Switch on a light box for 45 seconds

I work at a museum and would like to hook-up a light box to some kind
of switch that would have the box stay on for about 45 seconds and go
off. Any ideas?
Thanks

 

[Dan Mills]

mcronin111@yahoo.com wrote:

I work at a museum and would like to hook-up a light box to some kind
of switch that would have the box stay on for about 45 seconds and go
off. Any ideas?
Thanks

Over here you can get light switches that do exactly this (intended for use
on staircases) maybe possible?

The other thought I have is that a photographic enlarger timer does what you
need.

Regards, Dan.

 

[Dennis Mchenney]

Might also look into using a motion detector wall switch, aimed as would
need to wave hand in a space to activate it. Not sure if can get one
with the exact time period you want or be adjustable to that.

mcronin111@yahoo.com wrote:

I work at a museum and would like to hook-up a light box to some kind
of switch that would have the box stay on for about 45 seconds and go
off. Any ideas?
Thanks

 

[Chris]

mcronin111@yahoo.com wrote:

I work at a museum and would like to hook-up a light box to some kind
of switch that would have the box stay on for about 45 seconds and go
off. Any ideas?
Thanks

If you'd like a store bought solution, stop by a camera store and look
at their darkroom timers. Gra-Lab is a good source for this in the
States.

If you'd like something a little less expensive, get a 12VDC wall wart
and the Velleman MK-111 Interval Timer kit. It uses a 555 and a relay
to give you exactly what you need. It includes circuit board and all
components except the wall wart. The relay will switch up to 3 amps at
120VAC.

Questions of this type usually receive a better response on
sci.electronics.basics.

Good luck
Chris

 

[Alan Turner]

On Sat, 19 Feb 2005 16:37:22 -0800, mcronin111 wrote:

I work at a museum and would like to hook-up a light box to some kind
of switch that would have the box stay on for about 45 seconds and go
off. Any ideas?
Thanks

I'd go to a hardware store and ask for one of those timers which runs a
bathroom extractor fan for a fixed period after the light is turned off.

An off-the-shelf solution will almost certainly be cheaper than a
homebuilt one once you factor in the cost of putting it in a box,
providing a power supply for the electronics, etc.

Alan

--
Alan R. Turner | Live never to be ashamed of anything you do or say.
To reply by email, remove Mr Blobby.

 

[Terry Pinnell]

mcronin111@yahoo.com wrote:

I work at a museum and would like to hook-up a light box to some kind
of switch that would have the box stay on for about 45 seconds and go
off. Any ideas?
Thanks

It's not clear which of these you want:

a) a ready-made, shop-bought circuit just requiring careful
connection (by someone qualified, possibly yourself, as presumably the
box is mains-powered)

b) a circuit you can build

If the former, then you've had several recommendations.

If the latter, then you could base it on these circuits:
http://www.terrypin.dial.pipex.com/Images/555MonoByPU.gif
http://www.terrypin.dial.pipex.com/Images/555OneShot.gif
http://www.terrypin.dial.pipex.com/Images/555Mono+Driver.gif

with suitable Rt and Ct. For example, combinations such as
500k 82uF; 1M 39uF; 2.7M 15uF etc
give the required delay.

You haven't specified power supplies, or switch type, so adapt as
necessary.

--
Terry Pinnell
Hobbyist, West Sussex, UK

 

[Fred Bloggs]

Chris wrote:

mcronin111@yahoo.com wrote:

I work at a museum and would like to hook-up a light box to some kind
of switch that would have the box stay on for about 45 seconds and go
off. Any ideas?
Thanks


If you'd like a store bought solution, stop by a camera store and look
at their darkroom timers. Gra-Lab is a good source for this in the
States.

If you'd like something a little less expensive,...

I'll say- all that GraLab stuff is over-priced glitz, even a foot switch
is $60- any kind of electronic timer $200.

 

[Keith Wootten]

In message <1108859842.583361.279750@c13g2000cwb.googlegroups.com>,
mcronin111@yahoo.com writes

I work at a museum and would like to hook-up a light box to some kind
of switch that would have the box stay on for about 45 seconds and go
off. Any ideas?
Thanks

Rswww.com part number 490-194 for example.

Cheers
--
Keith Wootten

 

[Spehro Pefhany]

On Sun, 20 Feb 2005 17:26:20 GMT, the renowned Fred Bloggs
<nospam@nospam.com> wrote:

Chris wrote:
mcronin111@yahoo.com wrote:

I work at a museum and would like to hook-up a light box to some kind
of switch that would have the box stay on for about 45 seconds and go
off. Any ideas?
Thanks


If you'd like a store bought solution, stop by a camera store and look
at their darkroom timers. Gra-Lab is a good source for this in the
States.

If you'd like something a little less expensive,...

I'll say- all that GraLab stuff is over-priced glitz, even a foot switch
is $60- any kind of electronic timer $200.

They're probably only making 10% of the quantity per year that they
used to make. Maybe less with all the used stuff floating around.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com