Inverter Generator

[Ralph Mowery]

In article <DaydndxaSbmMgAjBnZ2dnUU7-VOdnZ2d@giganews.com>,
jdangus@att.net says...

Digikey has for sale crystal oscillators that can be programmed for most
any frequency for around 2 to 3 dollars. I have even ordered them
already programmed for about $ 4 each. I am sure in quanties of
thousnads from the manufactor they are very inexpensive.

I have ordered those for a project.
Certainly cheaper than having crystals made for $18-20 each.

$ 10 to 20 is inexpensive for a special made crystal now. I only know
of 2 places right now, Bomar that last report was $ 50 per crystal and
minimum of $ 100 for an order. Another in England that is I think about
$ 30 per crystal.

 

[Dave Platt]

In article <MPG.36ff177e8da2d6379899ac@news.east.earthlink.net>,
Ralph Mowery <rmowery28146@earthlink.net> wrote:

Digikey has for sale crystal oscillators that can be programmed for most
any frequency for around 2 to 3 dollars. I have even ordered them
already programmed for about $ 4 each. I am sure in quanties of
thousnads from the manufactor they are very inexpensive.

I have ordered those for a project.
Certainly cheaper than having crystals made for $18-20 each.

$ 10 to 20 is inexpensive for a special made crystal now. I only know
of 2 places right now, Bomar that last report was $ 50 per crystal and
minimum of $ 100 for an order. Another in England that is I think about
$ 30 per crystal.

Those programmable-frequency oscillators may have distinctly worse
phase-noise characteristics than a real crystal in a good oscillator
circuit. They may not necessarily be suitable for communications
projects or others that are sensitive to phase noise / jitter.

 

[bitrex]

On 3/22/19 1:25 PM, Ralph Mowery wrote:

In article <efc72184-b65b-478f-85aa-c87e0b1b42a0@googlegroups.com>,
tabbypurr@gmail.com says...


The cost of small microprocessors and crystals are almost nothing. Look
at the Arduino processor boards. They can be bought from China for
about 2 ot 3 dollars. They are powerful enough to run the inverter part
of the inverter.

No sensible manufacturer is going to use a crystal` where they can use a ceramic resonator or a silicon oscillator built into the chip. And no sensible mfr is going to pay for a crystal plus a divide by massive number circuit when they can use a low frequency oscillator. If you can't see why there's nothing further for us to
discuss.



I guess that I used crystal too loose. Anyway the small processors and
clock circuits for them are very inexpensive.

Digikey has for sale crystal oscillators that can be programmed for most
any frequency for around 2 to 3 dollars. I have even ordered them
already programmed for about $ 4 each. I am sure in quanties of
thousnads from the manufactor they are very inexpensive.

If the processor itself is timed from a crystal many uPs give the option
of scaling down the system clock via a hardware divider to generate a
reference clock for whatever purpose u need

 

[bitrex]

On 3/20/19 6:57 AM, J.B. Wood wrote:

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,

Why is frequency stability important in a consumer-grade generator? It's
important for generators that connect to the grid because they have to
sync up to the grid. Most consumer grade generators are not designed to
connect to the grid so what's wrong with 60 hz plus or minus a hz or
two. An RC oscillator can do that. Nowadays most microprocessors have at
least one general-purpose integrated RC clock oscillator.

Appliances that use the 60Hz wall voltage for a timebase for anything
don't really exist anymore not even cheap digital alarm clocks.

 

On Friday, 22 March 2019 21:45:47 UTC, bitrex wrote:

On 3/20/19 6:57 AM, J.B. Wood wrote:

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,

Why is frequency stability important in a consumer-grade generator? It's
important for generators that connect to the grid because they have to
sync up to the grid. Most consumer grade generators are not designed to
connect to the grid so what's wrong with 60 hz plus or minus a hz or
two. An RC oscillator can do that. Nowadays most microprocessors have at
least one general-purpose integrated RC clock oscillator.

Appliances that use the 60Hz wall voltage for a timebase for anything
don't really exist anymore not even cheap digital alarm clocks.

There is one appliance fwiw, the pin or segment timer. But portable generators & electrical precision are alien concepts.


NT

 

[Fox's Mercantile]

On 3/22/19 4:45 PM, bitrex wrote:

Why is frequency stability important in a consumer-grade generator?

Obviously, you've never seen a ferro-resonant line conditioner set
fire to itself because it was running on 60 Hz.

This was a very real problem with remote radio sites, running on a
generator with Motorola Micro stations.

--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Ralph Mowery]

In article <cIclE.40169$cR2.11500@fx22.iad>, user@example.net says...

Why is frequency stability important in a consumer-grade generator? It's
important for generators that connect to the grid because they have to
sync up to the grid. Most consumer grade generators are not designed to
connect to the grid so what's wrong with 60 hz plus or minus a hz or
two. An RC oscillator can do that. Nowadays most microprocessors have at
least one general-purpose integrated RC clock oscillator.

Appliances that use the 60Hz wall voltage for a timebase for anything
don't really exist anymore not even cheap digital alarm clocks.

Most home devices not counting clocks are not that frequency sensitive.
The main thing is the simple generator must run close to 3600 rpm to
generate the desired voltage which is also generated at 60 hz.
A few cycles one way or the other does not mater, but the voltage might.

 

[Ralph Mowery]

In article <502gmf-3ne.ln1@coop.radagast.org>, dplatt@coop.radagast.org
says...

$ 10 to 20 is inexpensive for a special made crystal now. I only know
of 2 places right now, Bomar that last report was $ 50 per crystal and
minimum of $ 100 for an order. Another in England that is I think about
$ 30 per crystal.

Those programmable-frequency oscillators may have distinctly worse
phase-noise characteristics than a real crystal in a good oscillator
circuit. They may not necessarily be suitable for communications
projects or others that are sensitive to phase noise / jitter.

They are 'dirty' compaired to a crystal. I have played with a couple on
a spectrum analizer just to see.

Probably not very useful if a clean signal is desired, but fine if just
a close frequency is needed for things like a microprocessor clock.

 

[bitrex]

On 3/22/19 7:30 PM, Ralph Mowery wrote:

In article <cIclE.40169$cR2.11500@fx22.iad>, user@example.net says...

Why is frequency stability important in a consumer-grade generator? It's
important for generators that connect to the grid because they have to
sync up to the grid. Most consumer grade generators are not designed to
connect to the grid so what's wrong with 60 hz plus or minus a hz or
two. An RC oscillator can do that. Nowadays most microprocessors have at
least one general-purpose integrated RC clock oscillator.

Appliances that use the 60Hz wall voltage for a timebase for anything
don't really exist anymore not even cheap digital alarm clocks.



Most home devices not counting clocks are not that frequency sensitive.
The main thing is the simple generator must run close to 3600 rpm to
generate the desired voltage which is also generated at 60 hz.
A few cycles one way or the other does not mater, but the voltage might.

I don't think most modern consumer portable generators operate that way,
the engine and drivetrain spin at whatever rpm is convenient for the
form-factor vs. output power vs. noise level requirements etc. and it's
converted to DC then chopped and converted to line frequency AC again as
in a car battery inverter-type dealie.

 

[Ralph Mowery]

In article <cOglE.149856$j75.6445@fx36.iad>, user@example.net says...

Most home devices not counting clocks are not that frequency sensitive.
The main thing is the simple generator must run close to 3600 rpm to
generate the desired voltage which is also generated at 60 hz.
A few cycles one way or the other does not mater, but the voltage might.


I don't think most modern consumer portable generators operate that way,
the engine and drivetrain spin at whatever rpm is convenient for the
form-factor vs. output power vs. noise level requirements etc. and it's
converted to DC then chopped and converted to line frequency AC again as
in a car battery inverter-type dealie.

Most home portable generators are direct drive from the engine. They
are less expensive than the inverter type. The inverter type engines
run at whatever rpm it takes to produce the power for the inverter part.

The speed control for them is a simple goveror set for 3600 rpm. I have
two of them rated around 5 kw and one of the $89 Harbor Freight ones
that operate that way.

 

On Friday, 22 March 2019 22:58:05 UTC, Fox's Mercantile wrote:

On 3/22/19 4:45 PM, bitrex wrote:
Why is frequency stability important in a consumer-grade generator?


Obviously, you've never seen a ferro-resonant line conditioner set
fire to itself because it was running on 60 Hz.

This was a very real problem with remote radio sites, running on a
generator with Motorola Micro stations.

CVTs are obsolete and not used in homes anyway. That some things don't always survive portable gen power is not news. Portable gens have never had accurate frequency control, or accurate anything control.


NT