Mains electricity: undervoltage and overvoltage

Some things don’t quite add up.

In theory, the only way I could see it working is if it was a voltage regulator that managed grid imports such that they were less than the overvoltage cutoff of the inverter. This may then allow continuous function of the inverter for local use without excess being exported. This would have to assume that this could be done and one was a high use of solar during daylight hours to consume the solar generated power which otherwise would not have had existed due to the overvoltage conditons.

I wouldn’t expect the distribution networks would allow export in overvoltage conditions (assuming the excess solar was transformed by the EdgeIQ to meet the grid conditions at the time of export. This would lead to further pressure on overvoltage conditions.

I see that EdgeIQ is on EM.

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The inverter itself is what controls whether or not export occurs, when the grid voltage is high, the inverter will limit export, or stop export altogether. Some older ones might shut down and need restarting. Areas with lots of PV systems can see high grid voltage due to lack of load on the local transformer through the middle of the day, which is probably set to a higher than standard voltage tap to cater for undersized cables.

The EdgeIQ device can’t really manage imports from the grid- that is determined by the appliances, lights etc that are turned on. If this device reduces the amount of power used, as claimed, then this will actually result in a higher grid voltage, as there will be less voltage drop between transformer and house due to the reduced load.

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Just read through the EM article about the EdgeIQ. Sounds like it is some sort of bi-directional regulator with surge protection, but as pointed out by Mark earlier, there are still incorrect claims about voltage and power usage in the article.

Also: " We literally separate the house from the grid, and there’s no other technology out there that does that."
That is not true either. Installing a battery and using an AC coupled battery inverter to run the house (mods to an existing system, or use a charge controller + battery inverter and no grid-tie inverter for DC coupling), and only having a battery charger to charge the battery from the grid in cloudy weather achieves the same thing, and protects everything from high voltages, as chargers can operate over a wide voltage range and don’t use more power at high voltages.

Battery inverters are extremely well regulated over a very wide range of outputs. Here, even under high loads I see 230-235V, and it never goes over 240V. I have a surge protector in my switchboard for lightning induced very high voltage spikes- IMHO everyone should have one installed.

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OK. So nobody liked my post of the ABC News article regarding the EdgeIQ device but fancy calling it a scam.

What next? Wil you guys even be suggesting this “world first free energy generator” is/was a scam.

http://www.ratbags.com/rsoles/comment/lutec.htm

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I do now Fred. :smiley:
I was also wondering what to do in my spare time for the past 5 days or why I kept that old reference manual on AC machines and power electronics. :cry:

It opened up the discusion point on several important items. I had prior to your post emailed the ABC after reading the news release, questioning the ABC over the accuracy and reliability of the content.

It had roused some vague recollections of electrical engineering science from last century before hitting me over the head with a claim of savings nearly equal to my annual electricity bill! Only 26 more days left for their response.

Is it a scam?
Selling tap water as natural spring water may be?
Selling natural spring water as having curative healing properties may be?
Presenting a poorly researched and written report is not a scam.

Relying on information from one individual with a vested interest in a new product to be reliable, presenting it without challenge or declaring there might be a conflict or bias is poor quality journalism. How the report presents puts arguably an undue emphasis on a view that favours the product not mentioned directly in the report. It also entices others to enquire. As some of us have done.

Collectively there is now a range of views from the Choice community on the Edge IQ as a product. Some of us more open eyed without perhaps any risk of technical bias.

Is the product a scam?
Only if it is marketed with claims that cannot be met once purchased and installed I’d suggest. Although some of the claimed results appear to be extraordinary. They are also presented with minimal supporting detail, product specification or qualification as to suitability of the product to meet an individual need. Nothing says it is just an idea or product still in development. You can commit to purchase as an early adopter?

Advertising only needs an asterix carefully placed, or words like ’upto’ or ‘could save you’ to open up the gap between ignorance and reality.

The science behind the product suggests that the product may provide a benefit to some residential users for a specific range of conditions.

Several of the Choice community members of team could easily swamp this topic with information that may or may not add benefit. There are Engineering Consultants that specialise in the areas of harmonic filtering, power factor correction, supply voltage optimisation and load balancing.

If the promoters of the Edge IQ were confident of the performance and benefits they could do worse than offer a couple of units up for trial and testing by Choice. For that we would be much better informed.

Anything that avoids us delving into how a rotating AC machine functions or that even as a motor it is also a generator. I’d also avoid power electronics and varying options for ‘buck booster’ design as well.

p.s. I’ll look at your free energy generator design once I sort out the instability’s in our Tardis.

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Thanks everyone for the detective work on this product. I’ll be sure to flag this product with our investigations team :+1:

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I know from bitter experience that Energy Matters is prone to hyperbole. They don’t seem to care about over-promising and under-delivering. So I don’t think they will be too concerned that the product they may be endorsing can’t do what is claimed.

image

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Apart from hooking up a meter explicitly, another way to get the voltage is if you have a UPS. Almost every UPS, including the old one I got for a few bucks on ebay, can report line voltage over a serial or USB cable. Anyone who wants to see the voltage at my place can check it out online at any time: https://io.adafruit.com/craigio/dashboards/mains-voltage

The fluctuations are well within range, but that is because I reported my out-of-range supply some years ago. (Peaking at over 260V at night.) That was when I discovered that a new transformer had been put in on my street. I was told that they are assumed to be correctly calibrated and aren’t tested unless someone complains!

So the one part of the ABC article that I’d take notice of is, yes, it is a good idea to test your mains voltage.

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@craig1
that’s another good option and a good pick up with the Electricty supplier. I suspect the story about the transformer calibration is just a poor excuse for a lack of management of your network, and checking the tap settings or line voltage when the transformer was installed.

I splurged and purchased from Jaycar a $20 plug in meter that also enables you to measure the power used by any appliance plugged into it.
https://www.jaycar.com.au/mains-power-meter/p/MS6115

I would not normally go this far to suggest a particular product however this is another easy way to do so and to get the benefit of knowing how much power you use for any appliance you can plug in. In my instance the kitchen fridge! Note I lied about the price, it’s actually $19.95 ea.

Note also as a mini review of the product from Jaycar that the screen display has a very small font and may not be easy to read if your power point is near the floor. I plugged an extension lead into the wall socket first to get the meter up to a readable level. There are more expensive versions around that have a readout on an extension or computer data output if you are that way inclined.

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I’ve had a couple of those units from Jaycar in the past, and both have died after less than a year. They were more expensive back then, I think I paid $29.95 at the time.
Also, the frequency meter was a bit dodgy, displaying 60Hz when the actual frequency from my inverter is 50Hz. The meter on my switchboard always shows within the range 49.97 to 50.02Hz. Voltage and wattage were pretty good, and the pf was pretty good too, being very close to what I’d calculated a few times.

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An article regarding claims that the grid frequency is now having a much wider variation thus stressing the generation assets.

Two questions.

Why is RenewEconomy promoting this issue, given it has as an organisation a focus on low impact environmental outcomes?

Isn’t the thrust of the suggested changes to the regulations that the large generators now have the wrong drivers in respect of grid stability. In response it is argued the rules need to be changed to restore the previous strategies that ensured grid stability?

The market is meant to fix this situation. It is meant to place a higher value on control of frequency and thus encourage more units to provide their services. Unfortunately, it is not working as well as it should due to basic flaws in its design.

Whether the current system and rules is causing equipment failures is speculative? The professionals behind the requested changes sit outside the generation industry. It’s not a criticism, only an observation on the possible limitations of the information they may have to rely on. They may be correct in their assumptions.

Our ageing traditional synchronous plant is failing more often than it used to – is this just due to equipment age? Or could it be because it is operating outside of its nominal design parameters

It will be useful to follow up whether the AEMC progresses the request further.

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I am a citipower customer and have recently had a PV system installed. According to my PV data logger the 5 minute average voltage at the feed in point for yesterday was;
Bin Frequency Cumulative %
220 0 0.00%
221 0 0.00%
222 0 0.00%
223 0 0.00%
224 0 0.00%
225 0 0.00%
226 0 0.00%
227 0 0.00%
228 0 0.00%
229 0 0.00%
230 0 0.00%
231 0 0.00%
232 0 0.00%
233 0 0.00%
234 0 0.00%
235 0 0.00%
236 0 0.00%
237 0 0.00%
238 0 0.00%
239 0 0.00%
240 1 0.35%
241 1 0.69%
242 3 1.74%
243 12 5.90%
244 7 8.33%
245 22 15.97%
246 30 26.39%
247 34 38.19%
248 23 46.18%
249 18 52.43%
250 24 60.76%
251 23 68.75%
252 26 77.78%
253 22 85.42%
254 26 94.44%
255 13 98.96%
256 3 100.00%
257 0 100.00%
258 0 100.00%
259 0 100.00%
260 0 100.00%
More 0 100.00%

So about 15% of the time was over voltage. For quite a few of the >253 V points the PV system was shut down automatically so not contributing to the voltage reading. Citipower is currently investigating.

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Welcome to the Choice Community Forums Graham :slight_smile:

That is an issue for many people, and I’m sure most of them do not realise their inverters are shutting down due to high grid voltages. Considering the standard is 230V, Citipower (or whichever company operates the grid there, whom you may not be a customer of) are operating well above where they should be.

See this thread where I eventually managed to get Ausgrid to fix the problem for my brother:

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