outside metal halide yard lamp installation help please

[claptonfc]

Hi bit of a thicko with electrics so help is welcome.
I want to run three 400w metal halide lights in my yard 100meters away from nearest socket.
each lamp i have wired with a metre of cable and i think its rite in joining these in a ip66 junction box.
When wiring together what joining connection should i use.
Is it a case of 1 cable in to the joining block and then join the 3 cables from the lamps out the other side.
Your help is much appreciated. Please can you keep the info as simple as possible cheers.

chris

 

[Lectrician]

Well, yea.

But what type cable and installation method are using?

What size is the cable? 3 x 400watt metal halide, plus control gear PF losses is going to be a fair current, which is likely to require a larger CSA cable than you may believe. The cable CSA may also be affected by the type C breaker you are going to need for startup currents. You need to determine the max Zs at the end of the circuit, and ensure the cables R1 + R2 is suitable.

Cant say more until we know the exact lengths of cable, from socket to first lights, first light to second etc. Also need to know the distance and cable size to the socket.

Plugging these lights into a socket is also a sh1te idea by the way
A correctly installed and switched circuit would be far more suitable.

 

[resq]

Get a qualified sparks in mate its a long run of 100m

I think it's part P notifiable, but not sure

lectrician you beat me

 

[claptonfc]

so errr im going back to a plug in the portakabin and the 3 lights will be running off the same pylon does this help anymore.
I did want a basic answer lol
cheers tho lads.

 

[Lectrician]

the basic answer (then) is to get a spark in to calc it for you.

If you do not, you may use a cable which does not have adequate mechanical protection. You may install it in a manor that is in appropriate and cause temporary fencing to become live and leathal.

You may use a cable which is too small, causing a volt drop at the lights that reduce lamp life, and cause problems with firing and flickering.

The cable may also be too small, causing a high earth impedance, which would result in a high Zs, meaning that during a fault your fuse or MCB would never blow. This would mean your temporary fence remained live at upto 230 volt (or more), and ready to electrocute any passer by or intruder.

 

[Spark123]

Do not plug them in, not only is it a rubbish idea as lec says, it is also dangerous. They need to be installed correctly on their own circuit. As for part p (England+Wales), if they share there supply with a domestic dwelling they will be notifiable.

 

[Lectrician]

Unplug some inductive MH fittings with their great PF correction caps, make sure you do not touch the plug pins. Youch.

That is one reason it is not adviseable to plug them in.

 

[Spark123]

^^Yep, been there, done that too

 

[ricicle]

My other half's hairdryer is a bit lethal too if you touch the plugtop pins after unplugging.

 

[Chri5]

Outside wiring isn't really the thing for a total numpty (well your words...).

Insurance, safety, health and regulation issues.

But if you want it simple ->

1200w of lamp load = 5 amps.

Cable should be 2.5mm armour, hi tuf, or you could get away with artic flex.

I need to know how you intend to support the cable and the routing of the cable between lamps and back to the switch / main power feed to recommend which.

Will you be clipping to wall or eve's, all will it be catenary (aerial) runs?

These boxes will do

Run a cable from the furthest lamp to the middle lamp, then a cable from the middle lamp to the 1st, then from the 1st to the internal switch or junction box location.

At this point you need to pick up a live either via the existing lights (having confirmed that the circuit design won't fail due to the extra 1200w load), or via a socket circuit.

At each of the junction boxes you will need to join all the cores of each cable together, colour for colour. Make sure the cable enter from UNDER the junction boxes and leave enough slack on each (6-9") to form a drip loop and future remake off spare cable.

If you use the socket circuit 1200w will not cause any circuit design issues. but you will need a fused spur with a 6 amp fuse.

Some use the switch spur as the light switch which is ok- although I'd tend to have a switch near a door.

Hope that's clear enough, be safe and if in doubt get a sparks in and offer to run the cable .

 

[bernardgreen]

Unplug some inductive MH fittings with their great PF correction caps, make sure you do not touch the plug pins. Youch.

That is one reason it is not adviseable to plug them in.

Which is why an old hand used to fit a small incandescent lamp on the feed to bleed that charge away when he made a batch of lighting units.

 

[ricicle]

1200w of lamp load = 5 amps.

You are forgetting the efficiency and power factor (if no correction fitted) of these fittings.You could possibly be looking at double that ie 10amps

 

[Spark123]

Don't forget to multiply by 1.8 for discharge lighting

Bah, beaten by Ricicle!!

 

[Chri5]

b0110cks

So there all via one post and 'float' from the post to 3 destinations?

100m total run length is just on the edge of limit for 2.5mm cable.

I'd suggest 4mm between building and post, then 2.5mm from post to each light.

Personally I'd suggest seeking a pro's advice and services.

Are the lights for security or to use for work activities such as loading etc.
If they are, get the job done by someone who will make sure it's done properly.

There were 6 answers between me seeing the post and penning my last post, I'm off for a beer

 

[claptonfc]

Thanks for all the advice i will look into the cost of getting electrician to do it.

Or ill use cris5 help and maybe use artic cable.


Thanks again