What happens in the fittings of em lights.

[Andy 7671]

Hmmm...how to explain this ...

L1 ....Permanent feed via key switch to battery pack. (OK to termination point which leads to battery)

L2.....Switchline to lighting


Now I flick the keyswitch which opens circuit and light is by battery power.

What about L2,...? is there a coil in the fitting which collapses, preventing power reaching lights..?


Any knowledge greatfully received....

 

[rich.250]

Isn't the switch live run through the keys witch in the first place?? So isolating it by switching it to test???

 

[Guitarist]

The keyswitch is there to simulate a power cut, ie. kill the permanent live.

 

[Andy 7671]

Running the swline through keyswitch would then turn all lights off, standard and emergency.

A more practical method I grant you, but what if you wanted all the standards to be lit...?

 

[Guitarist]

The keyswitch will only kill the perm live to the emergency light which is being tested. I would be surprised if every light in an area with no natural light was a maintained EM.

 

[Andy 7671]

The keyswitch is there to simulate a power cut, ie. kill the permanent live.

Yeah but youve still got L2 which is feeding the lights, L1 the keyswitch, is charging the battery pack.

Why have I got the feeling Im missing something...?

 

[Andy 7671]

The keyswitch will only kill the perm live to the emergency light which is being tested. I would be surprised if every light in an area with no natural light was a maintained EM.

Yeah I get that, thanks, but Ive still got a switchline, L2 which hasnt been isolated, supplying power to the fitting, so ...so...so...this is the part I dont get, there must be something isolating L2 somewhere ...but where..?

 

[ezzzekiel]

Depends if feed for switch comes from top (perm) or bottom of ks and l2 is via normal switch either on or off

 

[RogertheBodger]

L1 feeds the battery charger in the fitting, L2 switches it on and off, all done through the magic of a Pcb.

Which is where my knowledge ends - you now need an electronics engineer.

Me - I just take it for granted.

 

[jumpin jax]

You can wire the emergency lights in 2 ways
1 so you kill total power to the whole local lighting circuit hence turning emergency mode on or
2 so you kill permanent live supply which keeps normal lighting on except the emergency ones where the emergency mode comes on in maintained , or turns emergency lamps on in non-maintained
clear as mud:frown:

 

[Andy 7671]

Depends if feed for switch comes from top (perm) or bottom of ks and l2 is via normal switch either on or off

Thanks, thats highlighted a gap in my knowledge, thought the ks was just in/out.

Still aint getting it though....

If all the standards are lit then how am I testing em fittings when there is still a supply to L2.

I never said I was clever, never ever said I was clever, thorough yes but capable of instant insight...sorry... Im trying

 

[Andy 7671]

L1 feeds the battery charger in the fitting, L2 switches it on and off, all done through the magic of a Pcb.

Which is where my knowledge ends - you now need an electronics engineer.

Me - I just take it for granted.

Yeah, thanks thats great.

So..."When isolating L1, the PCB automatically isolates L2 and puts fitting in battery back up mode"...

thanks

 

[ezzzekiel]

If all lights are switched on the opening the kill switch will leave all lights on but the emergency fittings will turn off except the em light (if they're 6x6 four tube fittings for example) unless the ks has been wired to kill power to all lights.

 

[Andy 7671]

You can wire the emergency lights in 2 ways
1 so you kill total power to the whole local lighting circuit hence turning emergency mode on or
2 so you kill permanent live supply which keeps normal lighting on except the emergency ones where the emergency mode comes on in maintained , or turns emergency lamps on in non-maintained
clear as mud:frown:

So..."Non maintained ems are normally off and ONLY come on when power goes off"

Thats right isnt it, please tell me Im right.

 

[RogertheBodger]

Got it in 1