New electrician needs help with recessed lighting please

[cr0ft]

Hi all,

I normally work in domestic properties and am very comfortable doing this. Last week I got a call which took me out of my comfort zone. The work is in a small modular lab at a hospital near me. Basically, there are 2 sets of 3 recessed 600x600 ceiling lights with flourescent bulbs. Each set is wired in series and each set is controlled by 2 switches - a 1 way on/off switch and a separate dimmer switch.

The problem is that 1 light has gone from each set. The remaining lights work fine and dim correctly, but the 2 lights in question just won't come on.

Each light has 4 bulbs so unless all 4 bulbs have failed from each light I'm convinced that isn't the cause.

Wiring all appears fine.

There are 2 electronic modules in each light, an emergency lighting module and a ballast module. The former is self-explanatory but I have no idea what a ballast module is and am keen to learn!

There is 230V coming into the ballast module but negligible voltage coming out so I am guessing the solution is to replace the ballast modules on both lights but I want to be sure before I purchase anything.

Thanks in advance for any comments. A photo showing the light fitting is attached.

 

[Steve3948]

Maybe series wired lamps, need to change all failed lamps in unit, best to change all 4 anyway, but even a new lamp can be duff so don't get caught out. Use 4 known working lamps to start with.

Does it work on emergency ?

 

[cr0ft]

Thanks. Could you possibly give me a thicko explanation of what the ballast module is supposed to do please?

 

[Steve3948]

You should already know this, but if not do a google for Lighting Ballast

 

[husky2013]

A ballast in a fluorescent fitting does 2 things :

1) it steps up the voltage to drive the lamp

2) it provides a 'Load' or operating resistance whilst the lamp strikes!

without sounding rude, but properties of ballasts are pretty simple, im only on my 1st year and we have covered this!

P.S Bulbs are something that you plant in your garden! its a Lamp

 

[Steve3948]

P.S Bulbs are something that you plant in your garden! its a Lamp

Haha that's something I always tell customers, and they look at you all weird.

 

[husky2013]

lol steve, i used to call them bulbs then i met my beloved, whom corrected me and iv called them lamps ever since, its bugs me now when people call them bulbs, i tell them off!

 

[donnie1986]

This sounds fairly familiar. Do your other 4 fittings have emergency packs in them? If not I would hazard a guess that your emergency packs are playing up. I know from previous fittings that only one lamp would he wired through the pack. If this is the case and all the lamps are out then, I would have thought you have a problem with your ballast.

Also I very much doubt the circuit would be wired in series. It would be wired in parallel, and looped on.

You may also have a conflict between the dimmer and the flourescent fitting with the emergency. This is the problem with flourescent lights. Pin pointing a fault can be extremely difficult.

Good luck

Donnie

 

[kerching]

This sounds fairly familiar. Do your other 4 fittings have emergency packs in them? If not I would hazard a guess that your emergency packs are playing up. I know from previous fittings that only one lamp would he wired through the pack. If this is the case and all the lamps are out then, I would have thought you have a problem with your ballast.Also I very much doubt the circuit would be wired in series. It would be wired in parallel, and looped on.

You may also have a conflict between the dimmer and the flourescent fitting with the emergency. This is the problem with flourescent lights. Pin pointing a fault can be extremely difficult.

Good luck

Donnie

+1 ^ I agree with what the new boy above says [ He who shall now, probably, be known as Osmond ]........... :coat

 

[Rossmc]

P.S Bulbs are something that you plant in your garden! its a Lamp

I remember my college lecturer telling us that daily, now I correct random people nearly daily lol

 

[SLIPSHOD & SLAPDASH]

I planted some lamps today (really !!), waiting for my neighbours to ask . Will have to take a pic

 

[kerching]

http://www.siastraining.co.uk/Product%20Scans/Budget%20Bulb%20300dpi.jpg

.............................................................. :run

 

[batty]

It had to be a Tridonic ballast that failed.

:slap

 

[sellers]

When you say series you may have been confused with the dimmer cables. Some HF fluorescents have terminals 0-10v for dimming, so you have a normal 240v supply switched to each fitting and then a 0-10v supply from the dimmer to each fitting.

 

[sparkyjoe]

A ballast in a fluorescent fitting does 2 things :1) it steps up the voltage to drive the lamp

2) it provides a 'Load' or operating resistance whilst the lamp strikes!

without sounding rude, but properties of ballasts are pretty simple, im only on my 1st year and we have covered this!

P.S Bulbs are something that you plant in your garden! its a Lamp

he probably only did a 5 week course.

 

[Manator]

he probably only did a 5 week course.

Perhaps with this forums help he can become a very valued member of the trade,I passed my 2391 in 27 minutes due to the fact that my wife was giving labour at the time and I did not want to be late. I never had the help of forums like this one, and now whilst I think that I know it all I am constantly reminded of how little I actually know.

 

[sparkyjoe]

Perhaps with this forums help he can become a very valued member of the trade,I passed my 2391 in 27 minutes due to the fact that my wife was giving labour at the time and I did not want to be late. I never had the help of forums like this one, and now whilst I think that I know it all I am constantly reminded of how little I actually know.

i agree with you to a point, and as they say, every days a school day but at the end of the day practical experience with a good electrician can never be replicated with a 5week course and a internet forum.

 

[Manator]

I actually thought the same, until I got to know the exploits of some of our members, I even had a PM from a well respected member who had the pleasure of working with one of our 5 week wonders, his message to me was along the lines of how surprised he was at the extent of knowledge that he had, and if I ever needed a recommended electrician, he would suggest him above others.

I will point out at this stage that the member mentioned can smell and eat a fool for dinner, so if he says he is OK he really is.