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Yes, maybe because the appliances need a more stable and strong source of power. there are appliances that are very sensitive and can get easily damaged by unstable power sources.
Do you have any personal knowledge of damaged electronic equipment due to the usage of a generator?
 

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Anecdotal evidence of old generators not having problems with old electronics (1980-1990's) doesn't have much relevance today. Taking just computers for example - the lithography used to make semiconductors and circuits are 1000x smaller than in the past. NAND used in RAM is hundreds of times more dense. Some things are more robust these days, but other things are much more delicate. Heck I could rub circuit boards from my old Apple II on the carpet and everything would be fine. I wouldn't dare do that with any modern PC peripherals.

Does this answer your question? No. But I still wouldn't run my expensive electronics without some form of protection. In my particular case I can't test it. 'Not because my generator is an inverter, but because all that stuff is protected by a battery backup anyway. Even through a generator, my computers get "filtered" by a pure sine-wave UPS.
 

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But are modern electronics really that more fragile? If any, to me most modern electronics seems more resilient. I am old enough to experience older electronics of that era having a higher chance of failure. For one, power supplies back then were the typical linear type. Many did have voltage regulator ICs but these also fail when the input voltage spike (being a linear design) gets high enough and overwhelms it.

Modern power supplies are more often than not, the switch-mode power supply (SMPS) type. And the great majority are of the wide input voltage kind that will work on any voltage between 100V to 240V. Also, by design, SMPS isolates the "sensitive electronics" from the AC line.

Here's a good video demonstration of an SMPS at work, filtering "dirty power" from an old generator.

 

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Anecdotal evidence of old generators not having problems with old electronics (1980-1990's) doesn't have much relevance today. Taking just computers for example - the lithography used to make semiconductors and circuits are 1000x smaller than in the past. NAND used in RAM is hundreds of times more dense. Some things are more robust these days, but other things are much more delicate. Heck I could rub circuit boards from my old Apple II on the carpet and everything would be fine. I wouldn't dare do that with any modern PC peripherals.

Does this answer your question? No. But I still wouldn't run my expensive electronics without some form of protection. In my particular case I can't test it. 'Not because my generator is an inverter, but because all that stuff is protected by a battery backup anyway. Even through a generator, my computers get "filtered" by a pure sine-wave UPS.
Thanks!
 

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From these discussions, electronic equipment does not seem to be affected by open frame generators. In the past, I've been advised not to operate refrigerators and other devices with compressors due to compressors and motors running warmer with open frame generators thus causing long term, down the road damage.

Sadly, I don't remember the specifics of these cautions but do recall the warnings. Any truth to this or explanations why this is just a bunch of phooey?

Jump
 

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There is some truth to that. But unless the sine wave is totally screwed up, inductive motors should survive on generator power with no long term effects.

With more appliances gradually moving into a brushless DC (BLDC) motor design, that is becoming less of an issue.
 

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An old thread with some recent activity, but I'll add my findings from our off-grid location:

1. been running only open-frame gennies (1st generac, now duromax 12000's), and these both fed the battery banks thru the inverter/charger, and the inverter passed-thru the excess power to the rest of the house/appliances. No problems to any devices, for over 5 years now of doing this.

2. any issue at all has only been, is there enough power coming through, before a device complains about anything. When we added a grundfos water booster pump, other things started complaining about the surge needed for that thing; a kickstart device is on order to smooth out that surge.

3. a german appliance (countertop dishwasher) is the only recent thing I've noticed that doesn't like to be on open-frame generator power. it appears to sense the state of power beyond it's plug, and makes decisions on that to run or not run, sometimes just for a few seconds (when grundfos kicks on), and other times to act entirely flaky (forget where it is in its cycle). We just don't run this device when the genny is feeding the battery bank. I've heard that german electronics can be this way, but can't point at any docs.

4. UPS's (consumer-class) ... they are a loss for operating when on our type of generators, as they click continuously, and run down the battery. In my case, the inverter/charger hogs the most power when on generator, and feeds some excess power thru to the rest of the house, but the UPS's just don't like what they get; less clicking when a 22kw generac fed things, more clicking on the duromax 12kw, but always some amount of clicking/battery run-down. As the whole house inverter/battery bank is basically a big ups, we did away with the little ones. I've heard bad things about what these ups's put back out on the line ... can't prove anything, yet.

5. because I'm off-grid, our genny operation seems to be mostly "straight-line", with genny running at a constant speed to feed the inverter/charger ... this is apparently a good thing, as the genny doesn't normally experiences all kinds of surges/demands from anything else. It mostly charges the battery bank back up, and then the fancy inverter switches automatically from charging the battery bank to feeding the house from the battery bank. genny runs about 3 - 4 hours every day, depending on solar panel activity; we consume about 200 or so amp-hours of power per day out of battery bank, and it takes our genny about 1 minute of run-time per amp-hour to put it back in.

So, we run all kinds of modern appliances, and being an IT guy, I run all kinds of computer gear. Never a problem with anything, other than oddities noted above on certain devices. After 5 years, can't really say anything has died an early/horrible death due to genny operations; they've all lived a normal life span. All electric house & appliances, some propane appliances where that makes sense in our cold southern colorado region, at 7500'.

THD of the open-frame genny has never seemed to be a problem, for us. My THD readings seem to indicate there is as much trouble coming from inside the house (the modern-day devices) as there might be from your genny; these devices (like the UPS's) can throw problems back out on the house wiring.

Having enough power at any one time seems to be more important, so gennies in the 10kw or larger arena is better. Running the genny to mostly charge a battery bank is better (even load).

Hope this helps ...
 

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How do you respond to that ^ ? lol

But I share your sentiments and as another person working in IT, neither have I encountered any issues with my "sensitive" computer equipment when running from a non-inverter generator. Granted that all of them are behind a mix of several APC SmartUPS and consumer-grade UPSs. Even so, none of them has ever reported any line quality issue in the logs.

And unless the UPS is the double-conversion type, it's not capable of fixing "dirty" waveforms. They work within a set of tolerances and when its internal logic decides that the power is acceptable, it just pass it along to the load. The only time a UPS intervenes is when it detects an electrical spike, voltage drop/gain (AVR kicks in), abnormal frequency deviation, or total loss of line power. Anything in between, the load (your sensitive electronics) will see the dirty waveform.... and it's fine. The SMPS will clean it all up.
 

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I should get me one of those tablet oscilloscopes. I've been dying to see just what sort of waveform my generator is churning out. Not to mention the UPSs and the few DC>AC inverters I have lying around.
 

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get a good one that has good numbers....
and name brand test gear holds value for good resale.
 

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I should get me one of those tablet oscilloscopes. I've been dying to see just what sort of waveform my generator is churning out. Not to mention the UPSs and the few DC>AC inverters I have lying around.
Can THD be calculated using one of those scopes?
 

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"because all that stuff is protected by a battery backup anyway. Even through a generator, my computers get "filtered" by a pure sine-wave UPS."

Correct me if I'm wrong, but in normal operation the UPS will just pass AC through to your electronics.

The only time you'll get a pure sine wave is when you're running ff battery power.

amirite?
 

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"because all that stuff is protected by a battery backup anyway. Even through a generator, my computers get "filtered" by a pure sine-wave UPS."

Correct me if I'm wrong, but in normal operation the UPS will just pass AC through to your electronics.

The only time you'll get a pure sine wave is when you're running ff battery power.

amirite?
The exception would be a double conversion UPS.
Exactly. Post 28.

A conventional UPS does allow filtering from certain line irregularities but smoothening up a jagged waveform and passing it on to the load is not one of them.
 

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"because all that stuff is protected by a battery backup anyway. Even through a generator, my computers get "filtered" by a pure sine-wave UPS."

Correct me if I'm wrong, but in normal operation the UPS will just pass AC through to your electronics.

The only time you'll get a pure sine wave is when you're running ff battery power.

amirite?
the units with constant avr will filter the ac.
you know if you have one...
lol
most run 500-600 bucks new and up on the price
 

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that is a little package!
yea you have to have an good ipad to get the good out of the unit for sure...
1K for a price point is ok.
is it update able?
or is it a one time deal...

these days anything with blue tooth is dated on how many years the blue tooth may work as far as version...

look at cell phones right now 1g,2g and now 3g will be off line later this month and maybe next month (late jan, end of feb 2022) so if you have an older cell phone it will be bricked on text and calls...
but the internet parts will still work if you have wifi...
and this affects some ipads with cell for the data connection.....

i hate to hijack the conversation with cell phone stuff..
but it does make a difference when buying any gear that is connected right now...
variants of 5g are already rolling out... and 6G is already in the works!
tech world is changing fast!
i still have tube testers!! LOL!! and the good ones at that!
GRIN!
 

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"because all that stuff is protected by a battery backup anyway. Even through a generator, my computers get "filtered" by a pure sine-wave UPS."

Correct me if I'm wrong, but in normal operation the UPS will just pass AC through to your electronics.

The only time you'll get a pure sine wave is when you're running ff battery power.

amirite?
You are correct. I am wrong. It was something I learned and then forgot! Thanks.
 

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Eaton Corp (power folks) has a wp (Harmonics in your electrical system) on the THD problem inside the house:

"Harmonics are a distortion of the normal electrical current waveform, generally transmitted by
nonlinear loads. Switch-mode power supplies (SMPS), variable speed motors and drives,
photocopiers, personal computers, laser printers, fax machines, battery chargers and UPSs
are examples of nonlinear loads. Single-phase non-linear loads are prevalent in modern
office buildings, while three-phase, non-linear loads are widespread in factories and industrial
plants.

A large portion of the non-linear electrical load on most electrical distribution systems comes
from SMPS equipment. For example, all computer systems use SMPS that convert utility AC
voltage to regulated low-voltage DC for internal electronics. These non-linear power supplies
draw current in high-amplitude short pulses that create significant distortion in the electrical
current and voltage wave shape—harmonic distortion, measured as total harmonic distortion
(THD). *The distortion travels back into the power source and can affect other equipment
connected to the same source.*

Most power systems can accommodate a certain level of harmonic currents but will
experience problems when harmonics become a significant component of the overall load. "

I'm not saying anybody shouldn't use an inverter/generator ... it's recently new to the home generator market. Perhaps reducing every source of THD is the answer ... on the outside (your generator), and then on the inside (your devices).

We don't use an inverter/generator (cost, complexity, etc.), but then, our off-grid inverter/charger (magnum) probably deals with the worst of THD thrown by our genny (duromax 12kw open-frame), and then all the rest of the time, we get clean sine wave power going into the house. Where, unfortunately, it then gets used by all the devices inside that turn around and throw THD back out on the house wiring ...
 
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