110 vac vs 115 vac vs 120 vac

[3500SRW Cummins 3120RL]

Thank you BB_TX!!!! I haven’t heard hole flow discussion for 45 years when I was in school. Spent a 36 year career in electrical controls of a public utility.

[BB_TX]

Originally Posted by Jamesb

Dang 340v peak to peak? I hope you not in the US.

340v peak to peak is correct. It is about 170v from zero to peak for each half of the sign wave. So 340v from positive peak to negative peak.

[6t7gto]

https://youtu.be/iX3kxAA2L4Q

[BB_TX]

Originally Posted by 3500SRW Cummins 3120RL

Thank you BB_TX!!!! I haven’t heard hole flow discussion for 45 years when I was in school. Spent a 36 year career in electrical controls of a public utility.

College was the last time I heard it. One of those theory type things that once taught the concept, you can forget it.

I designed a lot of burner management systems for power plants and paper mills. We may have crossed paths along the way.

[JABURKHOLDER]

Originally Posted by BB_TX

Electrons have a negative charge and actually flow from the negative power terminal to the positive power terminal! Holes flow from the positive terminal to the negative terminal. What is a "hole"? When a voltage is applied to a circuit, those little electrons get excited, start jiggling, and electrons in the outer layer of an atom (those with a weaker magnetic attraction to the positive core) will break free, leaving a hole in that atom structure. That hole leaves an opening for an electron from a nearby atom to jump from its atom to that atom. An electron needs a nearby hole to be able to move. That action cascades until lots of those little guys start jumping from atom to atom ending up traveling from the negative power terminal to the positive power terminal and creating current flow. And since the electrons are traveling from negative to positive, the holes left behind are traveling from positive to negative. One is called electron flow, and the other called hole flow. Hole flow is what is thought of as conventional current flow since it flows from positive to negative. Doesn't really matter unless you are into semi conductor theory. And even I am not in that deep.
Now I will go back and hide.

WOW I haven’t heard anybody discuss “hole flow” since 1974. I was going through electronics school in the Navy before becoming an Aviation Electronics Technician.

I also learned “twinkle, twinkle little star, E = I x R

[RETCHIEF]

Originally Posted by BB_TX

Now you are getting into something I am not too familiar with. I know square wave power will work for resistive loads and some motors. But it can damage other more sensitive devices. Sine wave is a much better option.

I knew this post was going to generate a lot of discussion. But what else is there to do with the weather too cold to get out and otherwise occupy yourself?

But while we are having fun, lets talk about current flow. We all understand that current flow is those little electrons flowing thru a wire. And that is true. And we all think of current flow as those electrons flowing from the positive terminal to the negative terminal. And that is false.

Atoms (in this case making up the metal wire) are made up of a positive charged center composed of protons and neutrons, and negatively charged electrons orbiting around that center (something like moons around a planet).

Electrons have a negative charge and actually flow from the negative power terminal to the positive power terminal! Holes flow from the positive terminal to the negative terminal. What is a "hole"? When a voltage is applied to a circuit, those little electrons get excited, start jiggling, and electrons in the outer layer of an atom (those with a weaker magnetic attraction to the positive core) will break free, leaving a hole in that atom structure. That hole leaves an opening for an electron from a nearby atom to jump from its atom to that atom. An electron needs a nearby hole to be able to move. That action cascades until lots of those little guys start jumping from atom to atom ending up traveling from the negative power terminal to the positive power terminal and creating current flow. And since the electrons are traveling from negative to positive, the holes left behind are traveling from positive to negative. One is called electron flow, and the other called hole flow. Hole flow is what is thought of as conventional current flow since it flows from positive to negative. Doesn't really matter unless you are into semi conductor theory. And even I am not in that deep.
Now I will go back and hide.

My first assignment after a 52 week USAF tech school was to Patrick AFB, to support the Gemini program. We were just getting into Solid State devices and took courses on how transistors worked. This was 1965 and it was an honor to be there and learning the latest technology. I absorbed it like a free buffet. My comfort with digital electronics served me well throughout my career. Being part of Gemini, Apollo, Voyager, Skylab, and the space program opened up the eyes of a young airman, me. Too bad it is all block diagram now that component theory is no longer needed. Hole theory, Tunnel and Zener diodes, SCRs, inductive and capacitive reactance are all cave drawings now and that's sad.

[jrsemrad]

I’m old, probably about your age and I occasionally use the term 110 volts. It just shows my age, not necessarily bad. Oh by the way does the term glove box bother you also? Ha! Just fun.

[Chiefcpo]

Is it still 196Volt low end and 135 on the high side of 110/120/130 volts?
DC was what Edison used, but due to the reaction of DV voltages grabs you when touched and AC voltage repells (makes you jerk away) is why the power is considered dirty being converted from it natural polarity of DC. If I still remember my electrical course in 1966.

[JimKrieger]

In my Montana World, it's easy to learn something every day.

[BB_TX]

Originally Posted by Chiefcpo

Is it still 196Volt low end and 135 on the high side of 110/120/130 volts?
.........

It is about 170 vac on both the high and low parts of the sine wave.

[mazboy]

To much information, sorry, a non issue as far as i'm concerned. this will confuse lots of people. Just plug it in.

[Falcon]

Originally Posted by BB_TX

...... Hole flow is what is thought of as conventional current flow since it flows from positive to negative. Doesn't really matter unless you are into semi conductor theory. And even I am not in that deep.
Now I will go back and hide.

Yes! Electron theory! The theory also states that electrons only travel on the surface of a conductor. You can't prove it because once you cut into a conductor, you've got a new surface! It's kind of like my cousin who said all watermelons are white inside until you cut them open and the air turns them red. 😆

[mlh]

Bill you haft to explain thanks sine wave. I thought it was 120 volts now you say 170 volts what gives?
Thanks Lynwood

[BB_TX]

Originally Posted by mlh

Bill you haft to explain thanks sine wave. I thought it was 120 volts now you say 170 volts what gives?
Thanks Lynwood

Technically it is 120 RMS, or root mean square, and is a way of calculating the effective voltage. The first half of the sine wave goes in a positive direction followed by the second half of the sign wave going negative. A plot of current would show a similar curve. Simply averaging the two halves of the sine wave would give a result of zero even though there is power generated by that voltage and current. The full explanation of the calculation gets into calculus, not one of my better subjects.

The voltage rises from zero to ~170 volts over the first upward half of the sine wave, or about a time of about 4 milliseconds. Then descends back to zero in the next 4 milliseconds. That is one half the sine wave, the positive half. Similarly, the voltage does the same in the second, or negative, half of the sine wave. A full sine wave, then, is something over 16 milliseconds. So the voltage is 170 volts for only an instant, and much less most of the time. Ultimately the RMS calculation is the voltage at which a DC voltage would provide the same amount of power thru a resistive load.

Those little electrons (and holes) must go crazy zipping back and forth every 16 milliseconds and ending up right where they started.

As mentioned above, a DC voltage will grab you and hold on. Since an AC voltage is actually zero volts each time it crosses zero on the curve, it MAY allow a person to break free. That’s why DC is considered the more dangerous voltage. And why Edison ultimately lost out to Westinghouse.

[mlh]

Thanks Bill
Now I’m getting an education. I wired my shop single and three phase and built a single to three phase converter but I don’t know how it works. My converter does work. My three phase equipment runs. Could you please explain how a 3 phase converter works.
I remember when I was a kid asking my father why a million times. I just like knowing how things work.
Lynwood

[BB_TX]

Originally Posted by mlh

Thanks Bill
Now I’m getting an education. I wired my shop single and three phase and built a single to three phase converter but I don’t know how it works. My converter does work. My three phase equipment runs. Could you please explain how a 3 phase converter works.
................

Now we need someone well versed in the power side of electrical engineering to jump in. I went the electronics direction. Like hole flow theory, the last I remember of three phase was in college classes. About the only thing I know about three phase is that even though you do get 120 vac from it, you only get 208 vac from it rather than 240 vac.

[rohrmann]

First, all this information goes way beyond what anyone really needs on this thread.

Three phase can be 208Y/120 volts or 120/240 volts, depending on the source being a Y transformer bank or Delta transformer bank. They will both have 120 volt hot legs, two legs of 120 volts on the Delta or three legs of 120 volts on the Y. On our trailers, all we care about is the part of the transformer bank that provides the 120/240 volts, or with a Y transformer bank, any side of the bank with two 120 volt legs and the 208 volts is measured between any two hot legs, because we are not using anything but the 120 volt legs. The photo below is the sticker that came on our trailer next to the shore cord connector at the rear of the rig.

[Nighthawk]

This has been/is a most interesting and especially entertaining discussion. We have a power surge protector I hard wired into our 3400RL and it has paid us unknown dividends. A few years ago we wanted to camp overnight in Chicken, Alaska. A lot of RV Parks and businesses use generators for their power as they are located well off the grid.

We registered and went to our site and levelled off. Plugged in the power and didn't get anything in the RV. The surge protector said it didn't like the low voltage coming out of the pedestal and wouldn't give me power into the RV.

Went to the park manager/maintenance and they confirmed their generator was only providing 104 volts. I got my money back and we moved on.

And I really wanted to stay overnight in Chicken. Now in hindsight, I could have dry camped overnight. Now I think of it!!! Dummy!!!

[DebNJim B]

Correct that Edison used DC voltage in his light bulb. It was Tesla that won the AC-DC battle. AC was needed to transform the voltage higher for transmission lines and reduce voltage drop over long distances. If you think of electricity in terms of a water pipe it makes more sense. Voltage is the pressure as in 50psi and 100psi, and amperage is the flow as in 5 g/m. The electrons don't actually flow thru the pipe, they just go a bit in one direction then back in the other direction 60 times per second creating a potential as the current alternates from positive to negative.
I'm not an electrical engineer but I did work in the first building Edison bought when he formed General Electric so some of the history rubbed off. The Edison/Tesla battle is a fascinating story.

[Dave W]

Originally Posted by DebNJim B

I'm not an electrical engineer but I did work in the first building Edison bought when he formed General Electric so some of the history rubbed off. The Edison/Tesla battle is a fascinating story.

You and I probably not only passed but may have worked in the same buildings for the same group

Actually there were two original buildings, 10 and 12 (motor/gen coils) and I worked in 12 and a bunch more in my 42 years there. Both are now either parking or part of the green space GE created when they sealed and covered that polluted ground along with the 3 Zone parking lot in the late '80s to mid '90s.



Yes, Tesla advocated AC and ceated a major rift between him and Edison and Steinmetx though Westinghouse made it happen