Dos this sound correct? New plug installation.

[Ian293647]

Hi Everyone,

I'm installing some extra power sockets in my garage so that I can run a number of high performance computer servers in there. The computers run http://folding.stanford.edu/ Folding@home so are on 24/7. They help crunch mathematical data for medical researchers around the world with the hope that distributed computing power will help fight things like cancer etc. My electric is going to be mental but it's my hobby and it's a good cause. :/

The computers have two 1000W power supplies each and will draw close to that meaning that I can't use the plugs on the wall as there would be too much draw.

I am planning to install a 63A MCB in the unit (this one http://www.ebay.co.uk/itm/Eaton-63-...K_BOI_CircuitBreakers_RL&hash=item27dd03a9ad) and use 10mm cable to four dual sockets. There are four computers, each with dual power suppies.

I'm just getting ready to order my stuff online but was hoping someone here could confirm that sounds okay.

I know what I'm doing with computers but I don't have much experience with electrics. If I'm wrong here please feel free to ridicule, point and laugh or generally abuse me - just help please

Thanks!

Ian

 

[westie101]

Are you sure that you have got the load of the servers correct? 1000W is about 4.5A at 230V
If you mean 10000W you will be getting close to the maximum capacity of a single phase service so will need to increase your supply capacity!

 

[Aragorn84]

2000w is a perfectly safe draw for a normal plug/socket arrangement, especially as given there are two PSU's, each plug is only dealing with 1000w. A standard plug can flow just over 3000w, though they can get a bit hot if used continuously near their limit.

You'll find it fairly difficult to connect multiple sockets together with 10mm cable you propose for your 63A circuit.

I'd probably consider running a pair of 20A radials, using nice cheap 2.5mm cable with a pair of double sockets on each. Ofcourse you will need to ensure the suitability of the cable depending on how the cable is run.

Depending where you live, then to keep things legal you may really need to have a spark install the new circuits.

The other issue, is that with a continuous draw of 8000w, you may find that other loads in the house, such as your cooker or electric shower could result in you exceeding the maximum supply current of either your consumer unit, or service fuse etc. These things will need confirmed by an electrician.


With that much computing power, i'm surprised your folding with it, and not mining cryptocurrency...

 

[Ian293647]

Wow, thanks for the quick responses!

Yeah, they are definitely 1000W PSU's, two of them per machine.

Why would it be difficult to connect multiple sockets together? Just because of the thickness of the wire?

Aragorn, these are my old bitcoin mining rigs actually. I had them in work in the server room but replaced them recently with KnCMiner ASIC rigs. I was going to use these for alternative cryptocurrency but a friend put me onto the folding@home thing and I've been using these for that since.

Sorry, I don't know what a 20A radials is I'm open to different ways of doing it as I haven't bought anything yet. My friend is an engineer and said he'd help with the MCB installation as he has a fluke and a little bit more knowledge than me. Would I still need a spark? How much would a spark cost if I was to run the wires to and install the four double sockets?

Thanks!!

Ian

 

[Aragorn84]

20A radial is just a description for a 20A circuit that looks something like this:

http://www.ultimatehandyman.co.uk/radial.jpg

Protected by a 20A MCB (or other relevant device).

And yes, the 10mm cable simply wont fit into the terminals on the socket. You might manage one socket on the end of a piece, but not multiple sockets, because you wont be able to squeeze two wires into one terminal.

If your electrical engineering friend has the correct competency to complete the work, then i'm sure he'd do just fine, but really he needs to be the one designing the installation.

Similarly helping a spark out running the wires and fitting the socket is fine, but really you need to have discussed it with him first because its his name that goes on the paperwork to say he designed it etc.

 

[Ian293647]

Yeah, I didn't think of that (speaking to the sparky first about running wires etc). My brother in law says he knows a sparky but I'm quite interested in trying it myself first, safely of course.

A 20A would be easy enough I guess as there is plenty room in the unit for more breakers.

What is the limit you can draw to a house anyway? It's a detached house. I assume there is a max?

Thanks for your help btw. Much appreciated.

Ian

 

[RF Lighting]

It all depends on the size of the service from the supplier to your house. Some of the older supplies round here are still only 30A, but generally they'll be between 60A - 100A, but the supplier will not be too pleased about you drawing full load capacity or near to it for long durations, as it limits the amount of power available to the rest of the consumers on the same distribution circuit!

 

[Ian293647]

It's a new build that I live in so hopefully it won't be an issue then. I doubt I'll be drawing full load as my electric bill would be horrendous and this is only a charity type thing for me.

Ian

 

[SimonH2]

Yeah, they are definitely 1000W PSU's, two of them per machine.

Have you actually measured the power drawn vs quoting the rating off the rating plate ? There is usually (especially in IT) a big difference between what's on the rating plate and what is actually drawn. And there tends to be one power supply size for all configs - so in a less than fully loaded box there can be considerable spare capacity.

 

[mfarrow]

Yeah, they are definitely 1000W PSU's, two of them per machine.

We have a server at work that is plugged into only one. The power supplies are hot swap-able and are meant for redundancy, not necessarily running both together to keep the machine going. We get a blinking light telling us of a 'failed' supply but that's all.

Even adding up the rated power of the components inside won't get you anywhere near 1000W unless you add loads of hard drives, a big graphics card, and start playing games on it all day.

 

[Ian293647]

It's not like a normal server, I custom built it and although it has 2 PSU's they are powering different parts of the computer at the same time, it's not a redundant power supply.

It has five high end graphics cards which perform cryptographic functions at full load 24/7. The PSU's were selected specifically to provide just over what the system needs on full load, I think I calculated full draw is just over 1850W when I built them but I work on 2000W to have some freeplay.

Is there any way of finding out what the supply to your house is without calling up the provider?

Thanks!

Ian

 

[Taylortwocities]

It's a new build that I live in

OK, new build. Good. With your house documents you will have been given the Installation Certificate for the electrics in the house.

The first page of this will detail the supply including the type and the size of the supply fuse. What does it say?

 

[SimonH2]

...I think I calculated full draw is just over 1850W when I built them but I work on 2000W to have some freeplay.

Have you considered water cooling, then you'd have constant hot water in the tank While it's made in jest, it's not that daft a suggestion - why waste all that heat if you can put it to good use ?

 

[electronicsuk]

It's not like a normal server, I custom built it and although it has 2 PSU's they are powering different parts of the computer at the same time, it's not a redundant power supply.

It has five high end graphics cards which perform cryptographic functions at full load 24/7. The PSU's were selected specifically to provide just over what the system needs on full load, I think I calculated full draw is just over 1850W when I built them but I work on 2000W to have some freeplay.

Buy yourself one of there. I bet the system won't be drawing anywhere near as much power as you think, even with five high end graphics cards.

 

[Aragorn84]

I've a similar rig with two high end cards, its pulling 680w at the plug continuously while mining.

I think my cards are rated at 250w, plus the mobo/CPU itself, plus inefficiencys in the AC/DC PSU, gives you the 680w end figure

5 card rig would probably be in the 1700-1800w range like he says.

Mines in my study, and the "waste" heat means i dont need to run the heating during the day while i work. If it was quieter i guess it could go in the lounge and heat the sitting room, but its really quite noisey.