  • Motorized version : Operate at 24/48/60/110/220/230 V AC / DC
  • Standard followed : IEC 62271 - 103
  • No. of Poles : 1 Pole / 3 Pole
  • Type of load : On load (Switch Disconnectors) / Offload (Disconnector)
  • Operation : Manual / Motorized
  • Other accessories : Earth switch interlocked with Main switch or Independent, Shunt Trips/Fuse with trip, Adequate auxiliary NO+NC Contacts
  • Type : Singe Break or Double Break (Centre post Rotating type) for outdoor applications



DYNAMIC BRAKING RESISTOR / POWER RESISTOR

The applications are innumerable like starting of slip ring Induction motor / Voltage dropping Resistor / Dynamic Braking Resistor for DC Motors / Traction Duty Resistors for Railways etc.,

Technical specification :
  • Degree of protection : IP00 / IP 23
  • Service : Indoor / Outdoor
  • Enclosure Finishing : Epoxy powder coat painted / Galvanized
  • Mounting type : Floor / Steel Structure Mounted
  • Data required for design : Resistance value, Discharge / Braking Duration/ Current vs. Time curve, Insulation Voltage, Degree of Protection, Duty Cycle / Duty Factor
  • Standard followed : BS587
  • Resistive Element : Stainless steel / Fecral
  • Application : Starting slip Ring Induction motor in Cranes / Pumps / Winches etc



Infrastructure

National Switchgears is synonymous with Resistors. It was established in the year 1978 and is in business of designing and manufacturing resistor for various energy control applications since then. It is a professionally managed, highly focused and an ISO company.

We are also manufacturing Switch disconnectors for both indoor and outdoor applications up to 36KV. National Switchgears stands for quality ,Engineering design, reliability and service.

Leading companies, Multinational Engineering organizations and Consultants in India are our regular customers. We have been exporting our products to well over 38 countries which include Australia, Japan, UK, South East, African and Gulf countries. The products have been tested at CPRI (India), KEMA, Netherlands for International Standards. Most of the equipments are manufactured in accordance with relevant IEC, BS and NEMA Standards.

National Switchgears was founded with very purpose of manufacturing high quality resistor for various industrial and research applications in India. Over the years many types of resistors for Traction, Neutral, Grounding, Static VAR compensation, Binary Control, Starter, Load banks and Speed controllers have been supplied to leading firms in India and Abroad. Our innovative design conforming to International specifications and quality have made us as one of the pioneering manufacturers of NGR in India. We are the first company to export NGR from India. Almost all leading consultants in India and well known consulting firms in abroad have approved our NGR.

quality

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Accomplishments :

  • Exporting our Product to more than 38 Countries.
  • Largest Exporter for Neutral Grounding/Earthing Resistor in ASIA.
  • Developed and supplied Power Resistor 4000A/1.0 Milliohm with +/- 5% accuracy for BHEL Bhopal in the year 1986.
  • Tested our NGR at KEMA, Netherland for Design validation.
  • Motorized cam controller starter for slip ring motor developed for PUB Singapore.
  • Developed Traction Resistors, an Import Substitution item for Calcutta Metro.
  • Supplied 11KV / 4000 HP starter for Slip ring Induction Motor for a Rubber Mill.
  • 400 Hz Load Bank for LCA Project for testing Fighter aircraft Engines.
  • Supplied Disconnectors 67KA / 5 SEC at 4000A / 17.5kV to Ukraine.
  • Developed High current Disconnectors up to 6300A / 17.5KV for Hydel Project.
  • Load Bank for HAL to test Aircraft Engines at - 40⁰C in Siachen Himalayas.
  • BSI Certified Organization since 2004.
  • Approved by Saudi Electricity Co. / National Grid / SABIC of Kingdom of Saudi Arabia for well over 3 decades.

about us

National Switchgears is synonymous with Resistors. It was established in the year 1978 and is in business of designing and manufacturing resistor for various energy control applications since then. It is a professionally managed, highly focused and an ISO company.

We are also manufacturing Switch disconnectors for both indoor and outdoor applications up to 36KV. National Switchgears stands for quality ,Engineering design, reliability and service.

Leading companies, Multinational Engineering organizations and Consultants in India are our regular customers. We have been exporting our products to well over 38 countries which include Australia, Japan, UK, South East, African and Gulf countries. The products have been tested at CPRI (India), KEMA, Netherlands for International Standards. Most of the equipments are manufactured in accordance with relevant IEC, BS and NEMA Standards.

National Switchgears was founded with very purpose of manufacturing high quality resistor for various industrial and research applications in India. Over the years many types of resistors for Traction, Neutral, Grounding, Static VAR compensation, Binary Control, Starter, Load banks and Speed controllers have been supplied to leading firms in India and Abroad. Our innovative design conforming to International specifications and quality have made us as one of the pioneering manufacturers of NGR in India. We are the first company to export NGR from India. Almost all leading consultants in India and well known consulting firms in abroad have approved our NGR.

COUNTRIES WHERE OUR EQUIPMENTS ARE:

Australia
Algeria
Afghanistan
Bhutan
Bangladesh
Burma
Cambodia
DR Congo
East Timor – Leste
Ecuador
Egypt
Ethiopia
Ghana
Gambia
Greece
Indonesia
Iran
Iraq
Japan
Jordan
Kenya
Kingdom of Saudi Arabia
Kingdom of Bahrain
Kuwait
Laos
Malaysia
Malawi
Mauritius
Mozambique
Myanmar
Nepal
New Zealand
Nigeria
Philippines
Qatar
Senegal
Singapore
South Africa
Sudan
Sultanate of Oman
Sri Lanka
Sweden
Taiwan
Tanzania
Thailand
Trinidad and Tobago
Turkey
Uganda
Ukraine
United Arab Emirates
United Kingdom
Vietnam
Yemen
Zambia
Zimbabwe

 

Clients

International
National

Get in Touch

Contact Info

NATIONAL SWITCHGEARS
33 (Old No. 94 - B), Sidco Industrial Estate,
Ambattur , Chennai 600 0098. India
P: 044 - 2625 44321

Regional Representatives in Abroad

Kingdom of Saudi Arabia
M/s. OLAYAN MAINTENANCE & OPERATIONS EST P.O. Box. No.: 13853, Jeddah 21414, Saudi Arabia
Tel: 00-966 2 6679930
Fax: 00-966 2 2830245
Email: mansur@olayan-tristar.com
Contact Person: Mr. K P Mansur- Vice President
GSM: +0505596708
U.A.E
M/s. SKY LIGHT ELECTRIC WARE TRDG. L.L.C. P.O. BOX NO.: 80255, SHARJAH, U.A.E
Tel: +971 6 5598948
Fax: +971 6 5598949
Email: skssharma@skylightme.net
Contact Person: Mr. S.K.SHARMA
GSM: 0097150 - 5386120
Singapore
M/s SGB STARKSTROM PTE LTD, Block 22, Woodlands Link, #04-17, Woodlands East Industrial Estate, Singapore 738734.
Tel: +65 6755 0551
Fax: +65 6755 0391
Email: sgbsin@singnet.com.sg
Contact Person: Ms. Justina Tan
GSM: +65 96169367
Malaysia
M/s SFG TECHNOLOGY (M) SDN BHD, 313, 3rd Floor B Block, Kelana Square, 17 Jalan SS7/26, Kelana Jaya, 47301 Petaling Jaya, Selangor, Malaysia.
Tel: +603 788 0 9360 / 03
Fax: +603 7 805 1652
Email: tksoon@sfg.com.my
Contact Person: Mr. T.K.SOON
GSM: +601 73820394
Indonesia
M/s. PT MEKASSEN PRATAMA, JI. Pelatnas No.: 26, Cipayung, Jakarta 13840, Indonesia.
Tel: +62 21 845 6902
Fax: +62 21 845 6902
Email: mekassen@cbn.net.id
Contact Person: Mr. Erwin
GSM: +628129251115
Sultanate of Oman
M/s General Electronics & Trading Co. L.L.C. (an OMZEST Group company) Flat No.10, 4th Floor, ‘ASMA building, Building No.1721, Way No. 2730/127, CBD Area, P.O. Box 1092, Ruwi, P.C. 112, Sultan
Tel: 00-968- 24797954
Fax: 00-968- 24797694
Email: getoman@omantel.net.om / get@omzest.com
Contact Person: Mr. Kamlesh Mehta-General Manager
GSM: +968 99326357