Is it possible to turn off the TV via the Chromecast?

I have an older TV without any fancy smart stuff or integration. Using a chromecast it is covering my needs.
I've just installed a LED strip on the back of the TV as bias light, and I have had success with turning it on and off based on if the Chromecast is streaming anything using WATO (Thanks @bangali).
Now i want to expand it a little bit, hence the question, is it possible to use the chromecast to turn of the TV, when it haven't been streaming for some time?
I know the Chromecast can do it, as Google Home can do it via voice commands, but I haven't found any example of any other system being able to do it. Anyone that have done any research into this?
[RELEASE] WATO - When any Attribute Then this cmd Otherwise that cmd:

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The only way to turn off the older tv would be through either IR or cutting the power. The latter is a bad idea. You would be able to do that if you added harmony to your home theater, though. That will open more entertainment possibilities as well and you'll be able to trigger scenes when you turn your tv on or off. Harmony has an ir blaster to solve that issue.

Why ?

I think the TV have the capability as the ChromeCast is able to turn the TV on, so the TV has the HDMI CEC.

regards to cutting the power, there is two reasons:
Less is more. If I can do it with a unit I already have connected to the TV, then there is no reason to put in a socket for it also.
Secondly, I want it to be in standby so the Chromecast can turn on the TV when I start to stream. Maybe I could use a socket to turn the TV off and then on again, but seems excessive.

Cutting the power would be like unplugging it. There are boards in tvs that will fry up easily by doing so. An older ir tv would be broken in no time by essentially unplugging it to turn it off.

Is it your opinion or do you have experience on that ?
I don't understand why you'll fry your mobo by unplugging it. Unplug it means no power at all, thus no power to fry something. Residual current in condensers ?
It's not known that power outage (same result) will fry mobo's

Ok, set the power on after ? It's like power on your TV. But I'll agree with you if you spend your time doing this kind of operation (switch on / switch off) all the time. But a regular use has nothing common with that behavior.

There is even no HD in TV. So no moving parts (spin out), less risks. I'm an IT guy and I agree that power off a computer with a rotating HD can damage the process (and in fact, that's the writing of data on it, not the spin because of the autopark heads), but nothing comparable in a TV.

I checked the net for that. It seems there is no high risk with that. But I'm open for further explanations.

And it's not an argument fight here, I'm genuinely interested to know the technical info about the possible damages a total shut down might do on a TV (in fact my own TV - and a hooked fanless computer- is switched with a Zooz strip).

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I don't have any technical info for you. But I don't think it is a good idea... that said, I'm doing it.

I have a cheap small TV in the bathroom. A Chromecast is hooked to it constantly streaming the news. When I walk in the room, the motion turns on the power outlet and luckily (I assume not all TV's will) the tv automatically comes back to an on state. I'm not sure if the tv is returning to the previous state or if the Chromecast triggers it back on. When I leave the room, the tv outlet turns off cutting the power to the tv but not the Chromecast. I wouldn't do this with an expensive tv, and I am fully prepared for it to one day just not turn on. I've been doing this for over a year now, entering the bathroom several times a day.

The reason I believe it could be an issue, with no facts, is that maybe yanking and returning power could cause some form of surge. No idea though. I'm just willing to take the risk on that particular tv.

In my case, I just use my TV as a big screen to watch movies (my library is on my fanless computer) and I watch movies maybe once a week, or even less.

Cutting power to a device is not recommended because it is harmful for some devices. Whether or not your TV was designed thoughtfully with that in mind is an unknown so until you know it's safe to cut power to it you shouldn't do it. Most devices actually are are isolated in a way from their power source that you can cut power to them but it's not typically the power that supply that gets damaged.

Instead, the bigger issue with cutting power is damaging the device's storage. If data is being written back to any storage then it can be corrupted. In rare cases even read-only storage could be damaged. If the storage is damaged the next time the device powers on all bets are off. I would guess that TVs have had some type of storage for settings for quite some time. If the TV has a menu and settings rather than physical dials then it probably has storage.

But... cutting/adding/increasing/decreasing voltage (power) on devices that are not designed for it can cause higher than expected or lower than expected voltages across voltage dividers and circuits. If the resistance on the divider fails (sometimes the divider already being an important component but not often) it can cascade down through attached components until enough voltage has dropped by destroying components to stop. Also, some components won't last as long if the power is repeatedly cut from them because of heating/cooling or from being partially mechanical. Inrush voltage after power outages is sometimes higher as well which can be catastrophic to capacitors because it can evaporate or burn through the dielectric but that wouldn't be an issue here because the relay that would be cutting the power wouldn't introduce an inrush when operating (unless it was a really looooow quality relay).

You are safest to try a CEC HDMI approach. If you always use the Chromecast and never any other input you might be able to use the Google Assistant Relay to issue a voice command to the Chromecast to turn off the TV. That would only work if the TV was on the Chromecast input though.
Otherwise, I don't think there is a safe option unless your TV is network connected and implements some interface there.

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The TV is always on the Chromecast input as it is never used for anything else.
Problem is that I haven't been able to find anything that can activate the OFF CEC command besides Google home voice commands, and I don't have any google home products besides the Chromecast.

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