Any good halloween ideas?

Can I use this relay:

http://www.radioshack.com/sm-12vdc-1a-spdt...pi-2062481.html

pRS1C-2160390_rshalt1_dt.jpg
 
Referencing (and and cross-posting to) your topic on the Smarthome forum:

http://www.techmall.com/topic.asp?TOPIC_ID...amp;whichpage=2

The same thing as described for the Garage Door Opener will work here; just substitute the garage door button for the "smoke" button in the picture. One thing to take note of on the fogger though is that the voltages will be higher than the garage door opener. Make sure when you get a relay, that the CONTACTS are rated for 120 Volts and probably at least 5 amps. The COIL voltage will still need to be low so it matches the wall wart voltage. Other than that, everything else will be the same. You can actually use the 120V Contacts for the GDO too, it won't hurt anything. It would be kinda like using a big light switch to turn on a flash light bulb. Overkill, but it would work.

You can probably find a relay that will fit in the remote case in that empty space below the switch. If you can, then you can simply connect the NORMALLY OPEN (N.O.) contacts on the switch in parallel to the existing switch wires (just like you would on the GDO button). Then just connect two wires to the relay coil and run those out of the remote and to your wall wart. Plug the wall wart into an appliance module/appliance link and you're ready to go.

You could also get rid of the switch altogether and just tie the wires that were going to the switch to the N.O. contact on the relay. The basic premise here is that the relay is a device that uses a small voltage on one side (wall wart) to switch on/off a larger voltage (fogger) on the other while keeping the two voltages isolated from each other.

Here is a nice little article that explains how a relay works.
http://home.howstuffworks.com/relay.htm

Be EXTREMELY CAREFUL here as your working with voltages that can kill you. If you are unsure at all about how to proceed, don't. Get help from an electrician or friend/neighbor that has electrical knowledge.


HTH

Terry
 
Referencing (and and cross-posting to) your topic on the Smarthome forum:

http://www.techmall.com/topic.asp?TOPIC_ID...amp;whichpage=2

The same thing as described for the Garage Door Opener will work here; just substitute the garage door button for the "smoke" button in the picture. One thing to take note of on the fogger though is that the voltages will be higher than the garage door opener. Make sure when you get a relay, that the CONTACTS are rated for 120 Volts and probably at least 5 amps. The COIL voltage will still need to be low so it matches the wall wart voltage. Other than that, everything else will be the same. You can actually use the 120V Contacts for the GDO too, it won't hurt anything. It would be kinda like using a big light switch to turn on a flash light bulb. Overkill, but it would work.

You can probably find a relay that will fit in the remote case in that empty space below the switch. If you can, then you can simply connect the NORMALLY OPEN (N.O.) contacts on the switch in parallel to the existing switch wires (just like you would on the GDO button). Then just connect two wires to the relay coil and run those out of the remote and to your wall wart. Plug the wall wart into an appliance module/appliance link and you're ready to go.

You could also get rid of the switch altogether and just tie the wires that were going to the switch to the N.O. contact on the relay. The basic premise here is that the relay is a device that uses a small voltage on one side (wall wart) to switch on/off a larger voltage (fogger) on the other while keeping the two voltages isolated from each other.

Here is a nice little article that explains how a relay works.
http://home.howstuffworks.com/relay.htm

Be EXTREMELY CAREFUL here as your working with voltages that can kill you. If you are unsure at all about how to proceed, don't. Get help from an electrician or friend/neighbor that has electrical knowledge.


HTH

Terry


Terry,

Can I use the above listed Radioshack relay for this project?

Thanks,
Rich
 
Others may have some alternate suggestions, I'd get a feel for everyone's opinion before jumping in. I don't have a fogger yet :) so I don't have any experience with the actual electronics involved, however...

I wouldn't use that relay, the amperage rating is the amount of current that can flow through the contacts (1 Amp on that relay), not how much current the coil requires to operate. I think it's too small for this. Look at this one instead:

http://www.radioshack.com/product/index.js...rentPage=family

The contacts on this one are rated for 10 Amps at 125Volts which should be more than enough for your fogger. To be sure, you can look at the switch. It probably has the specs printed on the side and as long as the current is under 10 amps this relay should work.

On relays, be careful not to confuse the voltage and current that the coil requires with the voltage and current that the relay contacts can switch.

As an example:

THE "INPUT" SIDE OF THE RELAY
The relay above requires 12 Volts DC and 30miliamps to operate. That’s what it takes to make it switch on/off. You mentioned that your wall wart can deliver 1000 milliamps (1 amp) so that is more than enough as long as the wall wart output voltage is 12 volts.

The voltage needs to match, and the supplier (wall wart) needs to capable of supplying at least as much current as the consumer (relay coil) needs. If it can supply more, that's ok. The consumer will only use what it needs. In this example your wall wart (gives 1000mA) could supply up to 33 relays (takes 30ma) with enough current.

Never supply more VOLTAGE than the relay needs though, if you do the best outcome is a shortened relay life, the worst case is a fire from the coil overheating and shorting out

THE "OUTPUT" SIDE OF THE RELAY
The relay above has contacts that are rated at 125Volts at 10 Amps. That's enough to switch on/off 12 100 watt light bulbs at maximum power. A 10 amp capacity may be overkill for the fogger, but a bigger "switch" never hurts. If you are only switching 5 amps of current on/off then theoretically the relay will never see more than half of its maximum load.

Think of it like a truck bed. You may be able to carry 3500 pounds of material in your bed, but it will also work fine for the 5 bags of mulch you need. You however would not want to balance those 5 bags of mulch on a motorcycle as it wasn't designed for that type of load.

DISCLAIMER:
I can't say enough to be careful working with these voltages, it's more than enough to kill you. If you are uncomfortable or unsure about exactly what to do, then don't do it. As a mater of fact, I'm recommending that you don't do it. I'm not a pro by any means so don't take what I'm suggesting as the gospel. It will work however as I and others use this method frequently with success (I have also let the smoke out of several pieces of electronics in my life.) Bottom line; you can't be too careful.


HTH, be sure to post what you end up doing.


Terry
 
Terry,

Thanks for the excellent instructions. Everything works (Insteon mode & also the manual push button mode). Works 100%

Thanks,
Rich
 
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