Powerline voltage variation range in the house

[DineshR]

Hello,

 

This morning I happened to check the voltage in the house and noticed it was 261 v. Location - Korat, Thailand.

 

I finally decided to check because i've had a number of smart switches / sockets fail over the past few months and I attributed it to poor quality of the products - - switches / sockets. But maybe it's the line voltage ??

 

I thought the voltage should have been in the range of 220v +/- 10% i.e. max voltage at 242v. If 230, then max should be 253v.

 

Anyone have any insight into this ? Thoughts / ideas appreciated. Thanks.

[Crossy]

It's certainly rather higher than I'd like.

 

I'd log it several times a day and overnight, during the week too. Being a sad git, I (ok our data logger) log our voltage and current every 60 seconds 24/7/365.

 

If it stays constantly over 220V +10% I'd talk to your local PEA.

 

It's possible they are trying to compensate for an overloaded transformer during the day / week which results in excessive voltage at night / weekends.

 

Many of us would be grateful for some of your extra volts

 

[DineshR]

@CrossyThank you for your feedback. I don't have a data logger but a plugin that reads the voltage. It's been right around 260 pretty much all day today during the day. I haven't seen it at night though I will start to look at it at night as well. And as you suggest, I'll pay the local PEA office a visit. Now I'm worried about the stuff I have hanging off this voltage.

[Crossy]

Keep a written log with dates and times. You can throw this at PEA as evidence, but make sure you include weekdays too.

 

They may be able to simply swap you to a "better" phase, a simple and quick job, do try to work with them rather than against them.

[DineshR]

@CrossyThank you for your advice.

[bluejets]

Might pay to get a check on your "voltmeter" before you go jumping on the PEA

On 8/5/2023 at 8:01 PM, DineshR said:

plugin that reads the voltage

 

[Crossy]

51 minutes ago, bluejets said:

Might pay to get a check on your "voltmeter" before you go jumping on the PEA

 

 

I'd certainly invest in a cheap DMM (multimeter) just to double check.

[DineshR]

@Crossy A little embarrassed to report this but a reading with a multimeter showed 238 volts. False alarm. Looks like my plug-in is faulty. I had actually reported this to the PEA informally (I am facebook friends with one of the PEA guys from when we built the house) and he said it was exceptionally high and asked what I used to measure the voltage. Thanks for the help and apologies.

[Crossy]

No worries, these things happen.

 

It wouldn't be the first time someone has been misled by faulty test gear (this t-shirt I have).

 

But 238V is still rather high (220V +8%) so it's worth keeping an eye on it a low load times (middle of the night), just in case it gets excessive.

[norbra]

On 8/5/2023 at 5:03 PM, Crossy said:

Keep a written log with dates and times. You can throw this at PEA as evidence, but make sure you include weekdays too.

 

They may be able to simply swap you to a "better" phase, a simple and quick job, do try to work with them rather than against them.

Years ago I had a complicated phase swap.

Neighbors installed a largish AC and every cycle my lights would dim and TV picture shrink.

Supply guy came and switched me to the "white" phase which was lightly loaded at that time.

Some weeks later I complained that I still had problems,same guy came after a couple of hours he found that the "white" phase was incorrectly  marked at my pole so I got swapped to the real "white " phase all good

[BenStark]

46 minutes ago, Crossy said:

But 238V is still rather high (220V +8%) so it's worth keeping an eye on it a low load times (middle of the night), just in case it gets excessive.

Doesn't Thailand operate 230V network?

 

Using Goole I get conflicting results. Some say 220 other say 230.

[Crossy]

1 minute ago, BenStark said:

Doesn't Thailand operate 230V network?

 

Just to confuse: -

 

The MEA area (Bangkok) is 230V nominal.

The PEA area (everywhere else) is 220V nominal.

 

Both are supposed to be +-10%.

 

[KannikaP]

On 8/8/2023 at 6:28 AM, Crossy said:

 

I'd certainly invest in a cheap DMM (multimeter) just to double check.

They were called AVOs in my, and your , day.

[Crossy]

2 minutes ago, KannikaP said:

They were called AVOs in my, and your , day.

 

Many moons ago I was working in the RN calibration lab, at Monks Park in darkest Wiltshire, calibrating AVOs.

 

We had an AVO come in for cal. still in its "leather" case, slightly unusual but not unknown. Upon opening the case we found out why, inside was a kit of parts that had been, at one time, most of an AVO.

It turned out that Jolly Jack Tar was servicing a radar antenna and had "accidentally" dropped his AVO off the mast. Contact with the rather unforgiving steel deck converted said unit into a kit.

It was apparently less career-limiting to just send it for cal. than to report it damaged.

[KhunLA]

First house and electric service, living rural, and testing wall sockets, and what a range in voltage, 150-250v throughout the day.

 

That will wreak havoc on your electronics.  Had a couple UPCs for that reason.  That was 20 yrs ago, so hopefully, better now.

 

Another great plus with having solar.

[dingdongrb]

On 8/8/2023 at 5:36 AM, bluejets said:

Might pay to get a check on your "voltmeter" before you go jumping on the PEA

 

I was going to say the same thing. I've seen too many cheap instruments providing wrong data. That is why I have two Fluke DVMs.

[dingdongrb]

You should perhaps buy an expensive Tektronix o'scope and measure the ripple while at it.....  ????