What do folk do when given a CU with switch on wrong side?

[Davisonp]

I came across this earlier this week doing an EICR and would value your opinions on this matter.

I have occasionally been given a CU to install only to arrive and find the switch is on the wrong side of the CU and it will not fit in the current configuration. I was taught to move the switch and RCD positions, switch live and neutral inputs and outputs on the main switch and RCD’s meaning the live feed out of switches and RCD’s is directly next to any MCB’s. (hope this makes sense)

Is that good practice? What do others do?


This is what I found earlier this week. Note the live and neutral into the RCD and consider the busbar feeding the MCB’s.

See photo

The installer got round the issue of the neutral output from the RCD’s being between the live output and the MCBs by taking the Busbar from the live output, cutting of the tab that would have gone into the neutral output and then onto the MCB’s. I consider this incredibly dangerous. If you consider the neutral stranded cables out of the RCD is now crushed by the busbar and plastic cover that will not seat fully because it is interfered with by the protruding neutral cable.

See second Photo

Both the live and neutral outputs of the RCD are only protected by the 100A service fuse. In the event of a fault causing heat, there could be a huge bang if the plastic separating the neutral from the busbar melts.

 

[Wilko]

Sharp intake of breath here at seeing pic #2 ...

 

[Andy78]

How can the main switch be on the wrong side if it is supplied by the manufacturer in that configuration ?

 

[streamer]

I think I would have put new mains tails in.

 

[Wilko]

I took it that Mr Spark dismantled CU and reversed the order because the tails came in at other end and weren't long enough. I'm with Streamer

 

[stevethesparks]

I generally fit either BG or MK as they have the main switch at opposite ends, but then I always visit site first. Whoever is giving you CU's to fit, you need to bring it up with them as to why they haven't made an allowance for the switch position or new tails.

 

[SparkyChick]

I fitted a new MK Sentry board at home and it was configured the wrong way, so I disassembled it and reassembled it so it would work, ensuring none of the internal cables were under undue strain. I certainly wouldn't do what's shown in pic #2 as that does appear to be a disaster waiting to happen.

Fitting new tails wasn't really an option because they are in the cavity and I didn't want the headache of opening a new cable exit point in the wall or chasing the wall out to accommodate them as there were already cables in the wall.

I don't see a problem with tweaking the layout of the board, it's just like buying an empty board and filling it yourself.

 

[Octopus]

Henley block and extend tails is a far easier solution

 

[onions1066]

That is rubbish, lazy and dangerous. But I would love to see the bang

 

[Davisonp]

How can the main switch be on the wrong side if it is supplied by the manufacturer in that configuration ?

Old CU has switch and tails in on right and new CU has switch on left but meter tails cannot be moved.

 

[Davisonp]

I generally fit either BG or MK as they have the main switch at opposite ends, but then I always visit site first. Whoever is giving you CU's to fit, you need to bring it up with them as to why they haven't made an allowance for the switch position or new tails.

I also fit a CU with the switch at the correct side.

 

[Davisonp]

I think I would have put new mains tails in.

The example I had when gaining experience was an SWA feed through a wall to a sub board that we were changing, so not practical to extend tails.

I do make sure I have the right CU for replacement, but is switching things around and making sure the live output is in the correct position for Bus Bars considered acceptable or should the CU be taken back and changed it for a more suitable one?

 

[Davisonp]

Henley block and extend tails is a far easier solution

In this case, a Henley block would have meant repositioning the CU and extending all circuits, so not practical.

Replacing tails would have meant tails come in on the left, and run the entire length of the CU to the switch on the right. I would not be comfortable with that if it were my job.

 

[Octopus]

Pre metal cu's I used to fit Wylex, or sector cu's ..... Basically the same product the main difference being which end the main switch was.....

 

[westward10]

I would never reconfigure a board get one to suit your purpose.

 

[Leesparkykent]

Sharp intake of breath here at seeing pic #2 ...

because the boards built in spirit level is showing it's been put up wonky?

 

[davesparks]

Old CU has switch and tails in on right and new CU has switch on left but meter tails cannot be moved.

So use a CU which has the main switch on the right.

Messing around with the configuration is unnecessary and probably goes against manufacturers instructions.

 

[davesparks]

In this case, a Henley block would have meant repositioning the CU and extending all circuits, so not practical.

Replacing tails would have meant tails come in on the left, and run the entire length of the CU to the switch on the right. I would not be comfortable with that if it were my job.

Why would you not be comfortable with that?

 

[Ian1981]

It's strange because I fit hager all the time and the main switch is always right hand side even the plastic dbs where or have I clearly missed the point and the db has been reconstructed the other way by someone?
Only db I've used which is opposite is mk sentry and Crabtree

 

[HandySparks]

... or have I clearly missed the point and the db has been reconstructed the other way by someone?

Yes, but badly.