Mains voltage monitor with logging?

Werewolf

Werewolf

Werewolf

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Panting like a fiend
Just wondering if there is any suggestions for a (preferably) cheap plug in mains voltage monitor, that does logging, or at least records the highest and lowest values?

I've got a couple that show the current voltage, wattage, amps, hz etc but not one that can tell me the peak and low over time.

I'm asking as I had an interesting conversation yesterday with someone who was telling me our voltage was apparently spiking very high (high enough i'd expect dead appliances).
 
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If you use HomeAssistant then the Meross MSS310 smart plugs monitor voltage and it is logged/graphed in HA...
 
+1 for homeassistant and any smart plug, i use Athom V2 (ESPHome)

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What voltage ranges are you hearing about?

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I have various smart plugs (Gosund UP111) and https://docs.openenergymonitor.org/emonpi/technical.html that feed into Home Assistant. It's all then plotted on one graph, can see the voltage drop off the coffee machine when I put the oven on. This happens because they're on the same ring, far from the consumer unit.

What are your current plugs, maybe you can just log those to Home Assistant. Don't have to keep it running all the time, just long enough to log what you want.
 
cheers, my current smart plugs are tapo energy monitoring ones but i think they only do wattage.

The ones i've got that do voltage are older style dumb ones.

Basically i'm being hard sold a "voltage optimiser" with a suggestion that if i don't my solar system will not be covered by warranty and that they're seeing problems. I'm not seeing any problems logged with the system and my normal plugs are showing voltages normal (the highest reading i've seen was 247* on sunday at noon with the batteries full and 4k being produced by the panels), but obviously I'm not watching them all the time.
I've ordered some of the Meross energy monitoring plugs from amazon so I can set one up to log the voltage full time.

My suspicion is that they're talking out of their bum as every ~6 months it seems the compnay sends someone round to "check the system" who spends about 15 seconds looking at it, then about 20 minutes extolling the virtues of moving over to Octopus, or why we need a voltage optimiser.

As an aside, I suspect my local grid is monitored for voltage variance much better than many, we had test site for grid storage built nearby a couple of years ago, specifically because the local grid kept falling over due to demand (apparently the lead time on the new high voltage line was something like 5-10 years, the lead time on the grid battery was ~2 years).


*Well within the specs that UK equipment is meant to be able to cope with, as IIRC it's 230v +10%/-6% so between 216 and 253, obviously closer to 240 is better for us (my other plug in voltmeter was reading 243).
 
Voltage optimisers are a scam, a bodge to mask a balancing issue. All they do is shift the voltage range up or down. If they're saying that the voltage is too high, and they fit one to bring the voltage down.. you'll still have the same range only it'll end up too low. I don't know why the inverter output being 247v would mean that the system isn't covered by warranty. Seems odd.

4kWh isn't much export in the grand scheme of things 247v is fine (you can see mine peaks at more, and we don't have any local generation). There is a vide on YouTube by Artisan Electronics where there's a massive solar array causing voltage issues when exporting, but I'd recomend watching the reaction video by Actual Electrical Content if you want a deeper technical look into it (he covers voltage optimisers).
 
Yeah i'd want good proof that your voltage is too high before getting any kind of power conditioning installed.

If it is high it is totally worth it, we had issues in work where the voltage was about 260v and it killed the PoE on a few very expensive Cisco switches before we got some decent power conditioning boxes installed.
 
Cheers as I say I know he's talking out his bum, as I know just enough about mains to know the standards and what equipment sold in the UK is meant to operate up to (and that the local grid operator has a legal obligation to sort out the mains if it goes outside the legal range).
The Artisan electrics video is one I remember watching last year, part of why I know this is nonsense, i'm just sort of paranoid that if there is any problem they'll turn around and try to wriggle out of the warranty, which is a shame as when we ordered from them they were pretty good without too much hard sell and no real attempt to upsell at the time.

Looking at the reviews for the company it seems that in the last year or so they've had a spike in 1 star ratings due to dubious selling methods, it looks like they've possibly got a bunch of new salesmen.

Re the inverter voltage, i can't see it logging it on the app or website, but i can see it as a data point in the momentary information in a pop up (it's currently reading 244.5), it's a growatt 5kw inverter.
 
how long do these peaks and toughs last and how do you distinguish if they are attributable to reactive loads in your house - like a dehumidifier or tv could present ,
pretty sure my 3Kw pressure washer could well give a nice kick on the mains supply.
 
alphaomega16 said:
Strange, thought all inverters would have history of grid voltage along with every other piece of data.
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I'm going to have another look but I can't see it on the main pages where the graphs etc are.

GeX said:
If the inverter doesn’t log it, how do they think they know
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The guy kept mentioning they log more data, but he also said they've seen multiple faults lasting between seconds and hours that i've not noticed and are not mentioned in the devices fault log (there is one fault from last year that I cleared with a reboot of the system).

I think it's possibly a bit telling that i've not heard anything from them since I said I was going to have to have a look and possibly get some other quotes (lets put it this way what they were trying to sell me came to half the price of the original instal).
 
i've got the plugs so I'm looking at it now :)

it might give me an excuse to get a newer version of the pi ;) as i've got one that is first gen.
 
Werewolf said:
Cheers as I say I know he's talking out his bum, as I know just enough about mains to know the standards and what equipment sold in the UK is meant to operate up to (and that the local grid operator has a legal obligation to sort out the mains if it goes outside the legal range).
The Artisan electrics video is one I remember watching last year, part of why I know this is nonsense, i'm just sort of paranoid that if there is any problem they'll turn around and try to wriggle out of the warranty, which is a shame as when we ordered from them they were pretty good without too much hard sell and no real attempt to upsell at the time.

Looking at the reviews for the company it seems that in the last year or so they've had a spike in 1 star ratings due to dubious selling methods, it looks like they've possibly got a bunch of new salesmen.

Re the inverter voltage, i can't see it logging it on the app or website, but i can see it as a data point in the momentary information in a pop up (it's currently reading 244.5), it's a growatt 5kw inverter.
Click to expand...

I suspect your going to see more of this with solar cos.
They made hay whilst the COVID shortages and high energy prices were a thing.

Some seem to have reacted, accept that a solar installer isn't a £200 an hour job and are quoting semi-sensible money again.
Others (looking towards artisan here amongst others) believe they should charge this sort of amount.

Solar installers that got used to earning well into 5 figures a month are probably looking for work and "add ons" that keep those days rolling.
Selling voltage adjusting snake oil is going to be one of the target areas.
 
If you want an effective self contained system get a Shelly Energy Meter. Can be hardwired into the MCB and can operate on a wifi connection without hub. Accessible via Shelly App and can download raw csv data from the device for further processing. Its basically its own server with a web interface also.

I have a Shelly EM with 2 x 120Amp clamps, one of which monitors supply.

The Shelly smart plugs will also do the same thing if you want but obviously you need to plug it i ln to a socket whcih may not suit your needs.

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@Sin_Chase - are you able to calibrate that, because your voltage does actually look a bit high. The peak is out of spec, and the min isn't as low as I'd expect to see. The plugs I use are running Tasmota and then I've calibrated them agaisnt a Fluke multimeter - before that they were showing different readings to each other (and the EmonPi)
 
GeX said:
@Sin_Chase - are you able to calibrate that, because your voltage does actually look a bit high. The peak is out of spec, and the min isn't as low as I'd expect to see. The plugs I use are running Tasmota and then I've calibrated them agaisnt a Fluke multimeter - before that they were showing different readings to each other (and the EmonPi)
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Unsure about calibration to be honest. Thats only a 24 hour snapshot. Over the last 30 days the lowest seen is 221.5 and highest 259. I didnt install for voltage monitoring nor do I need ultra precise readings. I just wanted a general idea how much our hot tub was rinsing us on electricity :D
 
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