Generators

[fergiemac]

Hi, This might not be the right forum for this post but, here goes; We have been asked to supply power for campervans (20) at a small festival, We would have to run the power from Generators, our plan was to install 5 x 4 way 16amp outlets on posts, all properly protected. The problem will be cabling, What should we specify from, say, 2 x 10kva gennys, what outlets from the Gennys etc. Distro is no problem as it will be hired in, as will the cables.
Thanks in advance
p.s. All this work will be done by suitably qualified sparkys, just trying to prepare a bit for them

 

[Robin0577]

This is one of those where the person signing the certificate must also take responsibility for the design stage, will that be you? If not you need to get your sparkys on board right at the outset.

I would think this is a case for BS7909 (The snappily titled "Code of practice for temporary electrical systems for entertainment and related purposes") rather than the more usual BS7671 as used for permanent installations. You can get a copy here....

http://shop.bsigroup.com/ProductDetail/?pid=000000000030201299

 

[fergiemac]

Thanks Robin, I'll be involve with the sparkys all the way through, What I'm trying to do is Start to get some of the cable and such sorted out as I can't get hold of said sparkys for another month.

 

[westie101]

I would suggest you need to rethink your generator sizes, a modern caravan can easily reach it's 16A max load

 

[oldbutnotdead]

Make sure you whoever you hire the gennies from that you're running domestic type loads- in that power range you might end up with site generators which won't run microwaves, fridges, TVs etc. properly. You probably want to allow at least 10A for each vehicle (maybe more if your gig is in the winter/somewhere cold at night).

If you're hiring all the kit from one supplier, talk to them- they'll have Rubber Box or similar distribution boxes all IP rated and good to go.

 

[westie101]

Actually that is a point, most of the major generator hire companies (Aggreco, Energyst, Generator Power etc.)will be able to provide a "one stop shop" for this

 

[fergiemac]

Thanks guys, We hope to breaker the supply down to 10amps for each van, (they can like it or lump it) you usually only get around 5 - 6 amps abroad ! We'll be hiring from Aggreko so your suggestions make sense. I knew we could get the rubber box distro and cabling from them so will get on to them and seek their advice. The festival is in July on the West Coast of Scotland so (hopefully) it'll be warm enough and it's light 'til about 11pm at that time of year

Cheers again !

 

[westie101]

Aggreko will have done similar before so will be able to advise on generator size as well

 

[AdrianUK]

This is the business I was in until recently (spent 15 years on the road doing festivals & tours).

I think your genny size is way too small! I know from experience that in the chilly eve they will all produce their 2.4kw halogen heaters! (I do when we go camping Also bear in mind that a 10A MCB will allow 11, 12 may even 13A almost indefinitely before it trips ... and then its going to hold for several minutes. If you hire the distro from Aggreko it will have 16A MCBs on the 16A outlets - 10A doesn't make any sense for them. You'll also want RCBOs not MCBs.

For your 20 vans, allowing for a margin of comfort, I think you're gonna be looking at around a 100kVA set. It will almost certainly be a 3 phase unit and should be good for around 125A per phase. This may seen like over kill but other loads will appear ... site lighting? toilets? shower blocks? campsite catering? Will the 20 vans turn into 25 on the day?

Don't try to run the genny at 100% capacity - it wont work! If you try to exceed 70-80% capacity for several days you run a high risk it will fail on you. Better to come out of this having burnt a little more diesel & kept the power on than doing it on the cheap but having it keep tripping out. Don't forget fuel - as rough rule of thumb, 1 gallon of diesel gives you around 25 kwh of electric..... so the genny could be using upto 4 gals/hr. The gennys own belly tank should hold a days worth of fuel. Some of the bigger festivals I worked on would burn 6 - 8000 litres a day of diesel so it wont be quite the same problem ... but you still need to get your hands on it.

What about when somebody trips an RCBO? Will you allow them to reset it or will there be a duty sparks?

Adrian

 

[fergiemac]

Hi Adrian,
Cheers for this. I had thought we would need round about 100kva, but I want to split the power so maybe 2 x 50kva 3ph split dpwn to 32a outlets on distro. The reason for 2 gennys is to shorten the cable runs.

I want to run 32a into the hook up points (4 way units) with 10a RCBO's on the hook ups. As I said previously, abroad you sometimes only get 5-6amps so we wanted to give a bit more but still get them to watch what they're doing

All the other power requirements are taken care of by other gennys, sound, lighting etc so this is strictly for the vans

This is the 4th year we've done this festival but the 1st with this kind of set up.

Thanks again for your thoughts !

 

[bernardgreen]

Aggreko will have done similar before so will be able to advise on generator size as well

I have seen the service Aggreko provide and it is excellent.