Keep or Remove

[wreck-it-steve]

We had our 3 phase distribution board change a few months ago from a 18 way cartridge fuse type board to a 24 way mcb board. There was no main isolator on the old boars but it had a 100a mem switch fuse mounted under it that presumably provided the isolation. .


The new board does however have a 125a isolator so wanted to know if I could get the mem switch fuse removed as it's taking up space. Or is it still required.

The supply to the switch fuse comes from tails connected to the service head less than half a meter away.

Thanks

 

[Lectrician]

Yes, assuming the head us a standard 100amp type, ie, not larger than your 125amp incomer.

 

[Taylortwocities]

Why is a switch fuse required? How far away is the consumer unit from the switch/fuse? A picture or two might help.

 

[Lectrician]

The switch fuse was more than likely bushed to the bottom of the old fusebox. That's how they used to be fitted.

 

[Taylortwocities]

He said that

The supply to the switch fuse comes from tails connected to the service head less than half a meter away.

But the dist board may be many meters away from that. Need more info, me thinks..

 

[JohnW2]

He said that

The supply to the switch fuse comes from tails connected to the service head less than half a meter away.

But the dist board may be many meters away from that. Need more info, me thinks..

I suppose it could be 'many metres away', if the room were many meters high (and the board many metres from floor level), but that all seems pretty unlikely! ... the OP said:

...There was no main isolator on the old boars but it had a 100a mem switch fuse mounted under it that presumably provided the isolation.

Kind Regards, John

 

[wreck-it-steve]

Thanks for all your replies. the switch fuse was bushed to the bottom of the old board and has fuse wire in it. the service head is less than half a meter to the side of the DB.

 

[ban-all-sheds]

But the dist board may be many meters away from that.

"Many"?

Usually only 1, or sometimes 2 for dual-rate tariffs. Might you get 3 with a 3-phase supply? Would that qualify as "many"?

 

[Taylortwocities]

Bloomin spel chock. METREs, but ewe new tha didn ya