Author Topic: Digital Timer  (Read 1394 times)

Offline Logoman

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Digital Timer
« on: June 16, 2014, 11:29:39 AM »
I am looking for a Digital Timer for my exposure unit. All it needs to do is turn the light on and off. Any suggestions?


Offline larryk

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Re: Digital Timer
« Reply #1 on: June 16, 2014, 11:48:09 AM »
Have you tried Grainger?

Offline screenprintguy

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Offline jvanick

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Offline IntegrityShirts

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Re: Digital Timer
« Reply #4 on: June 16, 2014, 03:26:33 PM »
I'm using this one on my DIY LED setup that is currently still being tested

http://www.amazon.com/gp/product/B00DSQQSAE/ref=oh_details_o01_s00_i00?ie=UTF8&psc=1

Switches 30amp 12v relays in my case. Also a dual timer, so when you hit start you can have a countdown timer for vacuum, then the switch kicks the lights on for a set time.

Offline Sbrem

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Re: Digital Timer
« Reply #5 on: June 16, 2014, 04:13:54 PM »
Maybe an old Gralab darkroom time, you'll need to be sure of the max time, so you don't have to turn it on more than once to make an exposure...

Steve
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Offline tonypep

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Re: Digital Timer
« Reply #6 on: June 17, 2014, 08:34:54 AM »
Not sure what model you may have but remember a timer measures seconds, not light units, which means you will most likely need to adjust over time as the bulb(s) lose intensity. Also sufficient vacuum pressure should be achieved before the light source is activated to avoid undercutting. Not optimum but better than not having anything at all.

Offline balloonguy

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Re: Digital Timer
« Reply #7 on: June 17, 2014, 09:18:55 AM »
I'm using this one on my DIY LED setup that is currently still being tested

http://www.amazon.com/gp/product/B00DSQQSAE/ref=oh_details_o01_s00_i00?ie=UTF8&psc=1

Switches 30amp 12v relays in my case. Also a dual timer, so when you hit start you can have a countdown timer for vacuum, then the switch kicks the lights on for a set time.

Would you share any pics/info you have on this?
Thanks,
matt
When you dig grave will you make it shallow so that I can feel the rain?

Offline balloonguy

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When you dig grave will you make it shallow so that I can feel the rain?

Offline ScreenFoo

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Re: Digital Timer
« Reply #9 on: June 17, 2014, 02:38:02 PM »
I bought a lot of AL 975 integrators last year, if you're in the US and interested in grabbing one, shoot me a PM.

Still need a relay box, but you could also grab a photocell and use it as a proper integrator...

Offline IntegrityShirts

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Re: Digital Timer
« Reply #10 on: June 17, 2014, 03:15:43 PM »
I bought a lot of AL 975 integrators last year, if you're in the US and interested in grabbing one, shoot me a PM.

Still need a relay box, but you could also grab a photocell and use it as a proper integrator...

I have an extra AL 975 that I wanted to use for this LED project. I probed the serial connector with a multimeter on every pin combination I could imagine while the timer was switching from off to on and couldn't find a signal usable to switch a relay. I gave up and bought that cheapie timer off Amazon.  :(

Matt, I'm going to make a thread in the DIY  section for this ugly thing I cobbled together.

Offline ScreenFoo

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Re: Digital Timer
« Reply #11 on: June 17, 2014, 05:24:35 PM »
Yeah, logic level is .7 volts, need to step it up at least a few volts if you're the one making the box.  ;)