Three phase switch for 6KW 400V water heater

Hello, I have a simple question,
I would like to automate water heating with 6KW 400V three phase heater, Suggest me some hardware (switch) compatible with home assistant.
Thank you in advance

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Personally I’d use a contactor controlled by a relay with 240V rated contacts. Specifically because contactors are rated to interrupt that sort of current and quench any arcing quickly.

is the device already in operation?
Yes? For example, it is enough to Sonoff basic…

Isn’t? You need more than that! Circuit breaker 16A, contactor 20A, circuit breakers 2A for contactor control and Sonoff basic. And most likely still 25A - 30mA current protector.

new on the market? Smart contactor?

No just a dumb one controlled by esphome on an ESP board (look at the post category).

Well you wrote the question, I just answered it. I would not say your question was stupid though and you really should not put yourself down like that. Calling yourself an ESP expert seems a bit far-fetched though.

This is the second abusive post I’ve seen by you today. What is your problem?

I’m not aware of any rudeness

Controlling a contator with an ESP is a valid solution. We are in the ESPHome category, as I pointed out previously.

A person who gives such a question, threatens to be electrocuted and it is useless to talk to him about the topic of electric contactor.

Who said he’s wiring it up himself?

He may have an electrician cousin for all you know.

Even if he bought an off the shelf unit it would still require working with mains voltage.

Are you suggesting we should not allow mains related questions in the forum without a valid electrical contractor’s licence?

I will use contactron contolled by sonoff. Don’t worry - electrician will do wiring - not me
Thanks for help.

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There are laws and regulations in Europe that regulate this. In the event of a fire and it is proven that there was a “non-professional” intervention in the electrical installation, the insurance company will not have to recognize it as an insured event.
I recommend, at least a strong warning…

Definitely use a correctly sized contactor controlled by an ESP / Sonoff. It works perfectly. That is how I have automated my water bore pump. I used an ESP8266 (NodeMCU) connected to some relays which control valve solenoids and the pump contactor.

…and yes, get an electrician to wire it up.

(Note for the other authors: had my name on this site not been ‘sparky’ then me posting these things might make you think I’m doing dodgy electrical work without a licence which I am not. Moral of the story is don’t make assumptions about people without knowing the full story)

I just ask that question to be sure I will not pay so much.
The electrician said the contactron will do the job.
If the heater is 400V 6KW can you check this will be sufficient?
sorry for translate link:
EATON DILM 15-10 contactor (7.5 kW, 230V AC, 1NO coil)

At a quick look that should do the job based on the info we have about your load. It has a 230V coil so powering that from a Sonoff will work for you nicely

This contactor is absolutely NOT APPROPRIATE for these uses…

Why do you think that?

no need to think! just see!

What do you think you see?

There is nothing inappropriate in the specifications.

Really, please elucidate rather than making vague comments that help no one.

@czechlion/@anti-tom

Which is only true if you have contract with a insurance company (sometimes also called mafia).

If not and you are free - just go ahead and do your thing :rocket: