View Full Version : Control lights

01-13-2006, 03:31 AM
I need to know what kind of setup would be needed to control a standard 110V light bulb. The idea is to be able to remote control the light. I have got the RF part down but I am having trouble with how to setup the board to interface the light bulb. I am struggling with the idea of how a relay coming off my board would control that many volts? Anyone know of a website or can explain a little about how to set this up? I am hoping to get by with a solid state relay if possible due to the unit will be used outside (not actually in the elements but subjected to outside temps/humidity etc...).

PJ Allen
01-13-2006, 03:46 AM
Well, since you've Posted in the BASIC Stamp Forum, then here's a link to how tobest implement it all with a Stamp --


01-13-2006, 04:11 AM
That's exactly what I am looking for I think. Sadly though its back ordered. Any other idea's?

PJ Allen
01-13-2006, 04:25 AM
I think that "VDD" should be VIN or a a voltage separate from the STAMP regulator's.http://forums.parallax.com/attachment.php?attachmentid=39494

01-13-2006, 04:53 AM

Bruce Bates
01-13-2006, 06:19 AM
Brian -

If your amperage requirements are 800 mA (.8 amps) or less, take a look at the attached data sheet for a great little semiconductor device which will switch A.C. line voltages using only a logic input (aka Stamp pin!). One MAY be able to parallel more than one of them to increase the total amperage which can be switched, I honestly don't remember. These take up about 10% of the space of an SSR or electro-mechanical relay, and probably cost a good deal less as well. I haven't priced any recently. There is also no requirement for a back EMF diode which would probably be required for an electro-mechanical relay.


Bruce Bates

Jon Williams
01-13-2006, 09:40 AM
If you want to control the SSRs used in the RC-4 directly, you can -- they only take a few milliamps to turn on at 5v. The idea behind the RC-4 is to free up pins and to allow a bunch of devices to be controlled serially.

Jon Williams
Applications Engineer, Parallax

PJ Allen
01-13-2006, 10:48 PM
Looks like those 3-terminal guys in your PDF aren't isolated from the "Mains" , "logic ground" = AC-/N (?)

Bruce Bates
01-13-2006, 11:07 PM
P J -

I'd like to think the information and test data in the data sheet would speak for itself. There is also a comment in there about separation of the "digital controller from the man switch" which follows:

"The ACS™ switch embeds a high voltage clamping structure to absorb the inductive turn-off energy and a gate level shifter driver to separate the digital controller from the main switch. It is triggered with a negative gate current flowing out of the gate pin."

That implies separation, if not isolation, to me. Additionally, it meets IEC610000-4-5 testing procedures which are defined here: http://www.emc-partner.com/resource/soft/database/TRA/IEC-61000-4-5.htm . Any more than that, I suppose you'll have to contact the manufacturer.

I've never had any feed-through, EMI/EMF or other like problems when I've used them at ordinary line voltages and frequencies.


Bruce Bates

01-14-2006, 04:15 AM
Will the stamp board be outside? If not a mechanical relay should be fine. Just use the existing switch wire to the light through the relay.
Unless you are trying to put the receiver unit with the light fitting I can't see the point in needing a relay at the light or outside.
I don't know how the wiring rules go in the US but only one line needs to be broken. What we call the neutral would go straight to the light and the relay makes or breaks the active conductor to the light.
Haven't played with Ir yet, is only one microcontroller needed or one at each end, transmitter and receiver?

This is how I picture it. If its' installed in an average sized home. But perhaps the installation is completely outside like in a park or a large backyard(acreage) then disregard my suggestion.

remote with transmitter - stamp board with ir receiver and relay at existing light switch - switchline to light.