TV on/off sensor

Greetings to all you Cocooners!
I would like my Ocelot controller to sense when any of my TV's are on or off, are there some type of IR on/off sensor that can work with a LCD/PLASMA TV, I have a zantech 791-44 and a CB-12 to turn the TV on/off, and a wall mount receiver for remote control. Any help will be appreciated.
Digger said:
what if someone uses the on/off switch on the TV? How about a current sensing loop?
what do you mean if some one uses the on/off switch, how does the current sensing loop work?
if someone turns the switch on the tv itself on the IR wont know it.

So if you use a current sensing loop it will know when the tv is powered on or off either by remote or the switch on the tv.

The loop senses power on the line cord and can trip a zone or an input on a alarm panel or an automation module.

I am not familiar with the Ocelot so someone else needs to chime in to provide more details.
Keep in mind that all devices that allow a remote to turn them on and off, ARE ALWAYS POWERED ON, even when "OFF".

The power lets the IR sensor be active all the time. It is also what lets the TV remember what channels are active, which one you had on last, and how high the volume was set.

They are never really off and draw power all the time. All such devices are one of the higher users of power in your home. When OFF, they are still ON.
If there appears to be enough demand, I plan to offer a "power on" sensor. It would transmit a X10 ON or OFF command in response to power being switched above or below a programmable threshold. It would also include a status query capability.

The problem I see is cost. Just the Polycase and AC receptacle cost almost as much as a typical X10 module. Adding a low-volume printed circuit board and other components would make it a $50 widget.

Jeff, is this going to be a current sensor? If so, I would suggest adding some other trigger options. As you point out, the case and receptacle are the most expensive pieces so why not leverage that investment into a multi-pupose product? In addition to current sensing you could have line level audio trigger, (with instructions on how to pad for speaker level inputs) and maybe a dry contact output for some local control applications in addition to the X-10 out. In other words, a wider audience and range of applications for minimal additional cost.
Actually, the printed circuit board in low volume will be the most expensive item. The XTB board cost me almost $25 in small quantity. The board for this would probably cost about $10 at the quantity I would buy.

Yes, this would be a current sensor. I was thinking about adding the ability to monitor power consumption by perhaps sending a X10 command every time it accumulated a KWH. Or perhaps it could respond to a query with an extended command giving consumption since the last query.

Because of safety, I don't like the idea of having accessible terminals on a device that can be connected to the powerline. The required isolation circuitry and terminal strip would push the cost even higher.