Need some advice on new server room

[binky]

if it's on a 50A MCB the cable is more likley to be 10mm, but given the nature of your business and constant running loads I think I would be inclined to go bigger, unless you have a 3 phase set-up?

30mA protection on that lot is not a good idea, a set-up with multiple circuits (ideally 1 per server) to spread the loading would be far better given the fact you need a very reliable system. Better off without RCDs if that is possible?

post as many pics as you can, it's hard to give advice with half a story.

 

[Lurch]

Can I just ask, are you definitely in the UK? You keep using American terms so I'm just wanting to make 100% sure we're all on the same page here.

 

[James2324]

Im definitely in UK what American terms have I used? Didn't even realise 

 

[James2324]

As it stands at the moment sorry I can't get pics. Other than of the consumer Unit and the sub panel although don't know what else I could take a pic of?

i have a consumer unit in my house with 200a coming in.

80a RCD. 30ma

sub panel cable is total length 13.5mm x 7mm which could be t/e cable would that make a difference?

the subpanel has only two circuits to split up the 50a which I'm not happy with either. I think I should of not bothered getting a local. Just like helping local businesses since I am a local business too.

the 13.5mm is in a trunk however I can remove the trunk if that helps the cable cool more?

other than me measuring the actual cable I can't really tell what kind of cable it is. 

its only around 2M long.

On my electrical cert it says 1 phase 2 wire with a tick and 3 phase is n/a so I assume maybe it's not 3 phase 

 

[Murdoch]

Why don't you tell us the full story.... I simply don't believe you commissioned a spark to install a submain and CU for IT servers and they've come up with the solution you have outlined....

 

[James2324]

the full story? I've given everything what have i missed?

the local electrician was recommended to me by the local builder who built the warehouse on my land

Maybe I didn't give him enough information in regards to the servers? I told him the number of servers and the total wattage draw that I will be pulling and asked him what would be best and he said this will definitely run he required wattage no problem 

 

[James2324]

However I am nown to be paranoid when it comes to safety so wanted to get second opinions 

 

[Murdoch]

the full story? I've given everything what have i missed?

the local electrician was recommended to me by the local builder who built the warehouse on my land

Maybe I didn't give him enough information in regards to the servers? I told him the number of servers and the total wattage draw that I will be pulling and asked him what would be best and he said this will definitely run he required wattage no problem 

I simply don't believe that anyone would have designed the solution you outlined with the knowledge you were going to install a lot of IT equipment........

 

[steptoe]

The set-up as you describe it, is, IMHO, simply, not fit for purpose , as you intend to use it.

 

[James2324]

How is IT equipment any different to a TV or a fridge freezer? 

Im no expert but I don't see the difference. 

This is what he did. And I told him exactly the same is im telling you. I've got a bigger company coming out on sat.

ill see what he says then. 

Like I say I'm no expert I wish I could understand this stuff. Any area of computing or many other areas I can get my head around but all this to do with electrical circuits hurts my head 

as far as I understand it so far is I thought if you need 50a worth of electricity you get a cable which can withstand 50a without overheating and then a 50a breaker and your good to go...

guess i I have absolutely no clue!

 

[Murdoch]

Your immediate problem will be nuisance tripping of the RCD due to the accumulated earth leakage...... which IT kit is re-known for!

 

[James2324]

Is it standard practice for someone to check an RCD without me asking him? I don't think he even looked at my RCD 

My RCD has been in my home CU since I had an extension done and rewiring around 4 years Ago

 

[Andy™]

sounds like you have got a domestic installer who only knows how to lash in a few basics circuits and cant think for themselves, and has no knowledge of more commercial stuff or IT systems

 

[James2324]

Your immediate problem will be nuisance tripping of the RCD due to the accumulated earth leakage...... which IT kit is re-known for!

Murdoch if you don't mind helping out a complete novice in regards to this...

how is earth leakage calculated then?

for all of these servers how would you calc the tolerance the RCD Should allow for each server?

im really interested in understanding all this stuff

 

[Andy™]

How is IT equipment any different to a TV or a fridge freezer? 

computers have earth leakage by design. this needs to be taken into account. as i said in an earlier post, i bet his hasnt allowed for high intergrity earthing with would usually be required in installs like yours. leakage is generally its 3.5mA per PC but can vary

 

[Murdoch]

Is it standard practice for someone to check an RCD without me asking him? I don't think he even looked at my RCD 

My RCD has been in my home CU since I had an extension done and rewiring around 4 years Ago

If a sub main has been installed from your CU, they are obliged to test said circuit from the origin and if RCD protected, test said RCD.......

Murdoch if you don't mind helping out a complete novice in regards to this...

how is earth leakage calculated then?

for all of these servers how would you calc the tolerance the RCD Should allow for each server?

im really interested in understanding all this stuff

You can't calculate earth leakage...... 

 

[James2324]

computers have earth leakage by design. this needs to be taken into account. as i said in an earlier post, i bet his hasnt allowed for high intergrity earthing with would usually be required in installs like yours. leakage is generally its 3.5mA per PC but can vary

Yeah I've checked the cert he gave me... it says he tested RCD but obviously he tested it when I didn't have any servers here 

 

[kerching]

I would be looking at....

bigger submain

spread loads over over a LOT more circuits

multiple UPSs....by largest client insists on n+3.  Sometimes n+5

stanby Genny ?

AMF panel?

it really depends on how much resilience you want and how much you want to spend

 

[Andy™]

Yeah I've checked the cert he gave me... it says he tested RCD but obviously he tested it when I didn't have any servers here 

cable size should be on there too. i note you also said its in trunking... if so and its 6mm then its rated at 32a.... on a 50a MCB is not exactly good planning or design...

 

[James2324]

cable size should be on there too. i note you also said its in trunking... if so and its 6mm then its rated at 32a.... on a 50a MCB is not exactly good planning or design...

Where abouts does it say cable siZe?

i only see cable size for sub circuits off the sub main. It looks like he didn't fill the bit in about the cable to the sub due to being directly connected to main unit?