Nitrogen Injection Fire Protection System (NIFPS) for Oil filled Power Transformer

What is Nitrogen Injection Fire Protection System (NIFPS)?

Nitrogen Injection Fire Protection System (NIFPS) is a fire protection system which prevent oil tank explosion or rupture and possible oil fire in event of minor nature of arcing due to internal faults in Oil filled Power transformer.

It also prevent damage to transformer and accessories in case of fire by external causes such as bushing fire, OLTC fire, fire from surrounding equipment etc.

Nitrogen Injection Fire Protection System

Important equipment and devices of The Nitrogen Injection Fire Protection System

  • Fire Extinguishing Cubicle (FEC) with pressurized Nitrogen Cylinder
  • Control Box for NIFPS
  • Fire Detector or Linear Heat detectors on top cover of the transformer
  • Transformer Conservator Isolation Valve (TCIV) between Buchholz relay and Conservator
  • Signal box on transformer
  • Interconnecting piping between fire extinguishing cubicle to transformer tank for Oil Drain and Nitrogen Injection
  • Cabling between signal box to control box and from control box to fire extinguishing cubicle as well as from fire detector to signal box/control box/FEC including supply of required type of Copper Conductor, armoured fire survival cables of 1.1kV voltage grade

Working Principle of Nitrogen Injection Fire Protection System (NIFPS)

The system shall have Fire Extinguishing Cubicle (FEC) placed on a plinth at a distance of 5-10 m away from transformer or placed next to the fire wall.

The FEC shall be connected to the top of transformer main oil tank for depressurization of tank and to the oil pit (capacity is approximately equal to 10% of total volume of oil in transformer) from its bottom through oil pipes. The fire extinguishing cubicle shall house a pressurized nitrogen cylinder which is connected to the oil tank of transformer at bottom.

The transformer Conservator Isolation Valve (TCIV) is provided between the conservator tank and Buchholz relay.

Cable connections are to be provided from signal box to the control box, from control box to fire extinguishing cubicle and from TCIV to signal box.

Fire detectors placed on the top of transformer tank are to be connected in parallel to the signal box by Fire survival cables.

Control box shall be connected to High Voltage switchgear located in substation for receiving system activation signals.

Earth points shall be provided on control box and Fire Extinguisher cubicle and shall be verified for system isolation.

Operation philosophy of Nitrogen Injection Fire Protection System (NIFPS)

The automatic Detection & Extinguishing System shall be designed such that in the event of fire occurring at any place on transformer, it shall be detected by fire detectors fitted on the top of transformer.

Fire shall be quenched within 3 minutes (maximum) of system activation and within 30 seconds (maximum) of commencement of nitrogen injection.

Fire detection signals are received from signal box to relay panel in control box for system activation. On receipt of all activating signals, the system shall drain predetermined volume of hot oil from the top of tank, through transformer top oil filtration valve to reduce tank pressure by removing top oil and simultaneously injecting Nitrogen gas at high pressure for stirring the oil at pre-fixed rate and thus bringing the temperature of top layer down.

Transformer Conservator Isolation Valve blocks the flow of oil from conservator tank in case of actuation of NIFPS.

Nitrogen occupies the space formed by oil drained out and acts as an insulating coat over oil in the tank and consequently preventing aggravation of fire.

Potential free terminal connection for transformer isolation circuit breakers, differential relay, buchholz relay, PRV, oil surge relays shall be connected directly from switchgear located in nearest substation to the Control Box.

The control system shall be intelligent automatic self-sufficient system without any external control/logic from DCS/PLC.

The system shall be connected to Electrical Control system for display of “Fire”, “Fault” and “Cylinder Pressure Low” signals.

The above stated signals, common for each transformer shall be terminated in the junction box.

Additionally, for monitoring the health of each nitrogen cylinder, the system shall be in a position to reflect the cylinder pressure uniquely by pressure gauge locally.

Also, the signals from the pressure switch for the same shall also terminate in a junction box.

Logic diagram and P&IDs for the nitrogen injection system shall clearly indicate the operation of the system.

Activation and Control system Philosophy of Nitrogen Injection Fire Protection System (NIFPS)

The activation and control signals of nitrogen fire protection system shaft be designed in a way to achieve zero probability of malfunctioning of fire prevention and extinguishing system to avoid any chances of interruption in power supply.

The NIFPS shall be provided with automatic control for fire prevention and fire extinction. Remote electrical push button control at Control Box and local manual control in the fire extinguishing cubicle shall also be provided additionally.

The following electrical-signals shall be required for activating the fire protective system under prevention mode and fire extinguishing mode.

Auto Mode

For prevention of fire:

— Differential relay operation

— Buchholz relay paralleled with pressure relief valve, oil surge relays

— Tripping of all circuit breakers (on Primary & secondary side) associated with transformer is the pre-requisite for activation of system.

For extinguishing fire:

— Fire detector or Linear heat detectors (LHD)

— Buchholz relay paralleled with pressure relief valve, oil surge relays

— Tripping of all circuit breakers (on HV &LV side) associated with transformer is the prerequisite for activation of system.

Manual Mode

Local & Remote

— Tripping of all circuit breakers (on HV & LV side) associated with transformer is the prerequisite for activation of system.


— Tripping of all circuit breakers (on HV &LV side) associated with transformer is the prerequisite for activation of system.

— The system shall be designed to be operated manually in case of failure of power supply to fire protection system.

Share with

This Post Has 36 Comments


    As per applicable standard, like the IEC or NFPA, when having this system, then no need for any other system to fight a feasible oil fire, caused by external factors? – e.g. applying a water-mist system or equivalent? – in case no need, could you refer to applicable standards, please?

  2. Can I set the transformer protector to out of service while energized? If so, what are the preparatory steps if there are, so that the transformer wont trip? Thank you.

  3. What are the preparatory steps to be done before setting to “out of service” in the control panel of an energized transformer?Our HICO brand 100mva transformer was intalled in 2009 with TPC transformer protector, but we were left without training and operation manual.

  4. Chelsey

    It’s genuinely very complicated in this active life to
    listen news on Television, theefore I only use web for that reason, and obtain the hottest information.

  5. AlenaPetrovna

    Можем предложить услугу:
    “Ликвидация онлайн-сайтов ваших конкурентов!”
    Спрашиваете, каким способом это можно реализовать?!
    – Практический опыт наших специалистов – десять лет.
    – Конфиденциальная разработка.
    – Наращиваем большую ссылочную массу посредством вирусных ссылок.
    – Все поисковые системы моментально обращают внимание на наши применяемые базы.
    – Все размещенные тексты на интернет-сайте спамятся, они становятся неуникальными.
    – У нас очень большие возможности и практический опыт в данной сфере деятельности.

    Цена 50$
    Полная отчётность.
    Оплата: Киви, Yandex.Money, Bitcoin, Visa, MasterCard…
    Телега: @exrumer
    Whatssap: +7 906 531-21-55
    Viber: +7(977)5255462

  6. Kennethphish

    жесткое порно

    [url=]жесток порно видео[/url]

  7. Like!! I blog frequently and I really thank you for your content. The article has truly peaked my interest.

  8. Nikolldn

    Добрый день господа
    Наша предприятие мы занимаем первое место по качеству и цене производства аква продукции в Харькове. Вас может заинтерсовать:
    [url=–d/view?usp=sharing]Водопады по стеклу[/url] – сделаете Ваше помещение уютнее и привлекательнее, создаст теплую релаксирующую обстановку.–d/view?usp=sharing – узнать подробнее здесь.

  9. JamesHap

    перевод с мобильного на банковскую карту

    [url=]Мобильные деньги[/url]

  10. view it now

    I’m really impressed with your writing skills as well as with the layout on your weblog. Is this a paid theme or did you customize it yourself? Anyway keep up the excellent quality writing, it’s rare to see a great blog like this one nowadays.

    1. Sen

      Thank you for your feedback.
      It is free version theme.

  11. g

    Hello, I think your blog might be having browser compatibility issues.
    When I look at your blog site in Opera, it looks fine but when opening in Internet Explorer, it has some overlapping.
    I just wanted to give you a quick heads up! Other then that,
    fantastic blog!

  12. g

    Hello there! Do you know if they make any plugins to help with Search Engine Optimization? I’m trying to get my blog to rank for some targeted keywords but
    I’m not seeing very good results. If you know of any please share.

  13. g

    Wow! This blog looks just like my old one! It’s on a entirely different subject but it
    has pretty much the same layout and design. Superb choice of colors!

  14. g

    Hi my family member! I wish to say that this
    article is awesome, nice written and come with almost all vital infos.
    I’d like to look more posts like this .

  15. books

    The Great Alone New York Times Best Sellers The Count
    Of Monte Cristo Chapters

    My blog post … books

  16. Fatimah Sherraden

    ➡️ Digital Focus Marketing, 2a Botanic Grove, Edge Hill, Liverpool L7 5QH, 07398 137701

  17. books

    Latest Science News In The Philippines Psychology Books First Year

  18. KruteamTar

    Друзья, щедро делюсь с вами информацией. Нашла тут

    Мощную биржу фриланс-услуг со встроенным автоматизированным маркетом покупки-продажи цифровых товаров. Это уникальный проекте, на котором можно оказывать фриланс услуги, покупать и продавать цифровые товары, готовые, действующие проекты… Огромный функционал, множество автоматизированных функций, правильный многозадачный рейтинг… Администрация проекта выступает гарантом сделки между продавцов (исполнителем) и покупателем (заказчиком).

    Я думаю получить такую рекламу сразу всего за 5 рублей в сутки хороший вариант. Да это ротатор, но метрика стала показывать заходы с этого сервиса и некоторые длятся почти два часа с четырьмя зелеными кружками, раньше такого не было.

    Лучшие условия и самая низкая комиссия

    Если что не так, не судите строго, посоветуйте, может я не права?


  19. pdf

    Philip Pullman Goodreads Best Philosophy Books On God

    Also visit my blog – pdf

  20. pdf

    Phi Kappa Literary Society Uga Michael Pollan Amazon

    My web page :: pdf

  21. Having read this I thought it was extremely informative. I appreciate you taking the time and energy to put this informative article together. I once again find myself spending a lot of time both reading and leaving comments. But so what, it was still worth it!

  22. 10icdTar

    The updated ICD-10 2020 year – International Classification of Diseases provides assistance in the organization of health care and regulates the general rules of medicine. Unification of pathologies is necessary for system workers to designate a disease code. This simplifies the maintenance of statistics both inside clinics and in the state. It is also more convenient to keep track of the documentation and sort it into electronic data. For the first time the regulatory document was approved in 1893, and since then it has been repeatedly revised and updated with new clarifying data.

    ICD 10 was adopted in 2007, when the tenth revision of the World Health Organization was conducted. New rules allowed not only to classify, but also to encode medical diagnoses. Total list includes 21 sections (class), each of which is divided into headings. They contain codes of medical pathologies (diseases and conditions).

    Numbers are denoted by a letter of the Latin alphabet from A to Z and two digits after. The letters D and H are used for several diagnoses in different classes. U symbol left in reserve. Blocks of rubrics in a class describe diseases that are conditionally considered homogeneous. The block is divided into three-digit headings, which may contain subheadings with four-digit designation.

    [url=]icd 10 codes[/url]

  23. RussellGax

    [b]Комментарий одобрен[/b]

    Sol регистрация
    [url=]Плей Фортуна казино[/url]

  24. useful reference

    At this time it looks like Expression Engine is the preferred blogging platform out there right now. (from what I’ve read) Is that what you’re using on your blog?

  25. TuTuAviaTar

    Дешевые авиабилеты из Москвы в Симферополь.
    Введите даты и количество человек! А агрегатор поможет найти самое лучшее предложение для Вашего полета!

    [url=https://xn—-8sbah4a8cahb.xn--p1ai/aviabileti-moskva-simferopol.html]Авиабилеты Москва Симферополь[/url]

  26. Miss Date Doctor

    Really appreciate you sharing this blog article.Much thanks again. Really Cool.

Leave a Reply