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"J.B. Wood" <arl_123234@hotmail.com>: Mar 20 12:38PM -0400 Hello again, everyone. I did some further online research and it appears modern inverters use fast-switching insulated-gate bipolar transistors (IGBTs) in sine-wave and modified sine-wave inverter designs. My guess is that a microprocessor controls IGBT firing times as well as engine speed (in an inverter generator) as AC output loads increase and therefore demand more DC at inverter input. The microprocesser itself would rely on a crystal as the reference time base (frequency) source which would ultimately determine the inverter's output frequency (e.g. 60 or 50 Hz +/- some acceptable deviation). So the crystal has to remain reasonably stable in a variety of operating environments. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com

"J.B. Wood" <arl_123234@hotmail.com>: Mar 20 06:57AM -0400 Hello, all. This isn't a repair question but, not having seen any circuit schematics, I've been wondering what circuitry constitutes the time base (what governs the 60 Hz AC output freq) in consumer inverter generators (e.g. the Honda EU series)? Is it crystal-controlled or something else? I'm assuming it depends on the inverter portion itself, not the rpm of the engine. Since these appliances are designed to function in a variety of temperature/humidity environments I would think frequency stability is important. Thanks for your time and comment. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com

Look165 <look165@numericable.fr>: Mar 20 12:14PM +0100 Might be a PLL locked by the mains. An independent frequency generator is too much expensive. Some of them have a tachometer to control rotation speed.   J.B. Wood a écrit le 20/03/2019 à 11:57 :

Fox's Mercantile <jdangus@att.net>: Mar 20 06:37AM -0500 On 3/20/19 6:14 AM, Look165 wrote: > Might be a PLL locked by the mains. > An independent frequency generator is too much expensive. > Some of them have a tachometer to control rotation speed.   That's not how it works. The generator supplies the raw energy to run an inverter. Locking an inverter to a crystal is simple, and you get and output frequency with 50 ppm accuracy.   Besides, what good does "phase locked to the mains" do when it's obvious that you're running a generator because the mains have gone down.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Fox's Mercantile <jdangus@att.net>: Mar 20 06:38AM -0500 On 3/20/19 6:14 AM, Look165 wrote: > Some of them have a tachometer to control rotation speed.   Typically, it's a governor, NOT a tachometer.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"J.B. Wood" <arl_123234@hotmail.com>: Mar 20 10:56AM -0400 On 3/20/19 6:57 AM, J.B. Wood wrote: > function in a variety of temperature/humidity environments I would think > frequency stability is important.  Thanks for your time and comment. > Sincerely,   Hello, all and I appreciate the responses thus far, but my assumption about the inner workings of these appliances is that the output voltage and frequency is independent of the rotational speed of the engine-driven generator portion. The generator's function is to supply DC input to the inverter which in turn provides the 120/240 VAC output. I'm assuming the same/similar circuitry as that of an inverter designed for connection to a motor vehicle battery. So what component(s) control the inverter generator's output frequency to the required degree of accuracy? Sincerely,   -- J. B. Wood e-mail: arl_123234@hotmail.com

Look165 <look165@numericable.fr>: Mar 20 04:04PM +0100 If mains are off, WTF wanting a 60Hz frequency ? Between 50 and 70 Hz, it's OK.   J.B. Wood a écrit le 20/03/2019 à 15:56 :

Pat <forums@greensdomain.com>: Mar 20 11:20AM -0400 On Wed, 20 Mar 2019 16:04:08 +0100, Look165 <look165@numericable.fr> wrote:   >> designed for connection to a motor vehicle battery.  So what >> component(s) control the inverter generator's output frequency to the >> required degree of accuracy? Sincerely,   What's it to you? For many applications, frequency isn't important, but for others, it can be. If frequency is determined by the the crystal clock of a microprocessor (my guess, but I really don't know), it should be easy to get pretty close to 60 Hz and clocks will keep good time and motors will run at the right speed. Some devices will run cooler at the right frequency, too.

Fox's Mercantile <jdangus@att.net>: Mar 20 10:31AM -0500 On 3/20/19 10:04 AM, Look165 wrote: > If mains are off, WTF wanting a 60Hz frequency ? > Between 50 and 70 Hz, it's OK.   You've obviously never had a ferroresonant transformer set fire to itself because it was dealing with a generator that was NOT on frequency.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Mar 20 09:03AM -0700 You need to see this as two entirely different systems, the output being dependent on the input for raw energy (watts), but not for frequency.   What comes off an automotive *alternator* is speed-to-voltage dependent AC, which goes through a diode-block and regulator and becomes chopped DC. Which, in turn is *smoothed* by the mother of all capacitors called a "Battery".   Which then goes into the Inverter - which does not really care whether it is alternator power, or battery power. It takes the DC at some voltage between ~11 VDC and ~15 VDC, and converts it to AC by its internal magic.   Peter Wieck Melrose Park, PA

"J.B. Wood" <arl_123234@hotmail.com>: Mar 20 12:11PM -0400 > Which then goes into the Inverter - which does not really care whether it is alternator power, or battery power. It takes the DC at some voltage between ~11 VDC and ~15 VDC, and converts it to AC by its internal magic.   > Peter Wieck > Melrose Park, PA   Hello, and that's a big detour off my original question, IMHO. Having said that I have no problem with what you stated. Sincerely,   -- J. B. Wood e-mail: arl_123234@hotmail.com

Tim R <timothy42b@aol.com>: Mar 20 05:24AM -0700 Cat zappers, on the other hand.......................

"pfjw@aol.com" <peterwieck33@gmail.com>: Mar 20 05:37AM -0700 On Wednesday, March 20, 2019 at 8:24:55 AM UTC-4, Tim R wrote: > Cat zappers, on the other hand.......................   True story:   We had a very large, fearless, but gentle Maine Coon named Boswell, who made it to age 16, and to 18 pounds before succumbing to cancer. In any case, he was a bit of a wandered, even when neutered. As we had an electronic fence for the dogs, we got a collar for him. The first day he wore it, he walked up to the edge of the property - we could see him twitch - carefully walked through the zap area, turned around and walked back. We went to the fence supplier and got the "super max" collar. Next day, he did the same thing.   Some cats....   Peter Wieck Melrose Park, PA

legg <legg@nospam.magma.ca>: Mar 20 08:17AM -0400 Bit of a sob story.   Looking for a quick electronic format service manual last Saturday - trying to complete a web purchase of that from samsungparts.com when their microsoft e-commerce gui goes bad ' cannot complete request' etc etc.   Send e-mail about this and get invoice for electronic format plus shipping ($x2). No service manual file in mail. I query further.   I need the manual that day. I get it after more searching, that day.   Response later - they only ship electronic format on usb stick or CD.   I tell them to keep their product and refund shipping costs that were never intended in the original purchase.   They ship four days (two business) days later, anyways.   Samsungparts.com - J&J International - stay clear of these jokers.   RL

Spare Change <noncompliant@notcompliant.zgq>: Mar 19 10:15PM -0700 On Mar 19, 2019, Winfield Hill wrote   > > I don't have the unit but am contemplating that > > it may somehow be useful on 12v, maybe derated.   > Why not buy one of the 12V models?   Because free is always better. Unless it isn't, as in this case.

John-Del <ohger1s@gmail.com>: Mar 19 09:49AM -0700 I often care less about the how than I am about the "who"..   For example, who put the ram in the rama lama ding dong?

Adrian Caspersz <email@here.invalid>: Mar 19 07:44PM On 19/03/2019 16:49, John-Del wrote: > I often care less about the how than I am about the "who"..   > For example, who put the ram in the rama lama ding dong?   And here lies the problem. Far too much reality shows on TV, and every other craft television show is made intentionally (well, at least here in the UK) devoid of technical content, so the audience can be shown yet another "who" instead of "how". Andy Warhol was right.   -- Adrian C

John-Del <ohger1s@gmail.com>: Mar 19 03:20PM -0700 On Tuesday, March 19, 2019 at 3:44:17 PM UTC-4, Adrian Caspersz wrote: > another "who" instead of "how". Andy Warhol was right.   > -- > Adrian C     I hope you're not suggesting that the UK has more mindless drivel "reality" shows than we do here in the Colonies. Them's fighting words.

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