Mains voltage monitor with logging?

[Werewolf]

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).

 

[Werewolf]

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).

 

[Werewolf]

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.

 

[Werewolf]

Strange, thought all inverters would have history of grid voltage along with every other piece of data.

I'm going to have another look but I can't see it on the main pages where the graphs etc are.

If the inverter doesn’t log it, how do they think they know

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).

 

[Werewolf]

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]

Small update. I received a raspberry pi today so setting up home automation to monitor it the smart plug voltages for a while (hoepfully i'll get that all running by the weekend).
Went overboard with a 16gb pi5 but i'll probably swap that down to the cheaper/cheapest pi5 in a while and repurpose the 16gb model for other things

 

[Werewolf]

Another small update.
Set up the home automation and was very pleasantly surprised to se the TP-Link P110 smart plugs with power monitoring showed up in it with voltage monitoring which means I have 4 voltage references from them around the house (or will do when I set up the last pair), and it hooks into the API for our inverter and logs the grid voltage from that (although that's only every 5 minutes).

So far in 24 hours the highest the voltage has recorded is 249, normally sitting at around 244 and sometimes dipping to about 235, so the mains voltage is a little high, but still fairly comfortably within the range allowed.