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Arduino to grid power

Arduino to grid power

Arduino to grid power

(OP)
I would like to use an Arduino to control the mains power feeding my house from an inverter. Ideally it would be a thing with a socket and a plug for mains power, and some sort of weatherproof 5V connection for the Arduino to control.

Now, this seems like a very obvious device to me, and I could easily build one (I did that sort of thing many years ago) but Shirley there must be such a device off the shelf? What is it called?

This sort of component will do the job, but I want a prepackaged solution with no exposed mains power terminals etc.

http://www.ebay.co.uk/itm/New-Temperature-Control-...





Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: Arduino to grid power

Mount the device in a suitable junction box.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Arduino to grid power

(OP)
I'm afraid in the People's Republic of Victoria the electrical trades union has a lock down on that sort of thing. Basically it would be an insurance nightmare if anything went wrong.

My best bet seems to be an off the shelf wireless or IR controlled plug, certainly doable,


All I really need is one of these off the shelf and certified

http://www.powerswitchtail.com/Pages/PowerSwitchTa...

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: Arduino to grid power

Explain a little more what you're trying to accomplish Greg: at first blush it sounds like what you really want is a "transfer switch", which is used to switch between mains and back-up power such as that from a generator- but you want to use it in the reverse direction, bringing mains in when you need it only. Is that the case? Google transfer switches- they're not cheap, but you can buy a decent sized one here in Canada at the local Home Despot.

The switching part of it isn't hard, although the solid state relay you showed would need to be mounted on a fair sized heatsink if you're going to switch inductive loads such as motors etc. on and off with it. But there's apparently more to it than just that- a proper sparky can give you the details.

RE: Arduino to grid power

I am not an electronics guy but part of me groans a little over using an arduino to control anything of importance.

RE: Arduino to grid power

I'm an ME so..... Set the arduino up with a servo to flip a physical switch on some existing, off the shelf hardware. Avoids all the regulatory or code issues too.

RE: Arduino to grid power


...and don't call me Shirley.

RE: Arduino to grid power

Did he mean Sheila?

RE: Arduino to grid power

I always wanted to build something like this - but was too afraid to do it:

STF

RE: Arduino to grid power

Furthermore,
Why aren't you considering a suitably-sized 4-pole relay?

STF

RE: Arduino to grid power

(OP)
Well now I've got a proper keyboard.

MM - transfer switch is the phrase I needed, and as it turns out that is what I have already when I switch from inverter to generator. An interesting question is whether I can switch from inverter to dead generator and back again with that push button, in which case I have a slightly frankenstein-like solution.

1gibson/sparweb - turns out motor operated transfer switches are a real thing. Nice bit of lateral thinking.

Another option is to use the control side of the inverter -it can already cut output if the battery SoC is deemed to be low, but unfortunately it doesn't allow for a proper boost/float/discharge sequence.

Another option is to cut the 48V DC power to the inverter rather than messing about with grid AC. This would rely on the inverter automatically restarting - I doubt it.

https://developer.mbed.org/components/PowerSwitch-... is what I am after, but it would have to be stamped and so on for use in Oz

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: Arduino to grid power

It's still a bit confusing with regard the the power level and the switch point you want a device for. e.g. switching the power mains (implying a generator transfer switch) versus the little PowerSSR Tail Kit for switching a cord and plug connected branch circuit load.

Your last post above infers UPS functionality. e.g. the ability to switch between inverter power and mains power, management of the battery state of charge, etc.

A separate question....in consideration of the nature of the load you want to switch, will be whether "Break before Make" switching by whatever you choose for your overall scheme will have guaranteed, sufficient delay time built in to avoid what could be damaging current surges due to out of phase switching between mains and the inverter output. If switching purely resistive loads, no problem, but if rotating motor or beefy transformer loads are involved, it could be a different story. Reclosers https://en.wikipedia.org/wiki/Recloser in the power distribution grid can "blink" the incoming commercial power in fairly rapid succession trying to clear a momentary short.. If your switch-over scheme is an automatic one, it needs to know what to do in this situation.

Provided the objective is a single branch circuit power level switching, it would appear that a cord and plug connected UPS listed for use in your country would provide the functionality you are looking for and would keep you on the good side of the "People's Republic of Victoria", insurance, etc). The automatic switching, phase synchronization for hand over of the load without interruption or damage when the AC mains are going nuts is part and parcel UPS functionality.

RE: Arduino to grid power

(OP)
I want to disconnect and later reconnect all power to the house. This is driven off one 10 amp socket on the inverter. That is, I can manually achieve what i want by switching the inverter off, or flicking the switch on the socket, or pulling the plug out.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

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