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[QUOTE=Frank Pratt;3073565]Well larger motors that have a choice of either supply voltage start and run better on 230 volts. I am (was now retired) a licensed master electrician and been so since 1964. I am well aware of how to wire motors and controls, that what I did. If it was a misconception I was fooled for over many years.....Originally Posted by Bill George
. Worked with 3 and single phase motors, VFD's and controls. Ask me about Code passed tests in Minn and Iowa.
Retired Guy- Central Iowa.HVAC/R , Cloudray Galvo Fiber , -Windows 10
Member
[QUOTE=Bill George;3073583]Can you provide actual measurements of the performance parameters that are improved and by how much?
Beranek's Law:
It has been remarked that if one selects his own components, builds his own enclosure, and is convinced he has made a wise choice of design, then his own loudspeaker sounds better to him than does anyone else's loudspeaker. In this case, the frequency response of the loudspeaker seems to play only a minor part in forming a person's opinion.
L.L. Beranek, Acoustics (McGraw-Hill, New York, 1954), p.208.
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[QUOTE=Bill George;3073583]Nope, that just isn't so. The only time a motor will run better on the higher voltage is if there is excess voltage drop because of inadequate wire size. I've done a bit of study on motors & have not seen anything that would support your statement. Can you share your source?
Well larger motors that have a choice of either supply voltage start and run better on 230 volts. I am (was now retired) a licensed master electrician and been so since 1964. I am well aware of how to wire motors and controls, that what I did. If it was a misconception I was fooled for over many years.....
If you're looking at the whole installation picture, then it is better to wire a motor for the higher voltage because of reduces wiring costs associated with it. But the motor will run no better on one voltage or the other.
I'm also a master electrician, but only since around 1982, so you've got me beat there
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Over 50 years in the trade, most of which was commercial and industrial side, and design installation of controls. Last 12 years I taught the subject. Do a Google search and educate yourself. Large dual voltage single phase motors start and run better on 230 vs 115 volts.
Any real world electrician will know that, one that has worked in the trade, that is....look it up and prove me wrong.
Here is one after a 10 sec search https://www.hobby-machinist.com/thre...vs-115v.77415/
Yet another..... https://www.practicalmachinist.com/v...0-110-a-83411/
Another,,,,......>> http://jpandersonwell.com/what-elect...most-pumps.php
This is almost to easy..... https://www.powertransmission.com/is...dor-basics.pdf
Or join this forum and ask the question ??? https://www.mikeholt.com/
Last edited by Bill George; 11-27-2020 at 12:41 PM.
Retired Guy- Central Iowa.HVAC/R , Cloudray Galvo Fiber , -Windows 10
Contributor
Nope, assuming that the circuit supplying the motor is adequate, the motor will perform exactly the same on 120 volts as on 240 volts. What happens in many situations is that the 120 volt circuit cannot provide the amperage needed without a significant voltage drop and that causes the motor to perform poorly compared to operation at 240 volts. But if the circuit is adequate, performance is the same on either voltage.
Mike
[Regarding your 50 years of experience: That would be of value if you were discussing things you found in the real world. For example, if you said that most motors that were wired for 120 volts were on circuits that were not adequate for the amperage demand you would be believed. But when you try to dismiss well proven electrical theory with a claim of 50 years experience you're not going to be believed. If you want to argue that a motor operating a 240 volts performs better than if that same motor is operated at 120 volts you're going to have to provide reasons based on electrical theory and the mathematics to back it up. I don't think you're going to be able to do that.]
Last edited by Mike Henderson; 11-27-2020 at 1:58 PM.
Go into the world and do well. But more importantly, go into the world and do good.
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I am going to un follow this Thread and let you Experts keep on, I suggest you read and learn from the Links I have posted.
Retired Guy- Central Iowa.HVAC/R , Cloudray Galvo Fiber , -Windows 10
Member
I looked at those links. None of them really support your claims.
As has been stated, any perceived differences in performance are due to the infrastructure, not the motor.
Last edited by David L Morse; 11-27-2020 at 1:51 PM.
Beranek's Law:
It has been remarked that if one selects his own components, builds his own enclosure, and is convinced he has made a wise choice of design, then his own loudspeaker sounds better to him than does anyone else's loudspeaker. In this case, the frequency response of the loudspeaker seems to play only a minor part in forming a person's opinion.
L.L. Beranek, Acoustics (McGraw-Hill, New York, 1954), p.208.
Contributor
Hmm, I thought I was a real world electrician
Anyway, Bill has bailed on the thread, but I thought I'd comment on his links. There are a bunch of forum posts that talk of higher voltage installations being better for cost reasons and also "220V rules" posts from 'experts' who don't even know that there is no 220V here. The other articles talk of the benefits of higher voltage with regards to voltage drop, particularly in long circuit runs. I could find no factual information saying the the motor performs better on the higher voltage.
Over 50 years in the trade, most of which was commercial and industrial side, and design installation of controls. Last 12 years I taught the subject. Do a Google search and educate yourself. Large dual voltage single phase motors start and run better on 230 vs 115 volts.
Any real world electrician will know that, one that has worked in the trade, that is....
Contributor
I think many people believe that a motor run at 240 volts performs differently than when run at 120 volts because they've had situations where the supply circuit is not adequate at 120 volts. And sure enough - in that situation - the motor does perform better when operated at 240 volts. The mistake they make is to believe the difference in performance is due to the motor, rather than the supply circuit.
Mike
Go into the world and do well. But more importantly, go into the world and do good.
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That's exactly it Mike. There are even electricians that think that
Member
I've had a PCS with 1.75hp motor for several years but I don't think it's five yet. I run it on a 120V 20A circuit. I initially did not have any issues with it and power but when I was making a bunk bed with legs close to 3 inch square out of softwood, I had trouble with the rips. I used it to make a queen sized bed with similar sized, but shorter, softwood legs and a queen sized bed with cherry legs about 3 inches square. Until the bunk bed legs, no issues. I mainly used full kerf blades. When I started having issues with the bunk bed legs I started trying different blades. I think I had on a nearly new Infinity 50 tooth all around blade and switched to an Infinity 24 tooth rip blade, both full kerf. It didn't seem to help much. So I went to a not close to new but still serviceable Freud 24 tooth ripping blade and it cut much better. Next I tried a thin kerf Freud 24 tooth ripping blade and it cut at my normal feed rate, no issues. I think the wood was closing up on the blade a little and that was part of the issue.
I had lesser issues cutting a 1 inch thick oak tread I was recycling. The thermal overload tripped on a short and not that deep rip. But I noticed the wood was pinching the blade and put a wedge in the kerf and the issue disappeared.
I now use only thin kerf blades on my PCS. I have done some near 3 inch rips with the Freud Fusion all around blade that is on it at the moment. But I am pretty sure if I get into wood that wants to close up right after the riving knife again I will need to switch to a ripping blade. But that pinching is less likely, I believe, with the thin kerf because the thickness of the riving knife is very close to the thickness of the steel plate of the blade - closer to the kerf size. With a 1/8 kerf blade, it is easier to adjust the riving knife position but it is easier for the wood to close up despite the riving knife and pinch the blade.
I've used 110V table saws for around 50 years and I do not remember one that wanted thin kerf blades as badly as my PCS. Wiring may well be the issue but if you haven't tried a thin kerf blade I would.
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