Need help with wire spec- Cold room

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Hi everyone,

I'm having a cold room being installed on Thursday (Spec sheet is attached).
They are coming to install the unit on Thursday 4th.

The wiring hasn't been done yet as I recently leased the place.

The unit need a 3 phase electricity. No electrician is free to do the routing so I will have to do it myself so electrician can come and connect the bits to power supply and end it with insulator.

My question is what sort of cable size , fuse, insulator other parts I need ? I also need a meter reader.

Some information:

Routing is indoor.
Length required: 40m

Power consumption 2566 W each phase.

Current consumption 4,3 A each phase.

Further info in PDF.

I guess the fuses will be installed in the grey box.


I really appreciate your help. My container is arriving on Saturday and I'm expecting 8 tonnes of freezer goods so need to have the freezer installed by then.


IMG_1683.jpg
 

Attachments

  • Rivacold FTL034Z002 (11).pdf
    383.5 KB · Views: 390
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How will the cable be routed from the board 'grey box' to the isolator 'insulator'? Clipped to the wall and uncovered? Buried in the ground? Routed through insulation? That will determine the current carrying capacity of the cable and therefore the size. The length of the run will also determine the cable size. The type of cable will determine the cable size also.

Are you actually going to connect this yourself?
 
I guess the fuses will be installed in the grey box.
I guess that they will not, seeing as it is a Federal Electric.
One good thing - fire extinguishers are on hand to deal with the inevitable.

As for the rest - 2.5mm 4 core SWA would probably do, a new board with suitable devices in it, glands, cable cleats, some sort of box at the other end, and so on.
This is not a topic for a DIY forum.
 
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I'm having a cold room being installed on Thursday (Spec sheet is attached).
You won't be, if you come to your senses, which you must do.



No electrician is free to do the routing so I will have to do it myself so electrician can come and connect the bits to power supply and end it with insulator.
This is clearly a place of work.

The EAWR apply, and equally clearly you do not have the legally required competence to be doing this work. (And FGS everyone here, please do not do anything to facilitate or encourage this guy to do this electrical work himself).

You MUST use an electrician.


My container is arriving on Saturday and I'm expecting 8 tonnes of freezer goods so need to have the freezer installed by then.
You can't, not legally.

You should have planned better.

You've got no choice but to delay the arrival of these goods.
 
How will the cable be routed from the board 'grey box' to the isolator 'insulator'? Clipped to the wall and uncovered? Buried in the ground? Routed through insulation? That will determine the current carrying capacity of the cable and therefore the size. The length of the run will also determine the cable size. The type of cable will determine the cable size also.

Are you actually going to connect this yourself?


Hi the cable will be clipped to wall, I guess uncovered but it needs to be armoured as it's in warehouse environment. Not buried in the ground. Will be passed by edged of the wall around 3 metres from the ground.
 
All them materials are easily available off the shelf at several places in london, there's 1 day maximum work there so you should easily get an electrician to do that by thursday, leaving a whole day for it to get down to temperature.
You need to locate an mcb for that board, providing there is 3 spare ways. that will be your major problem, though there are ways an electrician can get round that problem
 
Thank you for the help.

I will go with 40m 2.5mm 4 core SWA cable and cleats. I will not touch the box or do the insulator. I will have the electrician do that. I just route the cable across the wall.
 
As Bas said above this is not really a DIY job but most commercial coldrooms ask for a 32amp supply, rather than waste your money. for the extra cost it may be prudent to get 4mm
 
Read your PDF it really tells me nothing. There are two ways of starting and running a three phase motor, with contactors, and with an inverter, with the contactors there is a start load, and with refrigeration the speed of starting is very important, and also the volt drop. The compressor must get up to speed before the gas gets up to pressure or it can overload.

So although the run amps are under 5 amps, it is the start amps which is important. Most units will ask for either a 16A or 32A supply when using a contactor, it could be star/delta start or direct on line there is a huge difference in start amps. The more modern inverter is a completely different system, the motor does not stop/start but adjusts speed, these use far less to start.

Your 2.5 mm² will just about power a 16A socket keeping within volt drop. But there will be a volt drop to the board, we don't have test figures so can't say if it will be OK. It is not a DIY job, as said getting a MCB for that board could be hard, and if it needs a type C or D rather than normal type B then more of a problem. If not inverter drive then also phase direction.
 
I found an electirican who is coming tomorrow.

He is suggesting 5 core 2.5mm will be fine

As there are only 4 bends and 40m routing.

While here it's been suggested a 4mm cable

Power consumption 2566 W each phase.
Current consumption 4,3 A each phase.
The refrigeration spec is attached for your review.

All I have is the unit spec sheet which I attached earlier


Obviously I prefer to buy 2.5mm as it's cheaper so my questions is would it be satisfactory ?

The cable will be used only for the unit.
 
Using 2.5, he will have to fit a lower rated MCB in the board, if you want to increase the chance of the unit tripping one day and losing 5 grand of stock to save 40 guid thats fine.

If he is an Electrician and knows his stuff then go with it, strange choice of 5 core, as if swa there's no need for the extra expense over 4 core.
I would guess hes cutting corners by using Sy flex.

Ask him what size Mcb hes fitting and has he sourced one yet.

Inside the coldroom box there will likely be internal fusing to protect the unit, so an overrated supply is preferable, its likely with 2.5mm them internal fuses will be rated higher than the supply he installs
 
SW 2.5/2
2.5mm² 6942X 2 core SWA Steel Armoured Cable
per Metre £1.00
per 50 Metre £46.50


SW 4/2
4.0mm² 6942X 2 core SWA Steel Armoured Cable
per Metre £1.32

per 50 Metre £61.00

Extra cost to use 4 mm is £ 14.50
buy 50 metres to allow a cpuple of metres at each end so that the electrician can dress ( bend as necessary ) the cable to get it to enter the fuse board and freezer unit in the correct direction.

But as has been said there is a lot more to this than just an electrician connecting the ends of the cables. Full compliance with Health and Safety regulations for one thing, an electrician who has not worked on conmmercial / industrial installation may not have the knowledge, experience and qualifications to design and install with full compliance.

Is the Landlord aware of this new electrical load and has the DNO ( the people who maintain the cables supplying power to premises ) confirmed this extra 2.5 kW of motor load is acceptable to them.
 
With a non inverter refrigeration unit it has an overload to switch off the motor should it try to start when the pressure is already high, if the volt drop is too much this over load will activate often, however it is not designed to do that, so it will fail. When working in Algeria that was the most common reason for unit failure, they can be changed without dropping gas, however that is after it has failed so you have lost the stuff in the unit.

Is it really worth taking the chance? The problem is it does take some time before they fail, so one is not always aware of what the problem is.
 

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