MCBs

MCBs from Hager, ABB and Wylex

Choosing curve and rating

Miniature circuit breakers protect a circuit against overload and short circuit. The curve tells you how the breaker handles inrush. Type B suits most domestic and general lighting and power circuits, Type C is for loads with higher inrush such as some motors and lighting banks, and Type D covers heavier inductive loads. Match the rating to the cable and the load, and match the brand to the board. Getting the curve right avoids nuisance tripping on start up and gives the right level of protection for the cable.

Single and triple pole

Most domestic boards use single pole MCBs, while three phase commercial boards need triple pole devices. Our range includes the ABB S201M and S203M ranges in a spread of ratings, Hager MTN single pole breakers and Wylex devices. Because breakers are designed for specific boards, check compatibility with the board you are working on before ordering. Mixing brands in a board is not a good idea, so stick with the manufacturer of the board you are working on. If you are not sure which range a board belongs to, a photo of the label usually tells you.

The rating you need, in stock

Nothing stalls a board change like being one breaker short. This page shows live stock from the Moss Electrical counter in Bridgend, where we have supplied switchgear to electricians since 1992. If the rating you need is not listed, call 01656 765300. Many electricians keep a few common ratings in the van for call outs, and it is worth checking stock before a full board change too. The counter can also help match a breaker to an older board that is no longer easy to identify. Bring a photo of the existing breakers to make it quicker.