Using 120v wire for 240v????

I just realized I may not be exactly right with my more efficient assessment. As noted earlier it by @JPMacG will have less voltage sag since amps will be about half. Also since amps are half you will have less loss through resistance in the lines and windings(translating to heat). I think that is what lends the efficiency boost.

Also it helps balance your load panel since it’s pulling from both legs.

I looked at a couple dual voltage motors and they have the same total wattage between 115 and 230.
 
Same wattage but Lower Amps at Higher Volts.....The savings in utility bill should be negligible to nonexistent.....I only klnow this stuff because I went all through it when I went solar grid tie buyback....
 
rbertalotto said:
I been thinking.....

I have a dual voltage (120/240) compressor that is some 50' from the electrical panel in my shop.

It is currently wired to 120V / 20a breaker using three 10g THHN wires in metal conduit. I used 10g simply because I have rolls of it given to me years ago.

Question....Can I use these three wires and a dual pole 20a breaker to wire it as a 240 motor?

Although it has been running for years as a 120v motor, is there an advantage to switching it to a 240v wired motor?

Thanks again...Extremely helpful forum!
Click to expand...
I would suggest you acquire a copy of Uglys, it is an electrical reference book which provides answers to this type of questions and is generally speaking, inexpensive. https://www.amazon.com/Uglys-Electr...hvlocphy=&hvtargid=pla-4584482474666837&psc=11682967215202.jpeg
 
Charles scozzari said:
No. 6 wire. The motor will run cooler and more efficiently. What is the H.P.? as for the breaker.
Click to expand...
My reasoning for overkill is simple. Now if you want to run a welder or other machine you have no problem. "Overkill" never hurt anyone
 
My reasoning for overkill is simple. Now if you want to run a welder or other machine you have no problem. "Overkill" never hurt anyone
Click to expand...

But not with a 20a circuit breaker......
 
Mill Lee farm said:
Now, won’t the total wattage draw be the same for both voltages? Is there actually money saved if he switches to 240V?

I know the wiring is cheaper because of the reduction in current draw allows smaller gauge/cheaper wire… but will his electric bill be changed? He’s already got it wired so THHN cost difference doesn’t matter
Click to expand...
No not really. Higher voltage less current ... current equals heat, equals loss. But it's not much, it can be. I know it should be equal, and I have had this argument before, and in theory it should be equal, but that heat when it gets hot from the higher current is loss. So MY HUMBLE (trying to be) is that there is a gain by using higher voltage.
 
woodchucker said:
No not really. Higher voltage less current ... current equals heat, equals loss. But it's not much, it can be. I know it should be equal, and I have had this argument before, and in theory it should be equal, but that heat when it gets hot from the higher current is loss. So MY HUMBLE (trying to be) is that there is a gain by using higher voltage.
Click to expand...
It’s why transmission lines are running up to 700k volts. Less heat carrying the same wattage
 
D.sebens said:
It’s why transmission lines are running up to 700k volts. Less heat carrying the same wattage
Click to expand...
Voltage is potential, Amps are a unit of current and watts is a measure of the work done, convertible to units such as horse power. Volts X Amps = Wattage. The reason they use the high voltage over long distance is to overcome line loss through conductor resistance which is what makes it more efficient. Essentially 220V at 10A = 2200W while 110V at 20A = 2200W, one has more potential the other has more current both produce essential the same amount of work but more current causes more resistance less efficiency. and more potential is more dangerous.... I am fairly certain that is correct.... :rolleyes:
 
You must log in or register to reply here.
Back
Top