Thoughts on moving an existing CU

[littlespark]

Local funeral place is getting a new mortuary fridge unit, and needs some work done.

The CU, just for the room, is high up in the corner, just above the fridge unit. Stupid place to have it, as you need to crawl over the top of the unit to get to it. 2 foot of crawl space, and my dodgy knee. Great.

Board just needs moved along the wall to above the door, everything in surface pvc trunking on wet wall panelling. No trouble extending circuits.
No room elsewhere to put it. Walls are lined with cabinets and other equipment. Above the door is an improvement, just not an ideal working height.

From what I can see, it’s an old Merlin Gerin board, no rcd.

Ideally, would change the board to all RCBO… but I can’t even tell how many circuits are off this board.
Going in on Saturday to PAT their equipment… so I’ll get up on the fridge for a better look.

 

[brianmoooore]

There's a liability issue to consider. Someone up on a chair, resetting something on the CU. Someone charges through the door, All go flying. Injuries are incurred. Who fitted that CU in such a stupid place, contrary to recommendations?

 

[Spoon]

There's a liability issue to consider. Someone up on a chair, resetting something on the CU. Someone charges through the door, All go flying. Injuries are incurred. Who fitted that CU in such a stupid place, contrary to recommendations?

Just make sure the door is open when messing with the CU.. Job done.

 

[OnlQQker]

It's posts like this that inspire my horror movie writing,
I guess at some stage the existing freezer will be off for a bit? That's ok for a few hours as long as nobody opens the fridge door and things start defrosting.

Where are the tails coming in to the existing CU, could you tap into these and add another twin CU?

 

[littlespark]

The supply is from a 32A mcb in the main board, so suspect 4 or 6mm t&e.. might be SWA.

I did ask what happens to the fridges with the power off for a time…

“Just keep the doors shut. Be alright”

Ok, so just like a domestic fridge freezer, then.

 

[telectrix]

why not find a suitable location outside of the room especially as the walls in the room are wet.?

 

[littlespark]

why not find a suitable location outside of the room especially as the walls in the room are wet.?

I did think of this, Tel.
Back to back is the chapel of rest room… (where the door goes) and there’s nothing on the wall.

Could leave it in a corner, but bring it down to a manageable height.


I don’t really know how “wet” the room gets. Nothing is IP rated, no drains on the floor or anything.
I think it’s just been wet wall panelled for ease of cleaning.

 

[davesparks]

why not find a suitable location outside of the room especially as the walls in the room are wet.?

The wall isn't wet, it's clad with waterproof panelling.

 

[OnlQQker]

Wet walls and electricity, crossed with mortuary fridge units and defrosting freezers, makes me wonder if something like this was behind the ideas for the writer of the book Frankenstein.


Mind you if you want to see walking dead people, you only have go shopping for the day in Central Milton Keynes!

 

[littlespark]

Wet walls and electricity, crossed with mortuary fridge units and defrosting freezers, makes me wonder if something like this was behind the ideas for the writer of the book Frankenstein.


Mind you if you want to see walking dead people, you only have go shopping for the day in Central Milton Keynes!

I will not be doing this work in the middle of a lightning storm…

“It’s aliiiiiive!”

 

[pc1966]

I will not be doing this work in the middle of a lightning storm…

“It’s aliiiiiive!”

Not the third switch!

 

[pc1966]

Who fitted that CU in such a stupid place, contrary to recommendations?

So, so, SO many people

My own flat has the CU about 8 feet above the ground, just as you come in the door. It did cross my mind to move it, but a massive job as few other places that are actually more sane near there, and it would also really mean getting the DNO to move the cutout/meter which is also there, or me to fins some means of getting SWA to another place. Opposite side and lower was obvious choice, but fitted wardrobe in bedroom. Sigh.

 

[littlespark]

I think the room had been wired before they thought about where the fridge was going.
Maybe the original unit was only one door, 3 drawers… and they’ve upgraded to twice the size, hence blocking access to the board.

Now they’re upgrading again… slightly larger unit. No more capacity, but around 8 inches wider… more insulation maybe??

The old unit is going up to their other premises. A garage where they keep the limos and 200 odd coffins.

 

[littlespark]

I’m moving the light at some point as well..

Switch is getting blanked off, new fridge is wider and will cover. Hoping I can pull cables up into that trunking to joint. (In a box, not joint in trunking)
Still a working switch at other door.
Wall is brick, so putting things on other side of wall could be messy.

 

[davesparks]

How much time is there between the old unit being removed and the new one being installed?

Or how much time can you negotiate for?

 

[pc1966]

I’m moving the light at some point as well..

Presumably new LED one?

Switch is getting blanked off, new fridge is wider and will cover. Hoping I can pull cables up into that trunking to joint. (In a box, not joint in trunking)
Still a working switch at other door.

I wondered about that, if going for a movement sensor in the light rather than switch?

I am presuming it is not going to have the 'clients' walking about at night...

Wall is brick, so putting things on other side of wall could be messy.

True, though a masonry/diamond hole saw would allow a neat 2-3" hole to be cut for cables to go therough and you could have trunking running down on the other side to the CU.

 

[littlespark]

Don’t want to damage the decor on other side of wall, it’s the Chapel of Rest.

Crawled over the fridge and took cover off.

I can see now the wet wall cut around this… so I’ll repurpose as a joint box and run extensions along the 2x2 below.

 

[brianmoooore]

An 'inverted' CU, I see.
...

 

[littlespark]

An 'inverted' CU, I see.
...

I think the Merlin’s are like that.

Speaking to the director and seems the new fridge is taller too..
so it’s going to be a hassle whatever I do.

 

[davesparks]

An 'inverted' CU, I see.
...

It's the right way up?

 

[Penguin]

I’m moving the light at some point as well..

Switch is getting blanked off, new fridge is wider and will cover. Hoping I can pull cables up into that trunking to joint. (In a box, not joint in trunking)
Still a working switch at other door.
Wall is brick, so putting things on other side of wall could be messy.


View attachment 108540

First of all find out who fitted the ISO and modules Up Side Down. C2 incorrect install etc.

Is the non-diffuser flori unit the only light source.?? If so you could identify and isolate this radial at the DB and run new within the trunking using metal ties and run in conduit fixed to ceiling via PIR sensor to a 5’ LED IP unit. I say IP as it looks like an industrial chilling area.

 

[nicebutdim]

First of all find out who fitted the ISO and modules Up Side Down. C2 incorrect install etc.

Only ever seen a couple of Merlin Gerin single phase boards, but pretty sure they're intended to be installed this way (as per 3 phase boards). Those I've seen even had the same isolating busbar used on their 3 phase boards.

 

[Penguin]

I think the room had been wired before they thought about where the fridge was going.
Maybe the original unit was only one door, 3 drawers… and they’ve upgraded to twice the size, hence blocking access to the board.

Now they’re upgrading again… slightly larger unit. No more capacity, but around 8 inches wider… more insulation maybe??

The old unit is going up to their other premises. A garage where they keep the limos and 200 odd coffins.

Please show us that photo of the DB again.
And remember the ‘working in confined spaces’ H&E1972.

Can’t you organise with the client to do the job once they’ve removed the old unit. Gives you good access then, and run a temporary feed to the new unit placed elsewhere in the room.
I bet your dying to start this job.

 

[littlespark]

Thanks for all the replies.

The room wasn’t planned well in the first place, but any fridge unit has to be located here so that there’s room in front for the trolley.

There’s 2 light fittings. He just wants this one spun round as it’s lighting up the top of the unit.
Will change to IP if asked for.

It’s not really classed as a “wet” room, but it just makes it easy to clean the walls.

There is a void down right hand side, due to a floor level pipe box, so might just need to use a few WAGO boxes to extend the circuits, although some are surface trunking and could be easily rewired.

The switch is going to be the problem, as the cables are chased into the brick wall behind the wet wall… and a joint made in this switch would be blocked by the new unit.
I suppose if I use WAGOs, they should be MF.
If there’s a feed at the light, then occupancy sensor or quinetic could be a good shout. I could disconnect the switches entirely.


There must be some point where the fridges aren’t getting used.
They must be made up in situ from panels and all bolted together, which will take some time.
The occupants can’t just be left on the trolley or anything.

 

[Penguin]

Thanks for all the replies.

The room wasn’t planned well in the first place, but any fridge unit has to be located here so that there’s room in front for the trolley.

There’s 2 light fittings. He just wants this one spun round as it’s lighting up the top of the unit.
Will change to IP if asked for.

It’s not really classed as a “wet” room, but it just makes it easy to clean the walls.

There is a void down right hand side, due to a floor level pipe box, so might just need to use a few WAGO boxes to extend the circuits, although some are surface trunking and could be easily rewired.

The switch is going to be the problem, as the cables are chased into the brick wall behind the wet wall… and a joint made in this switch would be blocked by the new unit.
I suppose if I use WAGOs, they should be MF.
If there’s a feed at the light, then occupancy sensor or quinetic could be a good shout. I could disconnect the switches entirely.


There must be some point where the fridges aren’t getting used.
They must be made up in situ from panels and all bolted together, which will take some time.
The occupants can’t just be left on the trolley or anything.

I’m presuming that you’ve made your ADMD calculations and know the electrical demand required for this new bigger body fridge unit?
Also the minute you start work YOU become responsible for the circuits and their protection, so RCBO/RCD are a must.

I also include at the design stage an IP EM to assist in the event of a light circuit failure or power cut.

 

[westward10]

I’m presuming that you’ve made your ADMD calculations and know the electrical demand required for this new bigger body fridge unit?
Also the minute you start work YOU become responsible for the circuits and their protection, so RCBO/RCD are a must.

I also include at the design stage an IP EM to assist in the event of a light circuit failure or power cut.

RCBO/RCD is not necessarily a must.

 

[Penguin]

RCBO/RCD is not necessarily a must.

I know we can only speculate the job in hand from the info supplied, but when I here that they’ve got wet walls, Non IP light fittings/trunking/ finger operated light and fridge ISO switches, not forgetting a large metal fridge unit, why would you not consider Residual Current protection.??
(Taking into account the spike start of a refrigerator unit). Please advise.

 

[westward10]

Installation methods will often dictate if RCD protection is required for all circuits, I often avoid it where possible.

 

[Penguin]

Installation methods will often dictate if RCD protection is required for all circuits, I often avoid it where possible.

Absolutely, the Data plate and Install will show the way..!!
But as the lengthy accident report made reference in this report to the Beko fridge failures causing that horrendous fire, and highlighting that there wasn’t any residual imbalance protection installed, (which may have reconsidered any immediate fault), the disaster may have been avoided.
I know there were other issues as well.

We attended, following a garage block fire where a fridge freezer on a B16 caused the fire. The fire brigade report stated that the DB socket feed was still live after the fire was dealt with.

Safety first.

 

[littlespark]

As can be seen from the earlier photos, the circuits are not RCD protected, but i know the sockets on the end of the circuits are. (BS7288)
Lighting is not, granted.
I wouldn't want the fridge unit itself tripping out unnecessarily, but noted about the data plate. Im only assuming it requires the same power supply, as the director said it was the same size. I should check that myself.

 

[Penguin]

Only ever seen a couple of Merlin Gerin single phase boards, but pretty sure they're intended to be installed this way (as per 3 phase boards). Those I've seen even had the same isolating busbar used on their 3 phase boards.

Only ever seen a couple of Merlin Gerin single phase boards, but pretty sure they're intended to be installed this way (as per 3 phase boards). Those I've seen even had the same isolating busbar used on their 3 phase boards.

Your spot on with that Merlin Unit.!

Old Chinese Proverb…. But glasses on when viewing photos before commenting.

What with the cover lid hinged downwards and a top mounted Busbar..etc

Learning has taken place, Thankyou.

 

[Penguin]

As can be seen from the earlier photos, the circuits are not RCD protected, but i know the sockets on the end of the circuits are. (BS7288)
Lighting is not, granted.
I wouldn't want the fridge unit itself tripping out unnecessarily, but noted about the data plate. Im only assuming it requires the same power supply, as the director said it was the same size. I should check that myself.

You said earlier it was a bigger unit?

 

[littlespark]

You said earlier it was a bigger unit?

physically bigger... as in slightly wider and slightly taller.... Not like its going from 8 drawers to 12 or anything.

I'm not envisaging the power requirements to be any bigger... but i will check.

 

[pc1966]

I wouldn't want the fridge unit itself tripping out unnecessarily, but noted about the data plate. Im only assuming it requires the same power supply, as the director said it was the same size. I should check that myself.

Good point about the RCD and risk of spurious power failure. Schneider used to do RCBO with "super immune" (probably very short delay) on 30mA protection like this:

A9DF3632 - residual current breaker with overcurrent protection (RCBO), Acti9 iCV40, 1P+N, 32 A, C Curve, 6000 A, 30 mA, A-SI type | Schneider Electric UK

A9DF3632 - residual current breaker with overcurrent protection (RCBO), Acti9 iCV40, 1P+N, 32 A, C Curve, 6000 A, 30 mA, A-SI type

www.se.com

But I see that has been discontinued.

It might be worth checking the MI if RCD is needed and if it could be hard-wired FCU and cables in SWA or Flexishield, etc, to allow MCB-only protection.