Ireland Emergency lighting diagram?

[An Buachaillín Bán]

Hi all,

Just wondering if anyone would have a diagram, or know where I can find a link to a diagram, of how emergency lighting is wired, from fuseboard- ie mcb, control mcb ctu contactor and lights, please?


Thanks.

 

[MJPD29]

There multiple ways or doing it. Maintained or non maintained? And are they dedicated emergency fittings or combined? Is this a college question?

 

[timhoward]

Conceptually it's just like having two light switches for two groups of lights. A normal switch for the normal lights. And a key switch for the emergency lights that is usually 'on'.

The main thing wiring-wise is that maintained lights (which are on all the time) can be wired from any lighting circuit or their own circuit.
Non-Maintained lights are not on all the time, so the supply needs to be common to the normal lighting in the areas they are protecting. e.g. If lighting circuit 1 trips, then the emergency lights in the rooms that now have no lights need to come on.

 

[An Buachaillín Bán]

There multiple ways or doing it. Maintained or non maintained? And are they dedicated emergency fittings or combined? Is this a college question?

Thanks for the reply.
Predominantly non-maintained fittings. And most of the fittings are dedicated, for example EM bulkheads and spots in open plan areas, corridors etc. Not a college question, but I may have to install some soon.

 

[An Buachaillín Bán]

Conceptually it's just like having two light switches for two groups of lights. A normal switch for the normal lights. And a key switch for the emergency lights that is usually 'on'.

The main thing wiring-wise is that maintained lights (which are on all the time) can be wired from any lighting circuit or their own circuit.
Non-Maintained lights are not on all the time, so the supply needs to be common to the normal lighting in the areas they are protecting. e.g. If lighting circuit 1 trips, then the emergency lights in the rooms that now have no lights need to come on.

Thanks Tim. Much appreciated.

The buildings which I'll be looking after non- maintained for the most part. So take for example room 1 general lighting. I install NM em lights here and take feed from the same mcb feeding general lighting in room 1.

From Mcb to 6A control mcb- onto my CTU, which in turn, would feed the NC terminal of a contactor if there were a large number of lights on the circuit?

 

[MJPD29]

In that case probably a dedicated circuit(s) from board to contactor and then out to lights, switched by a key switch or timed switch for testing purposes. Or if no master switch then local switches in areas for testing.

 

[timhoward]

From Mcb to 6A control mcb- onto my CTU, which in turn, would feed the NC terminal of a contactor if there were a large number of lights on the circuit?

A typical LED non-maintained unit consumes about 3-4 watts. The older T5 bulb units are more like 20W. How many units are we talking about?

In that case probably a dedicated circuit(s) from board to contactor and then out to lights, switched by a key switch or timed switch for testing purposes. Or if no master switch then local switches in areas for testing.

To be clear, you are suggesting the contact0r coil is powered by the local lighting, right? As it's non-maintained fittings.

 

[buzzlightyear]

In that case probably a dedicated circuit(s) from board to contactor and then out to lights, switched by a key switch or timed switch for testing purposes. Or if no master switch then local switches in areas for testing.

no contactor ,separated circuit only and key switch for testing .

 

[An Buachaillín Bán]

A typical LED non-maintained unit consumes about 3-4 watts. The older T5 bulb units are more like 20W. How many units are we talking about?

To be clear, you are suggesting the contact0r coil is powered by the local lighting, right? As it's non-maintained fittings.

Any of the new installs will be NM LED fittings. It could be anything from 5-20 fittings.

 

[An Buachaillín Bán]

In that case probably a dedicated circuit(s) from board to contactor and then out to lights, switched by a key switch or timed switch for testing purposes. Or if no master switch then local switches in areas for testing.

It would be a master switch. So in terms of the wiring of it, supply from board ie for eg.10A mcb to the CTU or key switch, then onto contactor and from there out to circuit?

 

[timhoward]

I'm a little confused why you think you need a contactor to switch an 80W load (20 x 4 watts ) that draws 0.34 amps

 

[MJPD29]

@buzzlightyear in Ireland it's common to wire em lights through contactor(s) and panel mounted timer in commercial environments for ease of testing, depending on amount of them and load etc. Just an easy way of switching more than 1 circuit with 1 switch

 

[westward10]

There is a large retail chain in the UK doing this, one push button and a 3hr timer.

 

[Risteard]

As mentioned it's done through a CTU (central test unit) and contactors rather than key switches.

I.S. 3217 are the Emergency Lighting Rules which need to be complied with - it's not BS 5266. It's done a bit differently.

 

[jay sean]

There is a large retail chain in the UK doing this, one push button and a 3hr timer.

Is this boots? Ive been to some boots and they had panels with a few buttons for emergency lights

 

[westward10]

No not Boots.

 

[An Buachaillín Bán]

I'm a little confused why you think you need a contactor to switch an 80W load (20 x 4 watts ) that draws 0.34 amps

Forgive my ignorance Tim, but in what circumstance would you use a contactor for emergency lighting, as I've seen a few new installs recently where one is installed next to the control mcb and ctu for emergency lighting. I hadn't the opportunity to look behind the covers yet, but my understanding was it was switching the emergency lighting. One unit had only 4x NM em lights and when I tested through ctu the contactor pulled and em lights came "on."

I understand your point that having a 10 or 20 amp contactor switching a few 4w led fittings doesn't make sense. But just wondering what other scenarios would you use a contactor for emergency lights?

Thanks

 

[timhoward]

Forgive my ignorance Tim, but in what circumstance would you use a contactor for emergency lighting, as I've seen a few new installs recently where one is installed next to the control mcb and ctu for emergency lighting. I hadn't the opportunity to look behind the covers yet, but my understanding was it was switching the emergency lighting. One unit had only 4x NM em lights and when I tested through ctu the contactor pulled and em lights came "on."

My comments were based on installations I've seen in England and Wales and I've never encountered the system you describe which others have now explained is common in Ireland and sometimes in other places too. So best to disregard what I said!

If the system has non-maintained fittings, I'm imagining (with zero experience) that there's a contactor coil energised by each lighting circuit, and the supply runs through normally closed contacts in another contactor to all the others. And a button/timer closes the supply contactor for 3 hours cutting off the power to the others....
Maybe one of the Irish sparks could draw us a quick diagram!

 

[An Buachaillín Bán]

As mentioned it's done through a CTU (central test unit) and contactors rather than key switches.

I.S. 3217 are the Emergency Lighting Rules which need to be complied with - it's not BS 5266. It's done a bit differently.

Hi Risteard,

Would you be able to explain to me how the wiring for the above is done? I see contactors in place for emergency lighting in some of the sites I cover, even though there might only be 4 NM emergency fittings. Do I have to install a contactor? Or if there are only a few EML, could I not come from my control mcb, to my CTU and then out to my emergency lights?
Thanks

 

[davesparks]

I'm a little confused why you think you need a contactor to switch an 80W load (20 x 4 watts ) that draws 0.34 amps

You do when the emergency lights are connected to different circuits but a single test switch in a central location.