Switching ideas

[Guest125]

Peps,

So, I went to look at a job today at London Waterloo Station. They have a peak hour only link corridor that runs from the underground to the overground concourse.

Within this area there are about 250 twin 49w T5 fittings. Half of which are emergency. Now these fittings are wired with only a permanent supply. So the lights are on 24/7. There is no natural light at all.

NR want us to alter the switching arrangements so that the lights can be switched off when the corridor is closed but still maintaining the emergency feed.

Now I am thinking new single core cable (SWA or PVC/PVC) to supply all the lights with a switched feed. Then install ceiling 360 deg PIRs at suitable intervals to turn the lights on when required (via contactors etc...).

Can anyone think of a better way of achieving the same result?

 

[telectrix]

Simpler to stick the feed on a timer using contactors to power the lights)

 

[Guest125]

Simpler to stick the feed on a timer using contactors to power the lights)

But then the emergency batteries will discharge completely and if the station went into evac then there would be no lighting at all.

 

[telectrix]

Oops. Missed the em bit. My bad.

 

[Guest125]

Oops. Missed the em bit. My bad.

No point back tracking now!!!!!!!!

 

[davesparks]

How are they wired at the moment? if its conduit or trunking then its just a single to pull in unless i'm missing something

 

[ipf]

And how are they switched at present...?...isolation!

 

[Darkwood]

Extra wire and as above just a timer... no frequent switching of T5's reducing lamp life to worry about and/or failing PIR's ...plus significantly less wiring than PIR control...so no brainer !

 

[rapparee]

If you do go down the pir route make sure it lasts at least 20 mins to try and preserve lamp life

 

[Guest125]

Unsure of containment as of yet due to metal ceiling tiles in the way. Suspect tray and SWA/FP200.

The issue I see with not putting sensors in is that if the corridor is opened in an emergency outside of these times then they will be in darkness. There are multiple entrances to the corridor also so key switches are out of the question.

They em are currently only switched off by DP key switches in the elec cupboard.

 

[Guest125]

 

[Guest125]

 

[Darkwood]

Try not to trickle info .... the more you tell us the better response we can give... you never mentioned about it maybe opened unexpectedly .... Is this corridor locked of with barrier gates... you could run a set of limits to the gates and if opened the lights will over-ride.

Someone must be in charge to open up out of hours they could just advance the timer setting?

 

[TJ Anderson]

You could put timer in parallel with PIR's, then you could maintain it during set hours (and prolong lamp life). It would then go to PIR control outside set hours which would cover when opened unexpectedly.

 

[marc8]

Ukesrail
why not offer an alternative view fit LED lights, with emergency on some & microwave sensor & that can dim down to 10% when not in use then no need for more cables & energy saving at same time.
Just a thought