Homey Community Forum

Using a plug to enable or disable a solar panel micro inverter

I have been wondering… Is it possible to use a power plug to enable or disable a solar microinverter that is connected directly into a 220V socket?

The reason i ask:

In the Netherlands you are only allowed to plug in solar panels of max 600W into an existing group with other consumers attached.

I now have 2 sets in the yard, both connected to the same socket in the shed. One set (2 panels) is max 650wp and the other one (1 panel) is max 330wp. Together they only give output above 600W if it is totally clear. The peak output is then, depending on the heat and the time of the day, around 750-780W.

To prevent any problems i was wondering if i can connect the single panel via a Coolcam plug (2500W) to switch it off if the output is too high.

It may depend on the inverter, some (most? all?) plug-in solar panels have smart inverters that won’t put out any voltage unless they are plugged in to a wall socket. Depending on how such an inverter detects its “plugged in” state, placing a smart plug between the wall socket and the inverter may cause the inverter to not output any power when the plug is turned off, which is exactly what you want.

A somewhat relevant thread on GoT: Smart plug die opbrengst kan meten - Duurzame Energie & Domotica - GoT

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Dependable on the other consumers in the shed, and their usage if it’s very very sunny, you could choose to switch thóse off (from power), only if solarpower exceeds 600W.

On the other hand, if only the (incidental) peak-output is at it’s very max. 180W above the allowed 600W. …
And the shed / outside power is on it’s own dedicated 16A breaker,
Then just don’t use devices which consume in total over 2800W on those moments.

It’s all about not exceeding 16A / 3680W whether the power is either consumed or produced, or both.

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Thanks, that was my thought too. The inverter indeed only works when plugged into a socket, thus also fed by 220V.
Only thing i am not completely sure of is if the plug’s electronics can handle the power in the other way. I tend to believe that if it doesn’t exceed 2500W it should be fine.

I know that the peak is not very high. But if something does go wrong, i am not insured if i didn’t apply to the the NEN regulations.
I believe my shed is on the same group as the living room and the kitchen (still have to find out for sure). And since the dish washer, microwave, water boiler and some refrigerators / freezers are on the same group, i don’t want to take too much risk…
Alas it is not possible to put the shed on a separate group, that would have been the best option (and would have made it possible to use more panels).

Ofc you should comply to insurance and NEN regulations.
If the shed is not on a separate group, I would recommend the “disconnect your solar inverter if power>600W” scenario you thought of.

I’m really curious what the insurance sais if the to be used smart plug does not comply to NEN regulations, or if it’s controlled by a radio signal (not 100% reliable) by a non-professional device (Homey).

To be really sure, and without questionable solutions/devices, you’d better connect the max.650wp set on a separate group I think.
Adding a breaker, and cable to f.i. an outside waterproof socket, is cheaper than an refused insurance claim imho.

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Yes, you are right, absolutely. At the moment i disconnect it manually, especially when we are not at home, so no problem. But if it is possible by a plug it is more easy to do so even when not at home and i forgot to unplug it.
I will try to test it tomorrow.

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Don’t put anything between the inverter and plugpoint. It’s not designed to work with 265v the inverter outputs nor unplugging it frequently. Just use both inverters on the same plugpoint without any extenders or anything inbetween the plugpoint. Anything below 1kW is fine as long as you don’t put heavy machines or anything else that can trip the circuitbraker. This is why the nen set these thresholds. Regulation regarding alternative power input loads on the network are going to change this or next year after the trial is settled.

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Clear statement. That is indeed something i didn’t realize. My Coolcam plug specs state a max of 230V. The Enphase IQ7 has a max nominal output of max 240V so this is really something to be taken in account.
Maybe i have to reconsider this option… :thinking: Or look for a plug that is also suited for use in the UK and therefore designed to be used with 240V…

Nominal 240v but it WILL output more in excess of 240v, usually around 265v.
NO ! Like i said do not use anything between the inverter and plugpoint period. Only thing that should be used is its original cord. Anything inbetween the plugpoint and the inverter voids waranty. Better even dont use a plug(point) at all and connect it directly with cable to the grid. So no plug and plugpoint inbetween. This version requires a solarswitch inbetween as you need to be able to turn it off. If anything use a separated solidstate relais 16A 230v controlled by fibaro or other relais driven zwave device.
Imho since you worried about the output of 780watts it is in my opinion the best way to just connect both and leave it be. If it on a dedicated 16A breaker it be fine. Without a dedicated 16A breaker , which is often the case , you should redirect the powerline of the shed to a dedicated breaker.

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