# What is the difference between 4 pole MCB and Triple pole and neutral?

**URL:** <https://forumautomation.com/t/what-is-the-difference-between-4-pole-mcb-and-triple-pole-and-neutral/10119>\
**Category:** Electrical\
**Tags:** switchgear\
**Created:** [January 12, 2022, 5:22am UTC](https://forumautomation.com/t/what-is-the-difference-between-4-pole-mcb-and-triple-pole-and-neutral/10119 "2022-01-12T05:22:08Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![instrumentationtechi](https://forumautomation.com/letter_avatar_proxy/v4/letter/i/50afbb/32.png) [@instrumentationtechi](https://forumautomation.com/u/instrumentationtechi)\
**Post date:** [January 12, 2022, 5:22am UTC](https://forumautomation.com/t/what-is-the-difference-between-4-pole-mcb-and-triple-pole-and-neutral/10119/1 "2022-01-12T05:22:08Z")

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**Explain how the 4 pole MCB is different from Triple pole and neutral?**

 ![1 - Copy](https://cdn.forumautomation.com/original/2X/e/efb197c00d6cfe9a768f75720f2ecaa7fe3a04f3.jpeg)

**Reference Image Provided by the Respondent**

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**Author:** ![ashlin](https://forumautomation.com/user_avatar/forumautomation.com/ashlin/32/3775_2.png) [@ashlin](https://forumautomation.com/u/ashlin)\
**Post date:** [January 12, 2022, 5:26am UTC](https://forumautomation.com/t/what-is-the-difference-between-4-pole-mcb-and-triple-pole-and-neutral/10119/2 "2022-01-12T05:26:19Z")

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TPN= Thripple pole + neutral. Three (Triple) contacts make and break but neutral is closed contact.

Whereas 4P (3 phases +Neutral) all 4 contacts make and break together.

TPN means Triple Pole(TP)+ Neutral(N)which is 3 phases and neutral, but the protection is given for three phases only and in 4 pole MCB protection is given to all 3 phases as well as neutral. In the case of 4 pole MCB, the purpose is not to protect the neutral but it is rather to isolate the neutral.

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**Author:** ![Rabert](https://forumautomation.com/user_avatar/forumautomation.com/rabert/32/6784_2.png) [@Rabert](https://forumautomation.com/u/Rabert)\
**Post date:** [July 17, 2026, 2:33am UTC](https://forumautomation.com/t/what-is-the-difference-between-4-pole-mcb-and-triple-pole-and-neutral/10119/3 "2026-07-17T02:33:39Z")

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## Why is 4-pole MCB used?

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**Author:** ![TSRS](https://forumautomation.com/user_avatar/forumautomation.com/tsrs/32/8023_2.png) [@TSRS](https://forumautomation.com/u/TSRS)\
**Post date:** [July 17, 2026, 2:40pm UTC](https://forumautomation.com/t/what-is-the-difference-between-4-pole-mcb-and-triple-pole-and-neutral/10119/4 "2026-07-17T14:40:01Z")

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In **[three-phase electrical systems,](https://forumelectrical.com/electrical-certificate-of-compliance-coc-and-electrical-safety-certificate/)** a **[4-pole MCB](https://forumelectrical.com/how-to-connect-a-3-phase-motor-with-solid-state-relay/)** is utilized to properly separate and safeguard the neutral wire as well as the three live phase conductors. It eliminates floating neutral dangers, regulates unbalanced loads, and guarantees complete circuit shutdown in maintenance (or) faults.

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**Author:** ![Rabert](https://forumautomation.com/user_avatar/forumautomation.com/rabert/32/6784_2.png) [@Rabert](https://forumautomation.com/u/Rabert)\
**Post date:** [August 3, 2026, 7:59am UTC](https://forumautomation.com/t/what-is-the-difference-between-4-pole-mcb-and-triple-pole-and-neutral/10119/5 "2026-08-03T07:59:04Z")

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> [@Rabert](#):
>
> 4-pole MCB

 ![1 - Copy](https://cdn.forumautomation.com/original/2X/e/efb197c00d6cfe9a768f75720f2ecaa7fe3a04f3.jpeg)