Replacing wylex mcb

'usually' there is a spring loaded clip holding the MCB to the rail

. With the main switch off, have a look at the top of the MCB for a little metal clip. Lift this with a screwdriver and the MCB should move forwards at the top end allowing you to lift it up and out of the CU. I am sure some older CUs had MCBs that had a clip at the bottom so look at both ends.

-- Adam

adamwadsworth@(REMOVETHIS)blueyonder.co.uk

The latest NH Wylex CUs don't use the bottom spring clip. They hook over the top rails and are held in by the screw to the busbar. As this is peculiar to Wylex it seems you have to replace with Wylex mcb not another make

Makes wonder why they adopted the DIN rail as a method of attachment

Errrr - to FORCE you to use their MCBs perhaps ????

Nick

Their mcbs are DIN rail compatible. However, they seem to have an extra connection slot in front of the DIN rail one. This fits their busbar and holds the mcb in. It is a very convenient arrangement. I looked at MK mcbs in a store and they don't appear to have this extra slot so wouldn't probably fit the Wylex busbar. I may be wrong of course.. I don't know the din standard details, but does it actually say anything about how the busbar should be arranged? Every manufacturer may be able to do their own thing..

The busbar connections still seem to vary significantly between manufacturers. What has improved over the last 10 years or so is the distance from the DIN rail to the front face and the size of the front face opening has become more standard than it once was.