# AC Mains Power conditioner question

saintsfan
Does anybody here have experience with whole house power conditioners? We live in an old neighborhood with old overhead powerlines, and it's been a rough fall for brownouts and other little transient "interruptions". I already have UPS's on delicate stuff (basement server, PC, home theater), but there are so many other little devices in the house that I'm getting real sick of needing to restart/reboot/reprogram. The furnace, water heater, microwave, etc all have clocks & timers & controllers that freak out when the power cuts for a split second. Worst of all is our hardwired smoke detectors; when the power flickers just right, they decide it's a conflagration and will wake everybody up at 3am just because there was a wind gust down the street.

I'd like to find something that can give first line surge protection and voltage regulation, but without a full UPS with batteries and significant runtime. Does such a device exist? How many liquor stores do I need to rob to afford one? Worst case I can isolate the circuit the smokeys are on and kludge in a cheap UPS, but if there's a better solution that will cover the whole place it'd be worth considering.

Staff Emeritus
What a bummer. That must be annoying. Unfortunately, a surge suppressor won't help. Only a UPS can prevent those devices from dropping out.

I've never heard of a whole house UPS, but perhaps others have.

Contact your neighbors. If they have the same problem, then their complaints to the PSC would add to yours. If they don't have the same problems, then you need to look at your own wiring, not the utility's.

There is one other thing you can do. Contact the public service commission (PSC) where you life and make a formal complaint about the power quality. In some places, they might be called a name other than "public service commission." Utilities are required to meed minimum standards, both on the average, and worst case. It sounds like your whole neighborhood should be renovated.

You might also call your utility and ask them for help on how to file a complaint with the PSC. That call might get more of their attention.

You should also keep a log book, documenting all such occurrences. Paper documentation speaks louder than verbal complaints. There are also power quality monitors that could document it for you, but the expense of that device should not be your responsibility.

Guineafowl
Guineafowl
I wouldn’t ‘put up and shut up’ with this, or try to solve it myself with expensive kit.

Our old rural house had flickering power just like yours. Called the power company, and they determined the transformer needed replacing. All done within a few days and problem solved.

Your supplier should check the transformer and wire taps, amongst other things.

Another time, I was concerned about the voltage sagging badly under load - lights dimming significantly when heavy loads were being run. The power company sent an engineer out to fit a ‘line recorder’, which sat there for two weeks monitoring the voltage. Turned out the sag was just within acceptable limits, but it was worth checking.

berkeman and CWatters
Gold Member
Dearly Missed
The power company sent an engineer out to fit a ‘line recorder’, which sat there for two weeks monitoring the voltage. Turned out the sag was just within acceptable limits, but it was worth checking.

I had a similar situation on a friend's house. His voltage was high, light bulbs didn't last and flickered visibly when airconditioner cycled on. refrigerator motor hummed too loud - all symptoms of high voltage. I read 254 volts on a cheap meter.
Power company service tech came out and measured, reported voltage was 252 and within his allowable limits but he'd report it to engineering anyway.
About a week later we saw a utility crew at work in the switchyard where his feeder originated.
His voltage dropped to 235, the fridge quieted down, and the 'flicker' on airconditioner start was tamed from "distressing" to "might not even notice".

moral of story - complain to your electric company. Might be as simple as a tree in need of trimming.

russ_watters
Dullard
I agree with the advice that you've been given (raise hell with your utility, and their overlords), but to address your original question:
There is a device called an 'automatic voltage regulator.' It boosts the load voltage during sags and reduces it during surges. It produces a clean sinusoidal waveform (not a cheap chopper). Complete outages of any significant duration are beyond the capabilities of these units, but they are perfect for places where transient loads cause out-of-limits voltage fluctuations. I pay about $3K for a 6KW 240/120 unit - they aren't cheap. Possibly useful: The utility in my area typically installs transformers (in neighborhoods) without much long-term thought. They will install just enough for existing demand, and ignore vacant lots which will ultimately connect to the transformer that they just installed. As an area gets populated, the transformers become overloaded - that's a common cause of the kind of domestic voltage variation that you're experiencing - your neighbor's air conditioner turns on and your clocks reset. It shouldn't happen with a properly sized transformer - you have to complain until they fix it - they do not volunteer to do it. If you notice that the problem is associated with loads in your house, you may have a bad connection at the transformer, or at your main panel. Science Advisor Gold Member Dearly Missed or at your main panel yes feel the panel for warm spots when heavy loads like water heater and airconditioner are running. Science Advisor Homework Helper Gold Member Is this something a Tesla Powerwall could do or are they grid tied and drop out when the grid does? Mentor yes feel the panel for warm spots when heavy loads like water heater and airconditioner are running. Or find someone with a thermal or csmera. Science Advisor Gold Member Dearly Missed these will smooth out distorted sine waves but won't replace missing ones. https://www.ebay.com/itm/SOLA-HEAVI-DUTY-MCR-63-23-210-8-CONDITIONER-POWER-LINE-TRANSFORMER/122846418068?hash=item1c9a379494:g:ixEAAOxydlFS88SS old jim dlgoff Science Advisor Homework Helper Gold Member Here in the UK if you complain enough they will come out and cut back trees from the line. I think it's the 11KV lines that have the problem. Mentor Does anybody here have experience with whole house power conditioners? We live in an old neighborhood with old overhead powerlines, and it's been a rough fall for brownouts and other little transient "interruptions" . With a name like @saintsfan, I suppose you're in Louisiana? That may be the least shocking location in the US to hear about such issues from. Still highly annoying. I do agree with others though that in the USA this should not be a "thing" and may in fact be illegal, so I would definitely complain to your power company. If you can get a small power monitor you can provide them evidence of the problem. I'd like to find something that can give first line surge protection and voltage regulation, but without a full UPS with batteries and significant runtime. Does such a device exist? How many liquor stores do I need to rob to afford one? What a bummer. That must be annoying. Unfortunately, a surge suppressor won't help. Only a UPS can prevent those devices from dropping out. I've never heard of a whole house UPS, but perhaps others have. This would be in the realm of a commercial grade UPS. You can buy them from Grainger, but you will need to have a load study done and hire an electrician to wire it. Perhaps even add a panel and have some things on it and others not. It isn't a small undertaking and it isn't cheap. Keeping an air conditioner running for 20 minutes would cost you on the order of$4000 just for the equipment.

https://www.grainger.com/category/ups-systems/ups-and-surge-suppression/power-meters-power-supplies-solar-transformers-and-ups/power-management-circuit-protection-and-distribution/electrical/ecatalog/N-qol

Dullard
Regarding UPS selection:
You have to be very careful about using an UPS as 'general purpose' back-up power. They're fine for feeding switching power supplies (as in computers), or resistive loads (lights, heaters), but many domestic rotating loads (motors) will self-destruct if fed with a low-cost UPS. If it produces a sinusoidal waveform, it's OK - These will be the more expensive units, and will often claim 'true sine wave,' (or words to that effect).

russ_watters
Homework Helper
Gold Member
+1

I have a mid range UPS that claims to be a modified sine wave but drives my alarm system nuts

Cosmodi
Using an electronic line conditioner to protect delicate electronic devices makes no more sense than using paper to protect paper. Yes, electronic line conditioners can be made with relatively rugged semiconductors, at least in comparison to those used in your vulnerable loads, but that’s just a difference in degree, not in kind…like using a “heavy duty” paper bag. From the other hand some line conditioners are based upon ferroresonant technology, and offer all the ruggedness, transient reduction and electrical isolation advantages of traditional ferro designs. See this one.

Staff Emeritus
In some parts of the world, the power grid and the power company are in bad condition, so customers have no choice other than to provide their own line conditioning.

In other parts of the world, the local power company can and should provide high quality service. In those places, it is the wrong solution for the customer to install their own line conditioning equipment. If it is the power company's problem, convince them to correct it. If the problem is due to your own wiring, then have it repaired.

We should keep that in mind here on PF where we have participants from all over the world.

berkeman
Guineafowl
+1

I have a mid range UPS that claims to be a modified sine wave but drives my alarm system nuts
Power inverters often describe themselves as ‘modified sine wave’, but have the following output:

So take ‘modified sine wave’ to mean ‘not a sine wave at all’.

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NTL2009, Fisherman199, Asymptotic and 3 others
Mentor
Regarding UPS selection:
You have to be very careful about using an UPS as 'general purpose' back-up power. They're fine for feeding switching power supplies (as in computers), or resistive loads (lights, heaters), but many domestic rotating loads (motors) will self-destruct if fed with a low-cost UPS. If it produces a sinusoidal waveform, it's OK - These will be the more expensive units, and will often claim 'true sine wave,' (or words to that effect).
Also, motors may have large inrush currents, so that could overload the UPS. This is definitely something that would need an engineer to study. I don't think the OP is going to go this way though...

Fisherman199
Does anybody here have experience with whole house power conditioners? We live in an old neighborhood with old overhead powerlines, and it's been a rough fall for brownouts and other little transient "interruptions". I already have UPS's on delicate stuff (basement server, PC, home theater), but there are so many other little devices in the house that I'm getting real sick of needing to restart/reboot/reprogram. The furnace, water heater, microwave, etc all have clocks & timers & controllers that freak out when the power cuts for a split second. Worst of all is our hardwired smoke detectors; when the power flickers just right, they decide it's a conflagration and will wake everybody up at 3am just because there was a wind gust down the street.

I'd like to find something that can give first line surge protection and voltage regulation, but without a full UPS with batteries and significant runtime. Does such a device exist? How many liquor stores do I need to rob to afford one? Worst case I can isolate the circuit the smokeys are on and kludge in a cheap UPS, but if there's a better solution that will cover the whole place it'd be worth considering.

I think you need to have a word with your provider. Problems like this should not exist if you're in a developed region. There are UPS/Generator subsystems where the UPS produces a sine-wave until the generator can have time to spin-up. These are expensive. Beyond that, there is very little you can do. I would get an electrician out to your house and have him look over all circuits. This is to make sure you're not inadvertently causing an issue somewhere. After that, go to the utility and have someone come out to place a power quality monitoring device on your service. My intuition says this is an issue from the utility side, but the Power-quality captures will have the final, correct say on that. A thermal scan of your transformer and service box would be useful as well. This is something the utility can do.

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russ_watters