Does It Fit? MCB Size Comparison

Does It Fit? MCB Size Comparison

This guide is to help you compare electrical circuit breakers with one another. It’s the MCB Size Comparison Site!

When I have been urgently needing some old obsolete breaker to ensure that a business can remain running, I struggled to find a reliable source of information with regards MCB fitments.

WARNING: This list is intended as a guide to enable qualified electricians to be able to make termporary repairs until such difficult to obtain circuit breakers can be obtained. IT IS NOT intended as DIY advice and should never be used by DIYers or the general public!

When replacing a circuit breaker with one which is not the same fitment as the original, ensure that the circuit breaker is replaced AS SOON AS POSSIBLE with the correct fitment circuit breaker.

This guide is to help you compare electrical circuit breakers with one another. When I have been urgently needing some old obsolete breaker to ensure that a business can remain running, I struggled to find a reliable source of information with regards MCB fitments.

How Does MCB Size Comparison Work?

In the list below you will find a number of Electrical Switchgear Manufacturers. If you click the link, you will be guided to the relevant page with the information about that manufacturer.

A list of part numbers will show for that particular manufacturer. In order to be able to ensure accurate MCB size comparison, there are pictures of the relevant circuit breakers so you can be sure you have found the correct list.

That particular page will then list the part numbers of any MCBs/RCDs which we know are a cross match with the original part. Again, it should be said that if any recommendation is made that a part fits, this is purely down to measurement of the sizes and is FOR TEMPORARY REPAIRS/EMERGENCIES ONLY and a suitable original part circuit breaker should be sourced to replace it.

If no original equipment replacement exists, then upgrading to modern equipment may be needed. It is not a sensible idea to run the installation with cross-branded circuit breakers in the consumer unit/distribution board.

Although they might fit, there has been no type testing by the manufacturer to ensure that the different makes/models are compatible with each other. Whilst yes they all meet an agreed standard, there are slight differences in each manufacturers product. Different heat outputs, etc…

Not only that, but the requirement in the 18th edition is that all switchgear equipment is to suitable according to manufacturers literature. This means that it must be a single make/model enclosure and associated switchgear.

Manufacturer Names:

Click on the relevant manufacturer name below to be taken to the page detailing further information about the MCB size comparison information you need.

  • WYLEX
  • EATON MEM (MEMSHIELD)
  • MK
  • BRITISH GENERAL
  • CONTACTUM
  • CRABTREE
  • HAGER
  • SQUARE D
  • SCHNEIDER

Where To Source Replacement Breakers?

You need to know a good source of replacement circuit breakers if you are doing any type of electrical maintenance works which will require you to deal with this type of repair.

Older circuit breakers & boards are still fitted to thousands of homes and businesses in the UK and will continue to be used for years to come.

MCB Size Comparison

If a customer needs a board repairing with a new circuit breaker or RCD, you need to know that you can source a replacement in a good timeframe and from a trusted source. Here are the people we have used before and found to be both reliable and keenly priced.

Not only that, but they are really helpful when trying to source different parts and you need advice. All circuit breakers/RCDs are cleaned and tested before resale. The sellers listed below are qualified electricians not just bedroom traders, so you can trust the advice you are getting. These companies may also be able to help provide advice which helps with MCB size comparison

Wentvale Electrical

Based in Knottingley, Wesr Yorkshire, provides a prompt and reliable UK next day delivery service with Royal Mail. Holds vast stock at a great price, and can help you find that part you so urgently need.

Willrose Electrical

Great website listing a huge number of circuit breakers and RCDs which they hold in stock. Fast deliery and very keen pricing. Based in Devon delivering nationwide.

Circuit Breakers Online

Large website listing many rare and obsolete circuit breakers for sale. Next day delivery on items ordered before 2pm (Mon-Fri) by Royal Mail means these can help you out if you are stuck needing a part fast.

It is worth noting that most of these sellers will also buy collections of circuit breakers from you so if you are taking them out on board changes then you should really be keeping them as some are worth some serious money!