LED Tube Lighting circuit

[Ziggy1979]

Hi Everyone

new member and visitor to your forum so please be gentle! To ops, please excuse if I have posted in the wrong forum.

i am not an electrician nor do I intend to install the circuit I am asking about. I just need to understand what's going on to ensure I know what and why I'm getting it and the pros and cons.

we are opening a gym and having about 100 LED tubes (replacing fluorescents) installed mainly on the gym floor with some IP65 rated for the changing rooms. The electrician said it would be installed as a radial circuit (ie a few difference ones) but I asked the LED supplier and he said it should be installed as various ring circuits. My limited understanding of lighting circuits is that they are done in radial circuits.

ive read of high integrity earthing but I'm not sure that applies to LED tube lights so, other than cost more in wiring and possibly labour, what is the norm and what should I be getting and why? Electrician simply says supplier doesn't know what he's talking about but isn't really explaining much. All I want to do is understand the pros and cons and to know what I need and why.

thanks for your help!

Zigs

ps - there is 3 phase power

 

[Richard Burns]

Welcome to the forum, hope it is useful for you.

For your LED tubes I can see no reason for installing the circuit as a ring; multiple radials would be my expected arrangement.
LED tubes can generate some leakage current but you would need to check the manufacturers data for the actual likely level.
If it is high then the circuit needs splitting down not forming as a ring.
The fittings should also have the details of the number of fitting permitted per MCB.
With the low running current demand more fittings may be expected on one MCB but the inrush current may limit this.
High integrity earthing is usually only relevant to socket outlets and the resolution would be using fixed wiring (which you would already have).
If high integrity earthing were required then only the earth would be a ring.

 

[Knobhead]

You’re electrician has it right for a multiple point lighting circuit a ring is best. Multiple radials for the same circuit are a mess. OK a ring isn’t as easy to run and test, a good electrician will have no trouble with it.

Regarding high integrity earthing, are you planning on plugging you’re computer in to the lights? A suitably sized cable for the lighting circuit rings will provide the earth path required.

There is the problem of the maximum fitting on a MCB, but with suitable switching (contactors) and the correct cable? A good electrician will sort that for you.

Regarding lighting on a ring circuit, the last place I worked before I retired had four 32A 3Ph lighting ring mains on contactors in one workshop alone. Each fitting fused down as required.

 

[Richard Burns]

Tony is much more likely to provide accurate information than I am, so be aware.
The design of ring circuits for non BS1363 (sockets) accessories is not covered in the wiring regulations so needs careful design to ensure safety, though the consistent nature of the load makes this more straightforward.

 

[Ziggy1979]

Richard/Tony


thank you both very much for your help/advice - you do extend a warm welcome to newbs!


i have asked that lights be run on their own lighting circuits eg a few on the gym floor, one for entrance, one for IP65 rated bathroom lighting (men's, ladies, disabled). We also need other circuits:
1. 3-4 rings for treadmills (3-4 treads per ring). We've been told that we need Type D breakers to allow for the high current drawn when starting the (induction) motors on the treads.
2. 1xring in the office to allow for 2PCs, hifi/amp, printer, CCTV, phones, etc.
3. 1-2x rings for Hoover (ie sockets around the gym floor and in the treatment rooms and bathrooms.
4. We also need additional supplies eg for access control at turnstiles, 2x3A supplies to gas water heaters, 2 low energy AC coolers, etc.


im wondering if it might be better to have an electrical design done and then get someone in to do the actual work. Is there any value in doing this for this type of project? If so, are there any ball parks (ie at what point are they asking too much) for such a design?


thanks again for all your help!


Zigs

 

[Richard Burns]

Depends on the design you want and the budget you have. If you are looking for specific lighting effects or need certain limitations on what you want installed then it might be worth running a project.
If the issues are all straightforward then so long as the electrician knows in advance what you need now and what you may be planning for, the size of supply you have and any special conditions e.g. like identifying hoover circuits from tread mill circuits, then he should be OK.
However not wishing to make assumptions but if you are asking here and are not sure of your electrician, maybe it would be a good idea to get a second opinion locally from someone who can see the site and plan accordingly.

 

[Ziggy1979]

Thanks again for your help!

i am thinking of getting a few different Guys in to quote and advise. Problem I have at the moment is that the supplier said one thing and the fitter another. In my very limited knowledge I am inclined to side with the electrician (ie multiple radial circuits eg each with 10-20 LED tubes (5ft @ 22-25W/tube). That said I agree with Richard and will get a couple of other guys in to quote and see what they advise. Price and a feeling of comfort should then help me decide who to go with.

what I don't want is overkill - in both design and install costs for what is a smallish gym with less rings, etc than our house (albeit that its a larger area).

thanks again for everything...I'm sure I'll be back with more questions soon!

 

[telectrix]

with the amount of LED tubes you will be buying, i'm sure that the manufacturer will be happy to design it for you.

 

[Ziggy1979]

Hi Telectrix

thats a great idea! Will definitely check with the manufacturer/supplier!

btw I'd thought of having PIRs to detect motion. The supplier mentioned getting sensors that also turned lights on or off depending on the flux level in the room. Other than the additional profit he will make, would you guys advise for or against lux sensors (eg are they accurate enough, etc. especially as there are some relatively cheap ones and others that are really pricey).

thanks again!