Commercial CU change - legalities etc.

MFS Electrical · May 6, 2018

123 said:
This seems like another how to over complicate everything that should be simple thread

Or how to simplify over complicated things, nah you were right the first time

The Ghost · May 6, 2018

Anyway I know that's a trick question.

westward10 · May 6, 2018

Andy78 said:
One that conforms to BS EN 60947-2 and has a higher rating in terms of breaking capacity ?

So an mccb then?

westward10 · May 6, 2018

Vortigern said:
An MCB rated as stated at 10Ka are generally used more in a commercial situation and if you ask at a wholesalers for an MCB for domestic purposes you will normally be offered a 6Ka rated MCB.
Miniature Circuit Breakers (MCB) guide | Newey & Eyre - http://www.neweyandeyre.co.uk/guide-to/miniature-circuit-breakers
say;
i.e. An MCB’s circuit rating is given in Kiloamps (KA), and this indicates the level of its ability to work. For example a domestic MCB would normally have a 6KA fault level, whereas one used in an industrial application may need a unit with a 10KA fault capability.

I would never ask a wholesaler what protective device I should use for a particular application.

Andy78 · May 6, 2018

westward10 said:
So an mccb then?

No. BS EN 60947-2 also covers standard mcbs for use within commercial and industrial environments. Most manufacturer's ranges of 10kA and upwards will be to this standard.

davesparks · May 7, 2018

westward10 said:
What exactly is a commercial mcb?

There are two standards for MCBs, 60898 covers MCBs for domestic and similar applications and 60947 covers other applications.
Generally a 60898 mcb will have a 6kA rating and won’t necessarily comply with 60947, whereas a 60847 mcb will generally have a 10kA+ rating and will be ‘dual rated’ to 60898 also