Modify an am466 so on is off, off is on

[dhouston]

Dave Houston; The Appliance Modules output is controlled by a ratchet switch. The MCR100-B pulses one time to advance the ratchet. It does not stay on to hold a relay coil activated.
If it does not detect the On Off change. It will pulse one or two more times depending on CFL friendly or older and then give up.

Brian: How does it sense the state of the relay?

[JeffVolp]

Brian: How does it sense the state of the relay?

That is done through that "A" connection in the schematic you posted earlier.

Jeff

[dave w]

dave w, Is this the one on thisautomatedhouse.com?
http://www.thisautomatedhouse.com/Thermostat1.html

Yes sir, that is it. Thank you very much!!

[Brian H]

Yes it is the A connection for the older before CFL Friendly ones.

The new CFL Friendly ones are completely different electronics wise. Including a new controller IC. It also has a 330K resistor near the switched outlet but I have seen no schematics on the new ones.

[Noam]

Yes it is the A connection for the older before CFL Friendly ones.

The new CFL Friendly ones are completely different electronics wise. Including a new controller IC. It also has a 330K resistor near the switched outlet but I have seen no schematics on the new ones.

Yet they still have the same model number, of course.

[dhouston]

Yes it is the A connection for the older before CFL Friendly ones with a completely different electronics. Including a new controller IC. It also has a 330K resistor near the switched outlet but I have seen no schematics on the new ones.

In my modification, the outlet gets GND (but A does not) when the relay is in one state. In the opposite state, A gets GND (but the outlet does not). IOW, A lies about the state of the outlet.

The relay is still ratchet operated - it has just been made SPDT instead of SPST as designed.

Obviously, the point is moot for the OP but I thought it might be of interest to others.

It the relay cannot be modified, the same thing can be accomplished using a comparator to invert the state of point A at the input to the PIC (Pin 8 in the schematic).

[dhouston]

Yet they still have the same model number, of course.

Geez, you wouldn't want to confuse folks with multiple model numbers, would you? 

[trashisfree]

Dave, I don't need the article.

[Brian H]

You may have found your solution but others following the thread may find daves project interesting.

[dave w]

You may have found your solution but others following the thread may find daves project interesting.

I don't know how to post the article and I wonder about copyrights since Popular Home Automation's parent publication "Electronic House" is still in print. But I will email pdf to anyone who asks.

[Brian H]

Isn't it on the thishomeautomation.com web site already or is that one just a synopsis of the original?

[Knightrider]

http://thisautomatedhouse.com/Thermostat1.html

Silly me, I happen to know the webmaster fairly well. 

[Brian H]

KR; I thought you may know the webmaster. 

[dave w]

Isn't it on the thishomeautomation.com web site already or is that one just a synopsis of the original?

No it is the whole article. I think the pdf version may have larger diagram. Yeah I forgot what web site had posted the article. Thanks for your help. Now I feel dumb about it. Getting old, a lot of the brain juice has dried up I guess. Either that or I have been working around nerve agent too long.