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Discussion Starter · #1 ·
Rather than get an inverter gen (or whatever) to produce cleaner power do some of you get something like a surge protector for electronics? I've heard of a line conditioner is that something that can work for the whole system? I guess there's a balance point where it becomes as expensive as buying a different generator?
 

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I doubt there's anything out there that can fix a distorted waveform, which is what typically causes high THD.

Line conditioners, at least in most of the products I've seen from TrippLite, APC, etc., involves voltage correction and surge suppression. But they don't/can't correct distorted sine waves.

It's always better to start with clean power, rather than make futile attempts to correct it downstream.
 

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Here's a great definition of "dirty power":

https:// www.tesengineering.com/electrical-engineering-what-is-dirty-power/

Out of all of that, requiring tons of research on all the individual elements of dirty power, I believe there are about two that we can grab hold of and do something about. One is power surges (lightning, grid, micro-surges in the home itself), and the other is THD (from a grid, from a genny, or from within your home).

Of these, in all my research, I've never found higher levels of THD to be a problem, so I don't do anything about it ... I buy lower-priced higher-THD gennies, like the Westinghouse wgen9500df, and I've run on such for more than 5 years, with never a problem. ymmv ...

OTOH, my research has led me to believe that power surges are a bigger problem, so I put in a load center SPD (protects from the grid-side), and smaller SPD's in front of any electrical devices I care about (protects from micro-surges inside the house). One day, I might even tackle lightning. Here's a thread on SPD's ...


Hope this helps ...
 

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Rather than get an inverter gen (or whatever) to produce cleaner power do some of you get something like a surge protector for electronics? I've heard of a line conditioner is that something that can work for the whole system? I guess there's a balance point where it becomes as expensive as buying a different generator?
Everything using sensitive electronics converts AC into DC as low voltage DC is what the circuits use. The use of analog power supplies in small devices ended decades ago in favor of switching power supplies. Those switchers typically have a wide tolerance for acceptable power and are immune to things like noise on the AC power. A voltage spike (surge) can do them in. Everything has a limit there. Surge protection is helpful and the largest source of damaging surges in not a backup generator but the utility. If you don't already, add whole house surge protection. Adding point of use protection is a good idea as well. My experience with running my house on the rotary generator is nothing electronic cares a wit. If I run the ceiling fans, they may make a faint hum. Cocks drift off time because the frequency they rely on is off. I have had issues with smart dimmers if the frequency gets above 60hz. They strobe. Had to be the dimmers and not the LED bulbs as the same bulbs on switches do not strobe. The biggest practical advantage of inverter generators are their solid output frequency and fuel economy. AC motors will be happier. I have read accounts of some High efficiency home heaters and refrigerators having issues. Mine operate correctly. Would I like an inverter? Yes I would. But I want to run the HVAC in the summer. The cost of powering that with inverters was too high. I could get by with an affordable inverter in the winter as my big energy draws then are natural gas.
On line conditioners, those large enough to power a home are very expensive to buy and costly to run. You are talking converting a 200 amp source into DC then running that through an inverter of that size to get back to clean AC.
 

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Rather than get an inverter gen (or whatever) to produce cleaner power do some of you get something like a surge protector for electronics? I've heard of a line conditioner is that something that can work for the whole system? I guess there's a balance point where it becomes as expensive as buying a different generator?
It depends on how much "output" your seaking. There are UPS units that you could power with a generator, and then use one of those units to power your equipment that requires clean power.
"An on-line, double-conversion UPS system works differently and is the type of UPS we recommend for use with a generator. An on-line UPS continually converts incoming AC power – whether from the main power supply or a generator – into filtered DC power, and then reconverts it back into AC power with a pure sine wave. That’s the clean feed of power your sensitive equipment craves. And as another benefit, an on-line UPS filters variations in frequency as part of its everyday operation, so battery life doesn’t shorten prematurely."
Just a thought.
Some businesses actually use a system such, and wire special outlets for computers, video cameras and recorders and such.
 

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Discussion Starter · #6 ·
If you don't already, add whole house surge protection.
How would you do whole house surge protection?

Adding point of use protection is a good idea as well. My experience with running my house on the rotary generator is nothing electronic cares a wit. If I run the ceiling fans, they may make a faint hum. Cocks drift off time because the frequency they rely on is off. I have had issues with smart dimmers if the frequency gets above 60hz. They strobe. Had to be the dimmers and not the LED bulbs as the same bulbs on switches do not strobe
My LED lights are not on dimmers and didn't really strobe, but sort of flickered in what appeared to be a fairly regular pattern. Maybe that's the same thing? So far I've only tried the generator once though so still have a long way to go to get familiar with how things behave.
 

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Context is everything.... are we talking about smaller gensets in the sub-8kW, or something bigger, commercial-grade?

Smaller power heads are more likely to produce higher-THD so if you intend to power mostly sensitive electronics with it, it would probably end up cheaper for you to just start with an inverter generator to power everything and then use conventional (pure sine-wave) UPS for loads that needs to run continuously through power switchovers.

To me, it doesn't make much sense to skimp on the generator and then make up for it by spending a lot of money on double-conversion UPS.

I have a conventional generator and I do understand the risks associated with it. I have taken an oscilloscope reading and it's not that bad. Granted, I don't have any means to measure the THD. Anyway, the economy is just against me if I go with an inverter and that's the main reason I went non-inverter.
 

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It depends on how much "output" your seaking. There are UPS units that you could power with a generator, and then use one of those units to power your equipment that requires clean power.
"An on-line, double-conversion UPS system works differently and is the type of UPS we recommend for use with a generator. An on-line UPS continually converts incoming AC power – whether from the main power supply or a generator – into filtered DC power, and then reconverts it back into AC power with a pure sine wave. That’s the clean feed of power your sensitive equipment craves. And as another benefit, an on-line UPS filters variations in frequency as part of its everyday operation, so battery life doesn’t shorten prematurely."
Just a thought.
Some businesses actually use a system such, and wire special outlets for computers, video cameras and recorders and such.
Do those devices have built in surge protection as a regular thing, or is it something you have to look for specifically?
 

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Line conditioners filter RFI/EMI in the higher megahertz range. They also have surge protection by using a MOV, or Metal Oxide Varistor. These devices dont conect current till they hit an avalanche voltage point like a surge. They short the line/neutral to trip the circuit breaker at your panel. The MOV sacrifice themselves before your equipment.

****Nothing at the portable generator level filters bad THD.

There are devices called line and load reactors (basically very large inductors) that act as high resistance shunts to the higher harmonics we don't want. That energy is converted to heat. The specs of these reactors is based on the load being powered so not easily done at the portable level.

Not all double conversion/ online UPS units can handle dirty power either. The battery charger powered by the incoming VAC likely has an Active PFC circuit which cannot tolerate high THD. Very seldomly does one find a Passive PFC circuit which doesn't care how much THD there is.
 

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How would you do whole house surge protection?


My LED lights are not on dimmers and didn't really strobe, but sort of flickered in what appeared to be a fairly regular pattern. Maybe that's the same thing? So far I've only tried the generator once though so still have a long way to go to get familiar with how things behave.
What I called strobe you might call flicker. They strobe/flicker at what seems to be less than 10 Hz. Maybe closer to 6 Hz. Definitely much slower than 60Hz which is not perceived by human eyes. It is something with the dimmer as the same bulbs and same brand as the dimmers only a simple open close smart switch and all mechanical switches operate perfectly. If I can keep the Hz at or below 60Hz is smooths out. Whole house surge suppressors are usually installed in the load center. The type I put in plug into unused breaker slots and have a pig tail wire which goes into a neutral or ground. In my load center the neutral and ground are bonded so what is the difference. There are other types which connect differently but they do the same thing. I put in several surge outlets which add more protection for house appliances. Frig, Laundry, Heater, dishwasher, microwave. Computers, TVs, routers, ect are behind UPS back up devices. Not using the power strip type suppressor devices.
 

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How would you do whole house surge protection?


My LED lights are not on dimmers and didn't really strobe, but sort of flickered in what appeared to be a fairly regular pattern. Maybe that's the same thing? So far I've only tried the generator once though so still have a long way to go to get familiar with how things behave.
best to check and see why things are doing the flickering.
it could be a sign of real issues like a bad ground for the whole house.
or a bad neutral.
first check all of the screws on the whole breaker panel and the meter socket connection.
a flir camera setup helps.
pm if you need links for those.

also meters are a good addition to any gen system.
they also help so you can see if you are spot on with your load balance.
 

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I buy lower-priced higher-THD gennies, like the Westinghouse wgen9500df, and I've run on such for more than 5 years, with never a problem.
Same here altho with different branding in the 6250 and 9000 range. The newest modern electronic in my place is a 2018 big screen, propane furnace is dated 2015, fridge is basic '15 or '16, well pump is old school using 120v. All work well with no issues or flickering lights as yet...Time will tell I suppose but it's been 6 years now for the 9000, 2 or 3 years of use here before I took possesion.
I also have/use on occasion two inexpensive 2200 low THD inverter gens that when paired up seem to make no noticeable difference in my appliances either, (that I can tell anyway).
A friend of mine a few miles away has a newer modern home/appliances and uses a 20 year old overseas 6500w gen and has no problem(s) that I'm aware of.

I get and completely understand that some of todays more modern (higher end?) appliances require the low THD inverter gens to operate, but it comes across to me like many of them do not.
In reality, how many gens & inverter gens get purchased/used with little to no concern of it's THD? Unless they notice the newer fridge or furnace not able to run on the gen source, it's not concerning to them.
As mentioned previously above, (at this time) I too am more concerned with power surging than THD.
 

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Some UPS setups convert all of the incoming power to DC and then invert it back to good quality AC.

Some act more like a pass through and just supplement the voltage during brown outs.

It might be possible to put a UPS at the appliances that are more sensitive, but that probably will cost at least $500 / end use load, maybe more.
 

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It might be possible to put a UPS at the appliances that are more sensitive, but that probably will cost at least $500 / end use load, maybe more.
It should be at this point that you consider putting your money on an inverter generator, instead of spending on several UPSs to correct something that shouldn't exist in the first place.
 

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UPS's, at least those at the home/smb level ($100 to $250?), put out good power (most designs), but they also cause THD on the house wiring. Perhaps the 1st consideration is "do I need to keep this thing running, and as a bonus, give it good power while protecting it 24x7"?

"Distortion can happen in any electrical system regardless of how the power is supplied to the system" ... and ... "grids at 99% of the time, and inverter-gen at 1% of the time" might be supplying good quality power, but they can't "clean up" distortion (THD) caused by everything else in your home. So, does the (expensive) device need protection from everything around it?

A UPS that is "always on" 24x7 might become necessary/wise for a $10k device (your hvac, $4k fridge, etc.), even if the UPS adds to that distortion level for other devices sharing the home's electrical wiring.

And another consideration might be, does the expensive thing have a good quality AND external/replaceable SMPS power block in front of it? These eat bad power all day long, and only present good power to the expensive device behind it. These may not need a UPS, unless your other requirement is "it must always be on".

Whereas, if the expensive device DOES NOT have an external SMPS power block, easily replaceable, then it might warrant the UPS, just because it's internal power board is weak in design (hvac?) or more costly to repair/replace. This thing may need a UPS, even if the owner's manual or the installer doesn't tell you it does.

I don't have or see the "correct" answer(s) ... just more mud for the water, but there's some trade-offs to be sorted through.
 

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It should be at this point that you consider putting your money on an inverter generator, instead of spending on several UPSs to correct something that shouldn't exist in the first place.
It seems for years, prior to some of our "newer" technology we ran with "generators" powering our homes for periods of time, and seldom did an individual encounter an issue.
Then technology improved? Or did it..suddenly we are worried about potential issues. OK, fair enough, but the question I have is just how "necessary" is an invertor generator for "back up power" when the intent is to "maintain" heat/light and cooling"?
Just as size of units is a variable, what does one truly need?
Cell phone charger..you can use your car, no UPS or invertor there.
Lights, again, lets be honest..how much do you need?
Freezer and fridge..are they impacted?
Heating and cooling..these units survive rolling blackouts and such
Now that big screen 58 inch tv..is it essential?
Computer? No power, most likely no WIFI or internet...
Until two years ago, I never owned an invertor generator, and from 2013 on I have had a generator for camping, both my travel trailer and camper. and yes, I boon dock...lots of "forestry" non serviced sites in my area..also use battery and solar.

So, the question, for those of us who just want the basics..light, heat and water..is an invertor necessary?
 

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UPS's, at least those at the home/smb level ($100 to $250?), put out good power (most designs), but they also cause THD on the house wiring. Perhaps the 1st consideration is "do I need to keep this thing running, and as a bonus, give it good power while protecting it 24x7"?

"Distortion can happen in any electrical system regardless of how the power is supplied to the system" ... and ... "grids at 99% of the time, and inverter-gen at 1% of the time" might be supplying good quality power, but they can't "clean up" distortion (THD) caused by everything else in your home. So, does the (expensive) device need protection from everything around it?

A UPS that is "always on" 24x7 might become necessary/wise for a $10k device (your hvac, $4k fridge, etc.), even if the UPS adds to that distortion level for other devices sharing the home's electrical wiring.

And another consideration might be, does the expensive thing have a good quality AND external/replaceable SMPS power block in front of it? These eat bad power all day long, and only present good power to the expensive device behind it. These may not need a UPS, unless your other requirement is "it must always be on".

Whereas, if the expensive device DOES NOT have an external SMPS power block, easily replaceable, then it might warrant the UPS, just because it's internal power board is weak in design (hvac?) or more costly to repair/replace. This thing may need a UPS, even if the owner's manual or the installer doesn't tell you it does.

I don't have or see the "correct" answer(s) ... just more mud for the water, but there's some trade-offs to be sorted through.
Agree that this topic is akin to a can of worms and it doesn't help when we overanalyze it. ;)

But just to put my point across, a UPS for a central HVAC would likely need its own room, wouldn't you say?

It seems for years, prior to some of our "newer" technology we ran with "generators" powering our homes for periods of time, and seldom did an individual encounter an issue.
Then technology improved? Or did it..suddenly we are worried about potential issues. OK, fair enough, but the question I have is just how "necessary" is an invertor generator for "back up power" when the intent is to "maintain" heat/light and cooling"?
Just as size of units is a variable, what does one truly need?
Cell phone charger..you can use your car, no UPS or invertor there.
Lights, again, lets be honest..how much do you need?
Freezer and fridge..are they impacted?
Heating and cooling..these units survive rolling blackouts and such
Now that big screen 58 inch tv..is it essential?
Computer? No power, most likely no WIFI or internet...
Until two years ago, I never owned an invertor generator, and from 2013 on I have had a generator for camping, both my travel trailer and camper. and yes, I boon dock...lots of "forestry" non serviced sites in my area..also use battery and solar.

So, the question, for those of us who just want the basics..light, heat and water..is an invertor necessary?
Technology did improve. More than anything, the improvement came in terms of added capabilities and efficiency. I've lived long enough to remember the 70's and 80's where wall warts used to be a small transformer with a rectifier, basic ripple filter, and mostly on exotic ones, a linear voltage regulator. These were bulky, heavy, makes a tad bit of heat and don't produce as much current for their size. They're inefficient as well, citing information from the web, they're only approx. 60% efficient.

Those have all been replaced with SMPS for their smaller footprint, lighter weight, larger current capability, and high efficiency (80-90%).

But improvements didn't stop there. SMPS in the last couple of decades, give or take, have been designed to also have power factor correction (PFC) built in. In a nutshell, this reduced the harmonics it emits back to the AC line by nature of its poor power factor from the switching circuit. The downside is, owing to these design changes especially with active PFCs, they also became more susceptible to or affected by harmonics from a high THD AC line. This is what makes them vulnerable... aside from voltage spikes, transients, etc.

As to your last question... well, it depends. Are you a betting man? :D

Go for an inverter generator if:
1. You can afford one in the size that you need
2. You run critical (ie. medical, emergency) devices that needs to work, whatsoever
3. You plan to use it for camping and to be as quiet as possible
4. You want something that is fuel-efficient

Go for a conventional generator if:
1. You're on a really tight budget
2. You need 12kW or higher
3. You have no issues with noise levels
4. Outages are relatively short and/or you're not worried about fuel consumption

My stand remains that it is unlikely that a conventional generator may cause actual damage. But it's not to say that it won't. In the end, it's really up to you how important your electronics are and if you're willing to take that chance.
 
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