'Power Meter Plugs'?

Stigura

Sort of prompted by my own 'APC' thread ...

Amazon has about a thousand, identical, blue faced clones. £5.00 - 15. Pick ye price, really.

Is there one out there that's actually worth getting? I see ye can pay £40. But, only 'smart device' compatible ones seem to push the price up ~ or look any different.

I'm guessing they're about as much good as the similar thermometers and such? One step above licking ye finger. Are any of them at least worth a tenner? If only for the momentary novelty and amusement of plugging and unplugging every plug in the place?

kirk.

I wouldn't be bothering with plug-in energy monitors unless there was a specific concern

There too much gadgetry now in homes

10-10-20

Stigura, There used to be a difference between them, the branded ones were better, but from what I can see on Amazon now they are all around the same at the lower price-point. I have a cheap one here and it's pretty accurate what what it is. I'll disagree with @kirk. here and say that they are very handy devices to have!

Just pick one which is easy to use as I just hate having to get down on the ground to work out what the hell is on the display. This one here "seems fine":

kirk.

https://www.boards.ie/discussion/comment/121329052#Comment_121329052

I suppose ya I'd be monitoring the total usage and then individual outlets if there was a concern

How much of an issue is it overall . Isn't most of appliance usage calculated and then you get your bill and it's mostly accurate

Stigura

Okay. Just grabbed a matched pair of that exact one, 10. Twelve quid? Worth it for the amusement of playing with them 😁

Kirk; It's not really a serious issue, mate. Electric think of a phone number. Double it. Charge me. Trying to double check the **** they show me isn't going to change a thing there.

It's just, I asked about my UPS, and somewhere along that line, someone pointed out that Those things suck power like a train, all the time they're sat on ye wall and plugged in!

Thought I'd check That out, before splashing out on a new one. Might be costing me more to run than a new pc'll cost! 😲

Ezeoul

I have a couple of Tapo P110 smart plugs that monitor energy usage. They also calculate cost (you set the price per kw).

Pretty handy. If you're buying make sure its the P110 which is 13 amps.

They're harder to get on Amazon, (usually they have the P100) but DID Electrical has the P110 for €9.99

Stigura

@Ezeoul Thanks! Just rushed to check. Thankfully, these are 13 amp! 🙂

10-10-20

Small home UPS's aren't that bad. There are three different types: online (double conversion), line-interactive and offline.

An offline UPS is the basic type and that means that it remains passive until the power either drops, then it takes between 10 and 15ms to kick in and run off the battery. That means that it's base-load is very low, there isn't much going on with the UPS until it's needed.

Line-interactive is different, it's constantly watching the incoming voltage and modifies it if the quality drops. That takes a bit of work to do that, so it's less efficient than an offline type.

Double-conversion though is a different beast, they are somewhat inefficient at low loads as they constantly convert the incoming AC into DC and then back into AC again, and there is a cost for that as you have efficiency losses in both of those operations.

Lookup yours and see, but many of the home UPS's are efficient enough.

Stigura

Yeah. mine's an APC. One I have my eye on is an APC BE850G2. I figure they're a pretty 'safe' household name sort of brand.

If I didn't go digging about on the internet, hearing from people at the cutting edge of these things? I'd just go on Amazon and buy APC. Like last time 😐️

10-10-20

That model is....

so the consumption should be very low.

10-10-20

Here's a better model for your needs...

https://www.huntoffice.ie/apc-back-ups-pro-br650mi-ups-ac-230-v-390-watt-650-va-usb-output-connectors-6-black-br650mi-5409966.html

it's line-interactive too, so a better product than that other unit. Just be aware that the connections on the rear are C13/c14 sockets and not three-pin sockets.

Stigura

" Just be aware that the connections on the rear are C13/c14 sockets and not three-pin sockets. "

What?! ❓️

It's handy, 10-10-20. I just came back here to ask for more input on these plug things. Because I'm a good lad, I always try searching the last couple of pages, for anything close to what I want to ask? Found this! 😉 So; It not only saves me littering the board. It also alerted me to the one that nearly got away.

Now, You'll be the one to sort this anyway, I'd think, please? Got my meters. Had them both on freezers. Damn soon ran up against a brick wall. Was more active elsewhere for a bit. Asked there. Place cancelled me 🙄

Before it all went silent though, I'd managed to explain I was / am on a tariff that ~ for our purposes ~ amounts to 'Day & Night' rates. 'How do I set the cost rate?' Someone told me to add the two rates together. Get the total. Halve that. That ~ again, for our purposes ~ would be the ball park.

Fine. I did that. " 0.31665 ". (Lemon Song!) What ever. I fed the meter that. Jotted down the figures the meter gave me back. Told this other place. Crickets.

Okay. Damn myself! It's past my bed time and I'm trying to rush this, whilst trying to keep a semblance of sense. Try this, please:

Freezers appear (Middle line) to be sucking about " 478 - 481 " It fluctuates before ye eyes. There's a 'W' beneath it. I'm guessing that's the juice? What ever. (Lemon juice?)

Below that / bottom line, it said, after running for the first 24 hours: " 40.00 ". According to the scant instructions, that line represents Cost.

Trouble is, I've no idea what that means. Forty What, please? Cents? Would it make rough sense, to you, that an under counter sized chest freezer might cost about 40c a day, to run?

Thanks 🙂

10-10-20

Hi ya Stigura!

C13/C14 are these cables:

About the running cost of a freezer... 478w to 481w continuously sounds very high even for an old freezer. That's effectively 11kW per day. I don't think it's pulling that anyway.

Usually freezers have a duty-cycle where the consumption goes up and down, so it's normally around 20% of the time where there is high consumption and then the rest of the time is idle; you should be seeing that on the meter? If you work out the duty cycle over an hour, then you'd do this:

20% duty-cycle at 480w, 80% at 10w, for example:

( 480w * 0.20) + ( 10w * 0.80 ) = 104Wh (watt-hour) (energy consumption for 1hr)

So then to calculate the unit rate, you got some misinformation there... 😀 We don't have a 50/50 split on the day/night tariff, it's 23:00 to 08:00, so 9hrs of the night-rate. That's 37.5% on night-rate and 62.5% on day-rate. So that works out like this example:

20c night-rate for 9hrs, 40c day rate for 15hrs, for example:

( 20c * .375 ) + ( 40c * .625 ) = 32.5c average.

So yeah, not too far off your figure, so we're good.

So then to convert energy used over a day into cost, you would look at the kWh value and multiply it by the average unit cost...

So using our example again, we have 104Wh (per hour) for the freezer and a 32.5c unit price per kWh. Multiply the hourly energy by 24hours to get a day's Wh value, then divide it by 1000 to convert it into kWh.

104Wh * 24 = 2496Wh

2496Wh / 1000 = 2.496kWh (energy for the day)

Then 2.496 * 32.5c = 81.12c per day.

So your 40.00 above might be 40c alright, I was just using made-up values for the energy consumed by the freezer. 40c would be about right as that would be 1.2kWh of energy... that's around what a new freezer would pull per day alright.

Stigura

" That's around what a new freezer would pull per day alright. "

That's great news then! Because, no matter what the formula, or how hare brained my application of it? One thing's indisputable; And that's that both the 'couple of years old' freezer in my kitchen, and the Twenty year old one in my back room ~ practically identical, at a cursory glance ~ are pulling pretty much the same amount! Let's hear it for small, chest freezers! 😁

Certainly get ye point about crawling about, trying to get ye face close enough to one of these plugs! I'm lucky in that my main plug sockets are all at waist level. Dunno why. Dunno why people usually have them near the floor ~ then have to crawl about, getting at them. Only got two sockets at shin height. Pain in the arse (Knees) they are. Thankfully, things like freezers don't need a lot of plugging / unplugging, or course. And I have a small torch surgically attached to my hip too. Helps a lot 😎

Be an idea to knock up little 'extension leads', wouldn't it? Something we could plug in. Then, have the socket at this end at our height. Plug the meter into That. Just leave it on the side. Pick it up and examine it when ever.

That said? Just got my dinner. Stopped and stared at my freezers plug. Says " 80...." something, now. No idea what that means. Eighty quid? Make sense, actually. Two things, costing me 80+ to run? Sort of makes sense, I s'pose. Don't run a lot else here. Kettle. Computer. Microwaves.

Have to try putting one of these things on the computer next. Scare myself to death.

blackbox

If James Joyce wrote about power meter plugs!

10-10-20

https://www.boards.ie/discussion/comment/121494849#Comment_121494849

😆

@Stigura - have a happy Christmas - (if you celebrate it), and keep safe and well!