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.

 

[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.

 

[HandySparks]

I can't remember doing it myself, but I can't see a problem with it, if done properly. Anyone have any technical reason for not reversing the order of a board?

 

[Ian1981]

I suppose if reconfigured then may not be covered by manufacturers warranty and can't be guaranteed by them as it's been messed with

 

[stevethesparks]

I can't remember doing it myself, but I can't see a problem with it, if done properly. Anyone have any technical reason for not reversing the order of a board?

If the main switch is situated at the opposite end, you will have to supply the LN terminals with the wrong polarity to allow the bus-bar to come off the correct side, of which might also make the L last to break first to make in some cases.

 

[Davisonp]

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

Yes in the actual situation I came across this week (not the hypothetical one which I came up with which is the opposite) the tails come in on the left in a corner, and Hagar have switch on the right.

 

[Davisonp]

Why would you not be comfortable with that?

I would be fine with that if I have been provided with the recourses and time to do that by the boss, and of course if there is space to move the board.

 

[telectrix]

turn the bugger upside down. then say a builder did it.

 

[PEG]

turn the bugger upside down. then say a builder did it.

I have seen this (almost) many times,not upside down as such,but 90 degrees out...and one in a large Victorian vestibule,which was mounted on the ceiling,with all switches pointing at the floor

 

[Davisonp]

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.

I agree entirely, and I have never provided an incorrect CU for installation myself, but look at it from another prospective. If you had sourced the wrong CU and then told someone who works for you to adjust it and fit it and the work is covered by your company insurance, would they? or would they refuse?
There are some things I have been told to do as a sub contractor that I have refused as it causes danger or specifically goes against the regs, but there are things that I have been told to do under the responsibility of the parent company that I have done as instructed.

 

[HandySparks]

... which might also make the L last to break first to make in some cases.

It might. Anyone know if these double pole switches are actually constructed this way, ie with one pole making before the other?

 

[telectrix]

the only way i could get a 10 way split CU in the space available at home was to mount it sideways on. it's a plastic CU and it's been in there for 6 years without catching fire or nuisance tripping . a 3 phase board has all the breakers horizontal anyway.