Advise on generator operation

[(Chip)]

I have a Honda eu3000is generator. Should I leave it in eco mode? I have not tried it yet to see if it will run my 15k btu AC. Should I test it, or is it a bad idea for the generator or AC sake?

 

[Kirk]

Eco mode is fine for must of the time but not if using the air conditioner or the microwave.

 

[Mark_K5LXP]

When the generator is running in eco mode and there is a sudden high demand load there will be a slight delay before the generator can respond by throttling up. Some loads may not care, others may not like the delay and reset or have "undesired" operation. So if it's anticipated you'll be applying loads say, greater than 50% of the generator capacity just leave the eco mode off. The way I work it is to run it with eco off at first, then once the loads are on I'll try switching eco on and see if there's any reduction in throttle. If not I leave eco off.

Mark B.
Albuquerque, NM

 

[JayArr]

Hi Chip

Do you have a sound meter app for your phone? I use a free one called "Sound Meter".

I've been wanting a decibel reading for a Honda eu3000, under load (not in eco mode). I'm building a comparison chart.

The specifications at the Honda website say it's 57 dBA at rated load but they don't specify at what distance from the generator that measurement was taken. One standard is 21 feet (used by the federal parks service in campgrounds) but another standard is 50 feet.

If you could you take a reading with it in operation at 21 feet with your air conditioner on and then walk to 50 feet and take another reading I would be very thankful. I suspect the 57dBA reading is at 50 feet and at 21 feet you'll read 68-72 dBA

Thanks
JayArr

 

[phil-t]

I don't know about those sound meter apps. They might be OK for a relative reading, but don't think they are too accurate. Might depend on the phone? I have that app, and a couple others, that I have tried. Trying to get a reading on the sound level of my ATV exhaust. Some of the trails I ride have a max sound level requirement. I ran into LE on the trail the other day and they had a sound meter device. Different readings than I was getting at home. My app reading was quite low in comparison, i.e. 86 and mine was at 79.

 

[FunSteak]

Hi Chip

Do you have a sound meter app for your phone? I use a free one called "Sound Meter".

I've been wanting a decibel reading for a Honda eu3000, under load (not in eco mode). I'm building a comparison chart.

The specifications at the Honda website say it's 57 dBA at rated load but they don't specify at what distance from the generator that measurement was taken. One standard is 21 feet (used by the federal parks service in campgrounds) but another standard is 50 feet.

If you could you take a reading with it in operation at 21 feet with your air conditioner on and then walk to 50 feet and take another reading I would be very thankful. I suspect the 57dBA reading is at 50 feet and at 21 feet you'll read 68-72 dBA

Thanks
JayArr

Standard testing distance is usually one meter. Be careful with the apps as they aren't calibrated. Reasonable for relative measurements, though.

 

[JayArr]

That's interesting, maybe I should buy a real sound meter instead of trusting a free app.

The trouble with the Honda specs is they simply omitted the distance at which they got the 57dBA reading so there is no way to duplicate it or verify it. Obviously done on purpose so they can claim to be quieter than Yamaha or Champion without any way of proving them wrong. It always makes me suspicious when a company deliberately fudges the numbers.

 

[FunSteak]

That's interesting, maybe I should buy a real sound meter instead of trusting a free app.

The trouble with the Honda specs is they simply omitted the distance at which they got the 57dBA reading so there is no way to duplicate it or verify it. Obviously done on purpose so they can claim to be quieter than Yamaha or Champion without any way of proving them wrong. It always makes me suspicious when a company deliberately fudges the numbers.

They most likely tested at 1m, since that's the norm.

Here is a meter with +/- 2db for only $60. Probably not a calibrated, verified unit, but certainly a whole lot more accurate and reliable than a phone app.

Will you post your results here eventually? This is an interesting experiment.

 

[JayArr]

Hi Funsteak

Yes, I'll post the results here as I get them. The first part of the comparisons was done by a youtuber

There is absolutely no way that the Honda spec was at 1 meter, watch the video, the Honda generator he is testing is around 90dB under load and that's at only 1500 watts (right beside it). The spec on the Honda web site lists the noise spec as 57dB at rated load. That's a HUGE disparity. He walks away from it and the readings go down but they don't get anywhere near the advertised 57dB until he's at 50 feet!

He doesn't test a Honda 3000 unit and that's the data I'm trying to collect.

It appears that Honda is fudging the numbers, they list impossibly low numbers with obscure terminology like "at rated load" and they deliberately fail to list at what distance.

 

[Gary RV_Wizard]

Standard testing distance is usually one meter.

Whose standard? It's certainly not a standard in the generator world.

 

[Gary RV_Wizard]

Mark gave a good summary for Eco mode. When the a/c compressor kicks on, the Honda is going to hesitate a second as it tries to catch up with the sudden, large increase in amp load. Neither the generator nor the a/c will like that much. But if the a/c is running steadily to continuously deliver chilled air, that never happens. Still, probably best to turn ECO off while the a/c is running. Eco is really intended to improve fuel efficiency for light loads

 

[Larry N.]

There is absolutely no way that the Honda spec was at 1 meter, watch the video, the Honda generator he is testing is around 90dB under load and that's at only 1500 watts (right beside it).

He wasn't near 1 meter in the first test, but 58-60 at 50 feet isn't too bad. The 1500 watts is about all I'd expect a 2000 to do on a continuous basis, so that's close to full load. I also have to wonder what else was contributing to the noise, since this wasn't an isolated area, and the garage may have been echoing some sound to increase the reading, even the house and surroundings may have echoed a bit.

Also, was the guy on the tube using A-weighted or C-weighted noise levels on his meter (my Radio Shack meter will do either one, and there's a difference).

As a quick check to compare different generators the Utube guy had a decent setup, but for accurate measurements (anechoic or hemechoic chamber?) you need to find out what the measurement techniques were for the manufacturer's specs.

Still, even your ears will tell you that a Honda 2000 under load isn't quiet, but also isn't nearly as noisy as many others (and may be roughly similar to Yamaha, Champion, et al).

You might find this link interesting: https://www.me.ua.edu/stal/Pages/PDF/HondaNoiseTests.pdf
This one as well: Testing the acoustical noise of a generator set and interpreting the data - EE Publishers
Here's another: Best Quiet Generator Reviews - Rated Quietest in 2021

Lot's of good info there.

 

[JayArr]

Thanks Larry, you've corrected me, I thought the Forest Ranger was looking for 62dB at 21 feet but it is indeed 50 feet. If the Honda specs are for 50 feet, as I suspect they are, the 57 dB is a great number.

In the youtube video at 50 feet under load the Honda 2000 is 60dB and the open frame gen is 72dB. That's more than twice as loud and too loud for the parks service. It should be noted that the open frame unit is 3500W, so 1.5X the size of the Honda and it matters since it runs at 3600RPM all the time and has an engine sized for full load 3500W. It's a bit of apples to oranges.

The unit I'm building is 8HP and 3600W, I'm trying to get it to park service level so let's hope the low tone muffler and the quiet box will bring it below 60dB at 50 feet. I need 22 amps at 120V to run my inverter/charger to charge the batteries at 100A.

 

[Larry N.]

more than twice as loud

16 times as loud -- +3 dB is twice as loud, in actual sound pressure. That said, the ear's response is such that that same 3 dB is only a little louder as perceived by the ear, so it probably does sound twice as loud, or a bit more.

While the Honda engine has a good muffler, a lot of the reason that their unit is so (relatively) quiet is the insulation they put around the inside of the case, and sealing in the noise. So you'll need to work at it to get the unit down to that spec. Hope that quiet box does the trick.

Good luck.

 

[JayArr]

The open frame generator in the video certainly didn't sound 16 times louder than the Honda.

The insulation that Honda, Yamaha etc puts on the inverter/generator is the same principle as a quiet box. They are just integrating it into the construction.

The exhaust is actually a small portion of the noise of a small engine, there are videos of guys putting car mufflers onto small engines and it doesn't make them much quieter. It helps but it's not a solution by itself.

 

[Lou Schneider]

The trouble with the Honda specs is they simply omitted the distance at which they got the 57dBA reading so there is no way to duplicate it or verify it. Obviously done on purpose so they can claim to be quieter than Yamaha or Champion without any way of proving them wrong. It always makes me suspicious when a company deliberately fudges the numbers.

Here you go, a chart listing the SPL for all Honda generators and how they measured them.

http://cdn.powerequipment.honda.com/pe/pdf/misc/Honda-Generators-dBA-Chart-2018.pdf

EU3000i
50 dbA (25% rated load) - 57 dbA (100% rated load

"Tested in accordance with ISO 9614-2, sound pressure level calculated at 23 ft. (7 meters) using the front plane of the generator (control panel side) per ASHRE handbook 2017."

You have to be careful when using video clips to compare sound levels. Most non-professional video cameras incorporate some kind of Automatic Gain Control to normalize the audio level, so two different generators with widely varying noise levels will sound about the same when the video is played back.

 

[Larry N.]

The open frame generator in the video certainly didn't sound 16 times louder than the Honda.

No, that's because the ear doesn't respond in a linear fashion. Subjectively it probably was much as you described above, something more than twice as loud. The 16 times is the actual sound pressure, but the ear notes it more like logarithmic.

 

[CharlesinGA]

I know what others are saying, in eco mode the generator is going to bog and hesitate before it gets wound up and producing more power, but for the A/C you could easily install a soft start kit that is designed to help the A/C start with a marginal generator, and this should get it/keep it going until the generator catches up.

EasyStart™ 364 Soft Starter

The Best Soft Start For RV AC Units - SoftStartRV's RV AC Soft Starter Kit

These kits are stupid expensive for what they are, but they do work.

Charles

 

[JayArr]

Interesting chart Lou but i just don't know if it's believable.

The chart says at full load and 21 feet the Honda will read 57dBA

The video shows that under a less than full load (1500W) at 20 feet the Honda reads about 68dBA.

So do I believe the promotional handout printed by the Honda marketing department or the video of a real live test?

Good point about the AGC in video recording though, I had forgotten all about that.

 

[kcmusa]

10db is twice as loud
3db is twice the audio power.