Lighting time delay after switching off

[mdj1]

Hi All.

I can find plenty of switches that once turned on turn off after a certain amount of time but what I'm looking for is something that once turned on stays on, but when turned off the light stays on for x minutes.

I have an outside light at work and I want to be able to turn it off inside, but it stay on for a few minutes whilst I go outside and lock up.

Any suggestions.

 

[mdj1]

Found a company in canada, no good for me though.

http://www.broan.ca/product-detail.asp?ProductID=100539

 

[nickjb]

Could you use a switch for a bathroom fan? They do that kind of switching. Obviously you'll need to check the power rating.

 

[bernardgreen]

Put a pneumatic timed switch in parallel with the existing switch.

When you leave press the pneumatic timed switch and then turn the existing switch off.

Or turn the existing switch off ( and be sure the light is off ) then press the pneumatically timed switch to bring it back on while you lock up.

Only disadvantage with the second method is the OFF then ON of the hot lamp may shorten the life of the lamp.

 

[mdj1]

Seems like a lot of hastle for such a simple thing.

You would have thought that this sort of thing would be popular.

If I have to go with the pnumatic option, how would this be wired?

 

[Spark123]

As Bernard said - in parallel with the existing switch
If you don't understand how to do this you need an electrician to do it for you - which is probably a good idea given it is a place of work.

 

[ericmark]

I would agree seems in US they don't have timers built into fans but they are built into switches. These may do the job also these may also work. And these may also be configured to do what you want.

But normal method is to use a contractor with pneumatic delay and it would need a box to mount it in and really bernardgreen idea of a pneumatic timed switch in parallel with the existing switch is likely easiest and cheapest.

 

[SUNRAY]

Hi All.

I can find plenty of switches that once turned on turn off after a certain amount of time but what I'm looking for is something that once turned on stays on, but when turned off the light stays on for x minutes.

I have an outside light at work and I want to be able to turn it off inside, but it stay on for a few minutes whilst I go outside and lock up.

Any suggestions.

http://www.nuaire.co.uk/IandM/671106.pdf

 

[mdj1]

Just what I need You are a star!

£66 direct, will check with Eddy's

 

[SUNRAY]

Just what I need You are a star!

£66 direct, will check with Eddy's

If you use wholesalers or RS look for 'run on timer'at around £30 but will need enclosure and mounting arrangements and stuffing glands...,

they are usually used for things like boiler primary pumps to ensure a large boiler cools a little or a flue fan to ensure its clear of gasses after the burner stops.