Strange surges

Black_Widow

I recently started using an Owl electricity monitor and I'm getting read-outs as I would have expected them to be. All apart from these strange surges in kw/amp usage every couple of hours.

I first noticed them during the night time readings as they were most obvious seeing as the reading were pretty much on zero all night then I would get a reading that would be say 7 or 8 times higher for just a minute.

I wasn't too concerned about them at first but this morning there was one that was 15 times higher than the consumption in the minutes before and after. Now it's bugging me to say the least as the house is barely ticking over with only 2 wired smoke alarms, fridge, freezer and 3 alarm clocks drawing power.

Anyone else ever experience this or know what may be the cause?

meercat

possibly the compressor in your fridge and freezer kicking in for a couple of minutes
are you on a well or water main supply also
perhaps your immersion too

Black_Widow

Hi meercat

I'm on mains supply.
I highly doubt it's my fridge or freezer because I can see on the reports when they kick in and they don't coincide (I'm a bit OCD when it comes to monitoring stuff).

These surges only last about 10 seconds and I don't notice any changes in my electric supply when they happen.

Also immersion is never in use.

Also, the amount of kw being drawn in, even in the lowest surges, is at minimum 2 times higher than my entire house at peak usage.

meercat

nothing else springs to mind
10 second surges seems strange alright
you sure its not fridge or freezer(thats still my guess)

Bruthal

Domestic fridge freezers are low wattage, so the starting current would`t be very high, and the chance of the monitor which only reads for an instant every few seconds (usually 5 or so, or maybe 10 seconds in your case), and picking it up multiple times in a day at the instant the fridge starts, would be unlikely.

But if the monitor does pick up something starting, it will display that starting surge, or whatever it is, and display it until the next update, so whatever it is may not be lasting as long as the display is indicating.

Any outside pumps etc connected to the installation? Another thing the monitors would show would be an intermittent earth fault. But that would seem unlikely.

Timfy

Immersion heater?

Bruthal

Maybe someone is sneaking down and making tea and/or toast during the night:)

ted1

Plug out the fridge freezer for a while and see if it rules it out.

Is there a water pump.

Bruthal

What Black Widow needs to post up, is the actual readings. Saying it briefly went to 15 times what the reading was, would not mean too much if it was going from 100 watts to 1500 watts. But if its going from 500 watts to 7000 watts briefly, then that rules fridges completely out, but there might be some item being forgotten about in or around the house.

So exact readings, and durations required. If it is lasting exactly 10 seconds, then its likely something for a shorter time than that, but looks like 10 seconds because thats the update interval time of the monitor, and could be something starting up alright. This can be shown by switching on a kettle for example, and as soon as it registers, switch it off. It will still show untill the monitors next update.

I would be surprised if it was the fridge, very surprised actually. Their starting current is low, and lasts for milliseconds unless the motor in the compressor is sticking. And the milliseconds it lasts for would have to exactly co-incide with the very short monitor update/output time that happens each time it updates, which would be unlikely multiple times a day.

The running wattage of a fridge would be little more than 120 to 150 watts.

Black_Widow

Ok, I've unplugged absolutely everything in the house bar the fridge and freezer (it's a chest freezer by the way), 2 wired smoke alarms, laptop and modem. I think I can rule out laptop and modem as there have been spikes occuring while these have been completely powered down.
Here is an example of 2 spikes from yesterday when there was no-one in the house.
You can just about see the ups and downs from when the fridge and freezer kick in but then this huge spike and a smaller one a few minutes later.



If it's not enough detail let me know.
I do have a spreadsheet report with all the spikes highlighted if need be.

*EDIT*
Ok the more I look at the reports the more it seems meercat might be on to something. The surges really do seem to happen mostly, not always but mostly, as either my fridge or freezer motor kicks in.

Bruthal

Black_Widow wrote: »

Ok the more I look at the reports the more it seems meercat might be on to something. The surges really do seem to happen mostly, not always but mostly, as either my fridge or freezer motor kicks in.

It looks like something small anyway. I thought it was a high load suddenly appearing from your original post description. Judging by that, it could be the fridge actually running. A fridge would normally only be slightly more than a households base load. Maybe your monitor is detecting it starting, the one I have wont, because it does such a short output every 5 seconds, it just wont co-incide with the fridge starting except possibly on very rare occasions. 400 to 500 watts would be the expected starting load of a fridge freezer anyway.

If it is the fridge starting, it should show between 100 and 200 watts for a couple of minutes immediately after starting.

When a 100 watt incandescent or a halogen light is switched on as another example, it also has a starting surge of 5 to 10 times the 100 watt running load, and lasts longer than a motor starting current. And a halogen one could be a couple of hundred watts when running. No outside lights with sensors?

But if its only a spike of 400 watts etc, I would`t think much of it.

Black_Widow

Thanks for the reply but that is just one of the spikes experienced. We witnessed a "live" one a few nights back where the entire house was running, lights, playstations, tv's, the whole works. That combination usually never goes above using half a kw an hour but when the spike happened it jumped to over 2 kw an hour. It's not really showing in the reports because it only lasted 10 maybe 12 seconds. That can't be normal though can it?

Bruthal

Black_Widow wrote: »

Thanks for the reply but that is just one of the spikes experienced. We witnessed a "live" one a few nights back where the entire house was running, lights, playstations, tv's, the whole works. That combination usually never goes above using half a kw an hour but when the spike happened it jumped to over 2 kw an hour. It's not really showing in the reports because it only lasted 10 maybe 12 seconds. That can't be normal though can it?

Well like i was saying, they probably seem to last 10 seconds because the monitor likely updates every 10 seconds. So for example, if a 2kw load comes on for 2 seconds, in between monitor updates, it wont appear in the readings at all.

If however, this 2kw load for 2 seconds comes on a second or 2 before the monitor updates, and the monitor now takes one of its readings, the 2kw will suddenly appear on the monitor. The 2kw load goes off a second after the monitor takes its reading, but the monitor will continue to display this 2kw spike/load until its next update 10 seconds after the last one. This is just an example to try to explain how it appears to always last 10 seconds.

If it was the fridge starting current, then the monitor should show 100 to 150 watts for a few minutes immediately after it, until the fridge goes off again. But I still think its hard to see an energy monitor that only takes very intermittent readings catching the starting current of a fridge regularly.

Have you any outside sensor lights?

Black_Widow

Here's a look at the text report for the same surge as the image above. Highlighted in red and green it still just seems very high to me, keeping in mind that it shows a 15.5 times increase in consumption.

Black_Widow

Thanks Robbie, I can understand where you're coming from. I can see the duration isn't for a very long length of time but it is still concerning me regarding the actual amount of kw being used. To jump from .295 kw/h to over 4.588 kw/h, even if just for a few seconds, despite nothing obviously triggering it. I'm just worried about it being faulty wiring of some sort that could be dangerous.
My housing estate isn't known for it's top quality wiring. One house I know of still had full electricity supply throughout despite the main trip switch being off :eek: