Where to find a dedicated timer?

Greetings,

I am looking a timer where I set the length of time, then push a button and the electric flow for that amount of time and shuts off.

I don't want timers that turn on at a set time and off at a set time. That is out of the question.

I want a timer where you set the length, then push a button. Every time you push the button the timers is set for that length of time.

W. Kirk Crawford

Reply to
W. Kirk Crawford
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I need to explain more, this timer does not draw power until the button is pushed.

W. Kirk Crawford Tularosa, New Mexico

the electric flow for that amount of time and shuts

out of the question.

push the button the timers is set for that length of

Reply to
W. Kirk Crawford

Sounds as though you need something run by clockwork ;-)

Reply to
charles

Strange to relate, I have two sat on my drawing room table as I write.

One looks like a relay but contains a synchronous motor, a gearbox and an adjuster calibrated 0-10. Push a button and it runs for the set time up to ten seconds and then stops.

Another is much larger and has a rotary scale going from 0-100. You turn a knob to the desired time and, when you push a button, a relay operates and the knob rotates back to zero, when the relay de-activates. The knob scale actually has an outer ring that can set the time from 0-100 mS,

0-1 S, 0-10 S, 0-100 S, 0 -1000 S and 0-10000 S - by changing gearbox ratios.

I only mention those because I am trying to find a use for them and, if you lived anywhere near me in darkest Devon UK, you could just have come and collected one for free.. They came out of equipment that I had stripped down.

I was going to use the big one in a box supplying power to a socket for my electric clothes iron - as I am for ever leaving the thing on...

However, I digress. I think the thing you need is a "darkroom timer".

Reply to
Palindrome

electric flow for that amount of time and shuts off.

out of the question.

push the button the timers is set for that length of

This one is clock based, but you could still set it for a given span and it would indeed work.

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This one does what you want, but is not automated. You have to stop dialing at the appropriate location.

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Reply to
ChairmanOfTheBored

You might try looking here: >

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This timer is used in irrigation systems and might do what you want. It takes up some space though. This company has a bunch of timers: >
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They don't sell retail but you could get an idea what's available at least.

Dean

Reply to
Dean Hoffman

electric flow for that amount of time and shuts off.

out of the question.

push the button the timers is set for that length of

Intermatic makes one that runs about 10 minutes per switch operation. I have one on my bathroom fan. The other easy option is a spring would timer. If you want to make something look at the circuits they cobble up from a 4060 CMOS counter and a relay, solid state or mechanical. This guy has some samples of what you can do

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Reply to
gfretwell

To make his own...

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Reply to
ChairmanOfTheBored

the electric flow for that amount of time and shuts off.

out of the question.

push the button the timers is set for that length of

The also make a 12Hr version. Light switch replacement type configuration.

Reply to
ChairmanOfTheBored

and the electric flow for that amount of time and shuts

That is out of the question.

you push the button the timers is set for that length of

solid state time delay relay.

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Reply to
Tim Perry

Nice!

Apart from the rain we spent a very pleasant week in Chagford earlier this year :-)

Reply to
Stuart

The big problem with Chagford is that it is a sod to get to in a bus in mid-Summer...especially if you are the driver. Still, the look on some people's faces when they round a corner and find a hedge-to-hedge bus coming at them is something to treasure.

There is a little spot not too far from there that really is an almost entirely undiscovered wonder. A public path starts by going through a very uninspiring farmyard. A short walk later, you are beside a little river tumbling down a hidden valley, complete with deep pool to go swimming in. I've been going there for years and never seen a soul, other than from the farm...

Reply to
Palindrome

Come on Sue! If you want REAL excitement in a bus, let the driver go off the side of a mountain between Ft Greely and Fairbanks, Alaska while the passengers scream for their lives. I missed that ride by two weeks, in the mid '70s. Sam bus, same route, and same driver, with friends of mine aboard. They were all SURE they were going to die. :(

It dropped a couple hundred feet, and was caught by a large tree. A few ended up in the hospital, but no one died.

Reply to
Michael A. Terrell

electric flow for that amount of time and shuts off.

out of the question.

push the button the timers is set for that length of

Depends on your specific application.

If you specified operating volts, AC or DC, current, accuracy needed, etc. you might receive a specific answer.

For low accuracy on low voltage DC I use a simple power FET transistor with a capacitor/resistor on the gate, a relay, and a SPST switch. The resistor can be a variable that you adjust to set the time. If the load is DC and not harmed by a slow turnoff, the FET can drive it directly. If brewing your own, look at the old LM555 timer circuits for more accuracy and a definate snap action.

There are 2-inch square timer blocks with a series of small switches to set the time, but they are specific to a voltage and load current. Bill Kaszeta Photovoltaic Resources Int'l Tempe Arizona USA snipped-for-privacy@pvri-removethis.biz

Reply to
Bill Kaszeta / Photovoltaic Resources

the electric flow for that amount of time and shuts

Google 'Time Delay Drop Out'.

You will have to check out the specs on each relay. Some 'consume' a small amount of power while waiting for the start command even though their controlled contacts are open (pass no current) until the period is initiated. You will have to define exactly what you mean by the timer not 'drawing power'.

Reply to
Paul Hovnanian P.E.

the electric flow for that amount of time and shuts

If you just want a one shot, the simplest way is a capacitor discharging across a darlington with a pot to fine tune the discharge time. If you are holding up a relay through a normally open contact you can drive any load the relay can handle. Dropped out, it is an open circuit

Reply to
gfretwell

Doesn't a simple, octal based TDOD timer fill the bill here? That and a momentary switch?

Reply to
Long Ranger

The Devon, Cornish and a lot of Welsh roads are good for getting in a lot of reversing practice ! :-)

Not too bad in a car or an elderly Espace like mine but.....

Sounds nice. I'm afraid the weather did dampen our enthusiasm a little for walking. We did one walk around Buckfast, mostly through woods, following up with a visit to the Abbey and even when in the open the rain wasn't too bad that day. The Friday before we left was dry and we managed to get up on the moors near Princetown.

We will probably be heading down in that direction again next year but whether to Chagford or somewhere else has yet to be decided.

Reply to
Stuart

The Devon, Cornish and a lot of Welsh roads are good for getting in a lot of reversing practice ! :-)

Not too bad in a car or an elderly Espace like mine but.....

Sounds nice. I'm afraid the weather did dampen our enthusiasm a little for walking. We did one walk around Buckfast, mostly through woods, following up with a visit to the Abbey and even when in the open the rain wasn't too bad that day. The Friday before we left was dry and we managed to get up on the moors near Princetown.

We will probably be heading down in that direction again next year but whether to Chagford or somewhere else has yet to be decided.

BTW.

Does this little group of children here /ever/ stop hurling obscenities at each other?

Reply to
Stuart

Thankyou.

I will place in my address book

Reply to
Stuart

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