Overloaded Consumer Units

[securespark]

This I saw today. The Ivory unit has 60A main switch. Diversified load well over that.
Metalclad unit has 45A main switch. Those ARE 2 40A shower breakers you can see.

How would you re-arrange this lot?

 

[Steve]

Thats a shame - someone's actually made the effort to make it look good!

The two shower breakers could be put straight into a 2-way enclosure with RCD.

The rest of the install into a split load board? Is it a trick Q?

Why were you called out to this?

 

[securespark]

Not a trick question. Just wondered how others would tackle it, that's all.

Called out for a lighting fault, but have to do quick inspection while I'm there.

 

[plugwash]

A couple of holes in craftys soloution

firstly be carefull when selecting the two way box, two way RCD only units don't tend to be supplied with 80A RCDs.

secondly space is going to be a problem, i doubt you'd get a suitablly big split load in there.

 

[Steve]

If the customer wants the electrics keeping in this box, I'd probably loose the henley block, feed one CU straight from the meter, then feed the other CU from the load side of the main isolator.

You could have one or both CUs split load, or one RCD and the other not.

Or would one of those 2-level CUs fit here?

Use a metaclad CU to terminate that cable on the RHS to.

 

[securespark]

I've had a think...Do your diversity calcs on the main board, then add in two 40A+ showers. I think it's too much. The showers need to be interlocked.

 

[ricicle]

. The showers need to be interlocked.

Or put them on the same MCB..............................

 

[nozspark]

Here's another one, with other probs aswell.
Note this CU is fed off a 60A BS88

 

[ricicle]

Why are some of the phases identified with blue and some with G/Y tape....

 

[securespark]

Just markers: I do it but take mine off.

"Blue tape 2.5 immersion heater.

Black tape 2.5 CH

etc........"

 

[ricicle]

Just markers: I do it but take mine off.

"Blue tape 2.5 immersion heater.

Black tape 2.5 CH

etc........"

You must have forgot on that one...........

 

[nozspark]

Yeh, no identification of circuits, about 10x 32A circuits, 2 x elec showers, only things on RCD is top right rail, 1.0mm T&E radial circuits into 32A MCB's,,,,,,the list goes on

And all fed off a 60A BS88

 

[DavePrior]

If the customer wants the electrics keeping in this box, I'd probably loose the henley block, feed one CU straight from the meter, then feed the other CU from the load side of the main isolator.

Apologies for hijacking the thread
Crafty, help this beginner out please - how is this done?

 

[ColJack]

60A main fuse then just put in a 63A breaker to feed the second unit and a neutral of suitable size to link the neutral bars..

 

[Steve]

60A main fuse then just put in a 63A breaker to feed the second unit and a neutral of suitable size to link the neutral bars..

My idea was to do as in Secure's picture - with the second CU fed from the LOAD side of the main isolator. Thus providing a second CU, while maintaining a single point of isolation. 63A MCBs are not available for all boards.