Staircase Timer on a UPS Supply

[sammut93]

Hi All, Thankyou in advance for your help

I have a block of 5 stories with a staircase timer already installed in a 3 wire connection setup.
I am trying to setup a UPS to supply the lights in the common areas so that it acts as an Emergency Lighting setup - when power fails the lights still go on-

the trouble is as follows

AEG staircase timer. works fine on Mains., If I simulate power failure by shutting off mains while the timer is going the lights keep on till the timer shuts off. however a soon as the lights go off for some reason the timer won't work anymore.

UPS output is standard 230V 50Hz

I tried replacing the timer with another brand (probably chinese make)
but irrelevant of UPS or Mains Power it keeps going on, wont turn off.

any ideas on why the AEG timer won't work on UPS are much appreciated.

Thankyou

 

[James]

Electronic timers like that won’t like the modified sine wave from a cheep ups.
a pure sine wave unit is probably going to be required.
or you could put up an emergency light.

 

[Simon47]

Probably simpler to put up self contained emergency lights. Either that, or ditch the UPS, use a DC circuit, and run it off a battery that's floated with a suitable charger.
But the biggie is - who will be certifying that this setup complies with all the relevant rules & regulations ? If you use self contained luminaires (which you may well be able to have doing normal lighting as well as emergency - depends on locations) then you point to the guidance as to where they should be, point to the various approvals on the units, job done. If you DIY a solution, then you are opening yourself up to a whole world of potential problems ...
Imagine the worst happens and there's an incident. People need to get out. They fall down the stairs because the lights don't work (properly or at all). Charred bodies later found in stairwell. I know that's rather extreme, and a bit grim, but "---- happens" - and then the questions start, and when a survivor says the lights didn't work, all eyes are on your and you now have to demonstrate why your DIY system was no less safe than it would have been using off the shelf stuff.
From the way your post is worded, it sounds like you do not have the knowledge to be able to say with any authority that you were suitably skilled and qualified to design the system - so in extreme, potential for a spell behind bars, as if having people's deaths on your hands isn't enough.