PTO Generator Question

[CobyRupert]

its not just the load, the transmission line ( or cable to your load ) has impedance values, these differ depending on the frequency and conversely then will effect load as the cable is in series with the load, problems occur when frequency shags around and can cause load fluctuations. this is the main reason electricity grids are designed with tight frequency tolerance.

What is a load fluctuation? It will turn loads on and off?

Seems like you're saying that if a household generator is running at (say: +5%: 57hz or 63hz), the change in wiring impedance will lead to problems?

No way. Not one inkling.

Plugging a load into a 50 ft 12AWG extension cord would likely have 50 times more effect on the voltage (drop) than a frequency drift. .

...now if your talking about high voltage distribution lines that run 100's or 1000's of miles, a frequency shift may noticeably change the impedance, but you'd have a lot of other problems to worry about.

 

[CobyRupert]

It IS somewhat difficult to manage loads. For starters, most people just don't know this stuff and I am not blaming them. I have all manner of generating capacity and often my lady friend does not even know that we are running on a generator. I put overload relays as used on motors on my generators that can be adjusted to suit the capacity of the generator. Then, if someone does make a mistake, the circuit simply trips out. No harm done! The BREAKERS on a generating set are NOT the same thing and you can apply loads that will fry your generator without tripping those breakers!

Wait - how can that happen? I thought generator breakers were there in order to keep the generator from frying.

They are. I'm curious too.
Unless harmonics are frying the gen..., or
Unless your breaker is a MCP, or somehow only provides (magnetic) short circuit protection and not (thermal) overload protection.
BTW, those motor overloads won't protect the circuit from a short, just an overload.

 

[buickanddeere]

I work at lots of Menonite shops. Lasers, robots, overhead cranes and somewhere a Diesel Generator spewing out carbon. Like the Indians in remote areas. Kind of piises me off.

How does the diesel gen set compare in pollution vs that of the earth痴 natural release of methane or the catalog of toxic compounds related from volcanoes, earth quakes and floods .

 

[CobyRupert]

How does the diesel gen set compare in pollution vs that of the earthç—´ natural release of methane or the catalog of toxic compounds related from volcanoes, earth quakes and floods .

Not sure about methane specifically, but regarding other greenhouse gases:
Are Volcanoes or Humans Harder on the Atmosphere? - Scientific American

"According to the U.S. Geological Survey (USGS), the world’s volcanoes, both on land and undersea, generate about 200 million tons of carbon dioxide (CO2) annually, while our automotive and industrial activities cause some 24 billion tons of CO2 emissions every year worldwide. "

That's .2/24, or less than 1% (0.8%) emitted by volcanoes compared to humans.
In other words: "Diddly or squat: diddly squat"

 

[WranglerX]

How does the diesel gen set compare in pollution vs that of the earthç—´ natural release of methane or the catalog of toxic compounds related from volcanoes, earth quakes and floods .

How about keeping it within reason we can control like Propane vs Diesel....

Dale

 

[Industrial Toys]

I mentiond it before elsewhere. Firstly the breakers must deal with start up loads which most generators cannot handle on a continuous basis. Secondly, breakers are only made in certain sizes and for obvious reasons, the next larger size is chosen. That can permit the ability to run continuous loads on a generator that it will not survive. People who don't have a clue, just keep adding stuff and think as long as it still works, they're good.

Now, let's discuss POWER FACTOR.

 

[jaydee325]

Now, let's discuss POWER FACTOR.

Capacitive load, inductive load, resistive load, VARs...

No, we do not have to go there for portable or PTO generators.:confused2:

 

[Industrial Toys]

Comon, lets. I don't even profess to understand PF!:confused2: I know there are capacitive and resistive loads but I don't fully understand how KW and KVA are related or matter.

 

[RickB]

How about keeping it within reason

Dale

Hahahahahaha.

 

[koshari]

What is a load fluctuation? It will turn loads on and off?

Seems like you're saying that if a household generator is running at (say: +5%: 57hz or 63hz), the change in wiring impedance will lead to problems?

Prolly could have been clearer, the fluctuation in load would be seen from the generator however the load as the end of the transmission line coule be unchanged. Your assumption that i are refering to transmission lines in a distribution system are correct.

When i did my hv electrical protection diplima one of the practical examples that was set up on the labvolt simulator was a scenario where a single generator was coupled to load via 2 transmission lines in parallel. Once the load and was stable and at rull load the instructor switched out one of the transmission lines.

The result of this was that the capacitive reaction of the trans lines were effectively halved instantanoisely. This meant that all of a sudden the generator saw a different load even though the actual load didnt change and the generator began to chase the perceived new load. This resulted in cycling of the speed of the generator as both the governer and the avr were both trying to get the system back tp equilibrium.

So to qualify my comment was more just explaining that sudden changes in the transline impedence can cause issues rather than choosing a different length cable to begin with.