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# Electricity: effect-sensitive device...?

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Is there any way to create an effect-sensitive device? What I mean with this is that a device should be able to perform a specified task when a specific energy e.g. 3 kJ has been used during a specific time e.g. 5 min. I won't build the actual device, but I wonder if there is any chance that it could be built... and how? You don't have to know exactly how, just give me some ideas... don't know what to google for =)

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I don't know what you're leading into with the specification of Joules/minutes, but....

This is what I'd call an "effect-sensitive device."

Theremin - Wikipedia, the free encyclopedia

Minimum Theremin Kit Schematic

...and a fun "effect" too.

~ :)

p.s. ...or maybe you are thinking of some other effect-sensitivity?

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You mean you want to measure how much electricity has been used? If so, every house has one, and you can get a small one at the store for about 30 \$.

If I get it right you want to do something when so much power goes trough. That could be a little tricky with off the shelf devices.

Wattmeter - Wikipedia, the free encyclopedia

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Well I feel as if we are getting on the right track now.... I know what a wattmeter is, so I believe that I was a little diffuse in my explanation. What I really want to do is to have the electricity flow through a device, just like it does with the wattmeter. Then I would like to use this device to cut of the current, when the electrical circuit connected to my device (e.g. television) has used an energy, say 3 kJ for 5 min (e.g. stand-by in 5 min), then the circuit is opened, and the TV is shut down. I have no idea how to do this, and as I said, I am only interested in the theory behind not to actually build one device on my own. I don't know if this is possible to build, but it would be cool if it did... the technology of the wattmeter could probably help... thx for the link and for further links on the issue :). (I hope that the better explanation helped...)

Thanks for the help again... I appreciate it :)

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hmm, 3kJ is about 0.8 watt hours, or about half a minute of watching TV. :) Thats if its using 100 wats.

Well it would require getting an analog wattmeter and rigging it. Well connecting one wire to the pointer and the other one to where it would be when that much electricity has been used. So when the two would meet, it would turn the switch. Just like in the old clock bomb. :)

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Thanks for the help... I believe that I will manage now =). So I will simply have a wattmeter and a "relay/timer-something" and put them together to be able to create something that stops the circiut to a TV when it has been in stand-by for e.g. 5 min... thanks alot for the help!!!!

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hmm, so you want to kill the power when the device has been on standby more than 5 minutes... Well I was thinking you want to kill it when it uses that amount of power no matter whether it is used or not.

If you want to make a circuit that would kill the power to the tv after it has been shut off, it would be better to wire the wattmeter so that when usage falls under 10 watts, the timer is engaged...

Or you could just have a manual electric switch, or a remote one.

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yepp... something in that way was what I was thinking about.... Thanks for the help Roadam!

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