Voltage measurement issue

Submitted by Starbuck on Thu, 03/03/2016 - 07:24

Hi,

My mains voltage has started to read 230v exactly, all the time. I used to work, wandering all over the place and up to 250v or more on occasion (quite normal here in rural Wales) then one Friday afternoon a few weeks back it decided to stick at 230v. Here is a screen grab of my power and volts at my house last night (the spike is the fridge).

Any suggestions? Thank you!

Jon.

Re: Voltage measurement issue

Submitted by calypso_rae on Thu, 03/03/2016 - 09:17.

What software and hardware are you using?

Re: Voltage measurement issue

Submitted by Robert Wall on Thu, 03/03/2016 - 09:36.

Is it this problem: https://openenergymonitor.org/emon/node/12188

Or has your a.c. adapter failed? - It will default to 230 V if no a.c. input is detected at startup (and if it restarts due to a mains dip).

Re: Voltage measurement issue

Submitted by Starbuck on Tue, 05/04/2016 - 13:11.

Emoncms version = low-write-v8.5

It is an emonPi with one current sensor CT, one voltage sensor transformer, and three temperature sensors.

I tried unplugging the voltage sensing transformer; the measured voltage stayed at 230v but the power went to 0w, so the emonpi can see it and it appears to be working.

Interesting that you mention it restarting when I get a blip on the mains (which is quite often) - my emonPi needs a manual restart as it hangs.

Re: Voltage measurement issue

Submitted by Starbuck on Tue, 05/04/2016 - 13:19.

Oh, hold on... I seem to have resolved it.

No idea how, but I have a value for voltage now.

Thank you both for your help!

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