Author Topic: Electrician needed (Read 1807 times)

Big Mouse · « **on:** February 04, 2007, 07:08:51 pm »

Any sparkys on here? I need some advice about wiring up the support lorry - not vehicle electrics but wiring from the generator into the truck to run things like the shower, kettle, lights etc.

Titsy · « **Reply #1 on:** February 04, 2007, 07:18:44 pm »

Shoot... Anything I can't answer I will check with my old man, who works as an electrician....

Big Mouse · « **Reply #2 on:** February 04, 2007, 07:51:56 pm »

Thanks Titsy

I've got a 7.5 KVA genny to run all the crap I need for race weekends. What I want to do is wire up the lorry as I would a house and just be able plug the genny in when I'm set up. Do I need to have some sort of 'consumer unit' as I would for a house to distribute the power and then just put in a ring main type of scheme or can I just run one cable linking all the outlets that just plugs straight in to the genny. I don't want to run a load of extention cables if I can help it

I'll need to power a kettle; a small fridge, a small flourescent tube in the lorry, a small heater (low heat back ground type of thing) a shower (basic model), a small lcd tv and a dvd player, I;ll need to charge the lappy too but not run it off the genny as it isn't an AVR model.

I also need to power the two flourescent tubes in the marquee and the nitrous heater which is basically an immersion element in an ally tank plus the battery charger. I'll probably weld an air take off into the lorry as I only need air to inflate tyres.

Total power if everything was on at the same time (never) would not exceed 6000 watts even with surge.

Condensation might be an issue as it builds up a bit when the lorry is left outside (as it will be) so any advise on that would be good

55starchief · « **Reply #3 on:** February 04, 2007, 08:00:20 pm »

As a qualified sparky i would run a small consumer unit mate, do any of the places you go to have a mains hook-up? if so i would go with a changeover switch.

For any external stuff i would add a couple of BS4343 sockets to the outside of the truck and protect them with an rcd

55starchief · « **Reply #4 on:** February 04, 2007, 08:06:01 pm »

Would also probably wire it in plastic conduit, makes for easy modification if you need to add something else in and also offers some mechanical protection

Big Mouse · « **Reply #5 on:** February 04, 2007, 08:07:30 pm »

Quoting: 55starchief

As a qualified sparky i would run a small consumer unit mate, do any of the places you go to have a mains hook-up? if so i would go with a changeover switch.

For any external stuff i would add a couple of BS4343 sockets to the outside of the truck and protect them with an rcd

Santa Pod offers a hook up but its pricey, about £55 for a 2-3 day weekend last year and probaly more this year but having a changeover switch would be useful. They've got the upper hand as all petrol gennys are banned from this year (mines lpg)

So can I use a normal household consumer unit? or do I need a special type for gennys?

Big Mouse · « **Reply #6 on:** February 04, 2007, 08:09:08 pm »

Quoting: 55starchief

offers some mechanical protection

from? do you mean against condensation? I've got a load of plastic conduit left over from the office refit that I was going to use

55starchief · « **Reply #7 on:** February 04, 2007, 08:15:08 pm »

Quoting: Big Mouse

So can I use a normal household consumer unit? or do I need a special type for gennys?

You can use a normal consumer unit, where are you thinking of putting it? if its in the living section i would go with a plastic case if its going in the workshop side metal clad. Also any sockets in the workshop section would be better metal clad

Quoting: Big Mouse

Quoting: 55starchief
offers some mechanical protection

from? do you mean against condensation? I've got a load of plastic conduit left over from the office refit that I was going to use

Mainly protection from things hitting it, if you wire it in twin and earth the cable wont have any mechanical protection

Condensation shouldnt be too much of a problem aslong as its not like a rain storm

Titsy · « **Reply #8 on:** February 04, 2007, 08:19:27 pm »

I would suggest that all the wiring is run in conduit to help protect against the moisture, and getting a good earth on the chassis and back to the genny is a must... For convenience i'd stick a BS4343 plug on the outside of the truck and use a link cable to the genny.

You definatly need an RCD for the outside stuff, and for the sockets and shower. You could do without one for the lights, but if there is a chance of damp it is better to be safe than sorry...

I'm assuming the shower would be electricly heated, which will pull a fair wack of juice. You'll need to check the current consumption and sellect cable that is rated well, and a closely matched RCD.

What power rating would the heater be? If it is a permanent feature you may wish to run it off a fused sper...

I'd suggest industrial fittings all round.

55starchief · « **Reply #9 on:** February 04, 2007, 08:24:52 pm »

Quoting: Titsy

For convenience i'd stick a BS4343 plug on the outside of the truck and use a link cable to the genny.

Yeah not a bad idea, unless the genny is fitted to the truck

55starchief · « **Reply #10 on:** February 04, 2007, 08:33:57 pm »

I would also make any extension leads with armaflex and the hookup to the geny if external

55starchief · « **Reply #11 on:** February 04, 2007, 08:52:14 pm »

Here is a changeover unit

http://www.lawson-his.co.uk/scripts/products.php?cat=Power%20Generators

We have a generac installed at my folks place but its much the same thing

You could do with out it and as titsy says add a BS4343 Plug to the outside of the vehicle. For a hookup lead from the genny to the truck i would go with a minimum of 4mm.

What size outlet is on the genny? 16A or 32A am guessing a 32A

Titsy · « **Reply #12 on:** February 04, 2007, 09:00:05 pm »

Quoting: 55starchief

What size outlet is on the genny? 16A or 32A am guessing a 32A

would have to be for 7.5kVA

55starchief · « **Reply #13 on:** February 04, 2007, 09:03:07 pm »

Quoting: Titsy

would have to be for 7.5kVA

not always, might be a pair of 16A's

Actually i would go with the changeover as the outlets on most hookups are 16A so you could change between the 32A inlet from the geny to the 16A of a hookup. Remember if you wire the 16A socket and 32A socket in paralell when one is in use the other will also be live hence the changeover switch

Big Mouse · « **Reply #14 on:** February 04, 2007, 10:05:54 pm »

OK, you've both lost me now

I'll need to work out what I want, where I want it and then I'll come back to you.

This is the genny http://www.worldofpower.co.uk/acatalog/SIP04478.html

The heater is a 450w, just a back ground heater really. I might get a gas one yet.

I haven't bought a shower unit yet but will take advice as to the best for the purpose

The genny is going to be mounted to the underneath of the lorry but removable for security so it will be well grounded

55starchief · « **Reply #15 on:** February 04, 2007, 10:10:39 pm »

Quoting: Big Mouse

I'll need to work out what I want, where I want it and then I'll come back to you.

No problem mate, i would definatly wire it in plastic conduit the 20mm round stuff not the square clip lid.

If you need prices let me know the number of sockets etc and i will see what deal my contact at the electrical wholesaler next door to work can do

Big Mouse · « **Reply #16 on:** February 05, 2007, 07:52:21 pm »

Quoting: 55starchief

No problem mate, i would definatly wire it in plastic conduit the 20mm round stuff not the square clip lid.

If you need prices let me know the number of sockets etc and i will see what deal my contact at the electrical wholesaler next door to work can do

Cheers

The stuff for the office was the square lid type, only because we need to get to it more often so I'll buy the round stuff. I can get it all through my account with the wholesaler here, it's just buying the right bits that I was concerned about and using the right type of wire etc

55starchief · « **Reply #17 on:** February 05, 2007, 07:56:10 pm »

Your going to need singles to wire it with,

2.5mm brown and blue
1.5mm brown and blue
1.5mm green and yellow

then how ever many sockets you want to put in etc

Big Mouse · « **Reply #18 on:** February 06, 2007, 06:06:29 pm »

Quoting: 55starchief

Your going to need singles to wire it with,

2.5mm brown and blue
1.5mm brown and blue
1.5mm green and yellow

then how ever many sockets you want to put in etc

Why singles instead of 'ready mixed'?

55starchief · « **Reply #19 on:** February 06, 2007, 06:08:43 pm »

Quoting: Big Mouse

Why singles instead of 'ready mixed'?

Its a lot easier to wire conduit with singles than T+E

Big Mouse · « **Reply #20 on:** February 06, 2007, 08:19:59 pm »

Quoting: 55starchief

Its a lot easier to wire conduit with singles than T+E

Ah, makes sense. I'll buy a coil of each

55starchief · « **Reply #21 on:** February 06, 2007, 08:22:37 pm »

you might want to get a draw wire aswell, helps to get the cables in especially if you add some after the initial wiring

Big Mouse · « **Reply #22 on:** February 06, 2007, 08:48:04 pm »

Just been measuring up, I need 3 doubles and 1 single inside plus the feed to the shower.

Would I need to run the sockets as a ring main or could I just wire them each seperately back to the consumer unit?

Titsy · « **Reply #23 on:** February 06, 2007, 08:51:09 pm »

It's always best to wire them as a ring.

***EDIT***

I'm sure it's what you meant to imply, but the shower feed should be wired to it's own dedicated RCD which is of a suitable rating.

55starchief · « **Reply #24 on:** February 06, 2007, 08:53:05 pm »

personaly i would run them as a ring just to be on the safe side. 2.5mm only has a current rating of 15A its not until you create a ring that it gets the 30A rating.

Although your genny cant supply 30A there is always the risk that on a big hookup you could see that.

You have to remember that you might know the loading of everything but not everyone thinks when the plug stuff in

Also running the wires in the conduit means you can simply add the return wires in as you go, you dont need to make a loop with the conduit