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Richard III
10-22-2008, 12:11 AM
I was wondering how I could make a fog machien produce for for 5-10 secs or so by an infrared Tripwire. when someone walks throw the Infrared Beam it will tell the fog machien for 5-10secs to produce fog. I would need some help in designing the circirt board but i am pretty good at electronics. I know that when you cross two of the wires on the fog machien it will produce smoke, so maybe somekind of relay or so.

Thanks Ricky

BuzzKill
10-22-2008, 12:53 AM
You dont have to re-invent the wheel here unless you want to. Look at some motion sensing lights at your local home depot and see if the "ON" cycle can be dialed down to the 10 seconds you want. Then wire a 120v relay up to the socket and then wire the contacts to the switch in the fog machine remote and it will "push" the fog machine button for you.

There are also a bajillion 555 timer based circuits that could do what you want if you really want to build something from scratch.

Mufassa
10-22-2008, 01:51 PM
or just put the light in the "Test" mode.. I think they all have it.. and it trips for about your 10 sec or so.. I think.. YMMV but might be viable.

--Greg

kostyun
10-22-2008, 01:59 PM
I think i agree with buzz on this on - motion sensor is the quickest/fastest way

Richard III
10-22-2008, 02:32 PM
Ok Thanks guys,

Ok so I would need the motion sensor to close a "swtich" allowing power from a 12V power source to close the relay and on the other side the relay would close the 120v side allowing the fog machien to produce smoke.

Would this work for the relay:
http://www.radioshack.com/sm-125vac-10a-dpdt-plug-in-relay--pi-2049721.html
or
http://www.radioshack.com/product/index.jsp?productId=2062482&cp=&sr=1&kw=125vac+relay&origkw=125VAC+relay&parentPage=search

to power the low voltage side of the relay would i use a little 12v DC power adapter or what would i use. I'll draw a littlw schematic of what i think i need to have.

Richard III
10-22-2008, 05:06 PM
wait so if the motion sensor uses 120VAC then I wouldnt even need a Relay just a motion sensor and a power switch. Right??? or am I all wrong?

Josh
10-22-2008, 05:52 PM
you are correct on the last post Richard. You can buy replacment motion sendors at wal-mart for around $8 just wire it up, it is 120v ready

BuzzKill
10-22-2008, 05:56 PM
You still need the relay.. just a 120V relay. The coil side is powered from the 120 volts in the motion sensor light. You can either tear apart the socket, or get one of those little screw in adapters that turns the light socket into a plug. Then the NO (normaly open) "dry contact" side of the relay goes to the 2 sides of the switch in the fog machine remote. When the motion turns on the light socket, the relay coil is energized, the contacts close, and you "push" the button for the fog machine.

http://www.radioshack.com/product/index.jsp?productId=2049721&cp=&sr=1&kw=relay&origkw=relay&parentPage=search

They have a socket for it too.

Richard III
10-22-2008, 06:04 PM
You still need the relay.. just a 120V relay. The coil side is powered from the 120 volts in the motion sensor light. You can either tear apart the socket, or get one of those little screw in adapters that turns the light socket into a plug. Then the NO (normaly open) "dry contact" side of the relay goes to the 2 sides of the switch in the fog machine remote. When the motion turns on the light socket, the relay coil is energized, the contacts close, and you "push" the button for the fog machine.

Except do i really need the relay if the contacts on the fog machine are 120 VAC and when these are closed the machien creates fog.???
and wouldnt this have to have both sides of the relay be 120VAC???

I may not be making anysense-so if you could explian waht you mean.

Or is it that the motion sensor must be wired to a 120 volt source as i was thinking the fog machien might be the sorce???

BuzzKill
10-22-2008, 06:08 PM
Yes. Otherwise instead of using the relay to "push" the button with the relay contacts, you would be feeding the 120 volts from the motion sensor into the fog machine through the remote switch. That would be bad.

Richard III
10-22-2008, 06:10 PM
Yes. Otherwise instead of using the relay to "push" the button with the relay contacts, you would be feeding the 120 volts from the motion sensor into the fog machine through the remote switch. That would be bad.

O ok so I definatly would need the relay becuase the motin sensor will have to be power by a outlet or a power cord.

BuzzKill
10-22-2008, 06:22 PM
O ok so I definatly would need the relay becuase the motin sensor will have to be power by a outlet or a power cord.

Correct! Happy fogging!

Richard III
10-24-2008, 12:43 AM
Hey thanks Every one especially Buzz. It works amazing - Just how I wanted it to. I ran into one problem where i wired a light bulb in serise with the sensor causing the sensor to not have enough power and so i fixed that by putting the light in parrallel. When you walk past the sensor the fog shoots out at you and i am planning to use this in a haunted house. Thanks Agian Everyone

Ill post pics soon!
Ricky