220v conversion question

[DLB]

OK, so if I could run the motor on 60volts it would draw 30amps?

[keithw86]

Assuming the same horsepower motor, yes. If the motor had four windings (instead of two, like the typical dual-voltage motor) wired in parallel instead of series, yes. Remember 1HP ~=3D 750W (add for motor inefficiency).

[FrozenNorth]

According to Ohms's Law, yes.

Current = Volatge / Resistance, resistance is a constant given the same motor.

[J. Clarke]

If it's designed to run on 60 volts with the same power output as it gives on 120, yes.

[Tom Veatch]

Doesn't matter, it's all relative.

Tom Veatch Wichita, KS USA

[Tom Veatch]

No.

With 120, 15 amps are running through the motor. 15 amps are coming in one wire and 15 amps are going out through the other.

With 240, 7.5 amps are running through the motor. 7.5 amps coming in through one wire and 7.5 amps going out through the other.

Two wires in each case. You could almost think of it like a waterwheel, one wire pouring in the juice, one wire draining it out, and the juice spinning the motor as it goes through.

OK, OK, I said "almost". It's just an analogy. (;-)

Tom Veatch Wichita, KS USA

[Martin H. Eastburn]

To have zero volts and some current - all it takes is phase shift.

Phase angle between voltage and current is well known.

Eli the Ice Man Voltage leads current in inductive (E L I ) L is inductive ICE Current leads voltage in a capacitive circuit.

So if you attach a motor to the AC lines - The voltage will go to zero before current does......

Mart> >> >>

[Martin H. Eastburn]

[Martin H. Eastburn]

Right -

I've used 1.25" diameter of copper in a plastic cover for very high current power supplies. It was so flexible that you could wrap it about your arm. It carried hundreds of amps at -2V so the drop had to be low. The sensing lines were coiled around the length to drop the inductance and respond faster. Time can kill you and have the power supply oscillate in pulsing current.

Oh - the wire - more than 1000 strands! - and the strands were electrical copper - very pure and soft.

Mart> >>

[Robatoy]

On Sep 3, 7:27=A0pm, Tom Veatch wrote: [snipped for brevity]

But, but, but... THEN where does it go?

Oh... okay then... *smirk*

[Tom Veatch]

Well, from industrial customers, it goes back to the electric company and into their settling ponds for waste treatment and sanitizing before being recycled out to the residential customers.

Tom Veatch Wichita, KS USA

[clare]

Nope. half the current at double the voltage is the same power. Technially, on a 220 volt dedicated circuit there is no reason there has to be 2 fuses.. It's just that "american" 220 is center grounded so for safety reasons each side is fused to protect againt shorts to "ground"

[clare]

The miracle of Chinese Labour.

[clare]

If the motor was designed to run on 60 volts, yes. If you tried to run the 120 volt motor on 60, no.

[krw]

A piece of #10 wire will not be more flexible than a #12 piece of the same type. That's the point.

[krw]

I don't know why they charge so much for electricity. They get it all back.

[Lew Hodgett]

Only if you are talking about a 240V/3PH/60HZ delta configuration with one phase being tapped for the 240V.

Having said that, if you pick up a ground, you will wish there are two (2) fuses in the circuit.

AKA: 3 Wire Edison. (120/240V/1PH/60HZ)

Totally different animal.

SFWIW:

For years, the automotive industry operated the electrical control systems of factory automation machines at 120V derived from a transformer wired to the 480V/3PH/60HZ supply power.

This 120V control power was purposely NOT grounded

What they would do is connect two (2), 120V pilot lamps in series across the transformer with the intermediate wire between the lamps solidly grounded.

Under normal conditions the lamps would barely glow since they were only seeing 60V each.

If one side of the circuit picked up a ground, one of these lamps would go out and the other would go to full illumination since it was now seeing 120V.

This indicated which side had picked up a ground, but did not stop production.

The repair could be preformed on scheduled down time.

Automotive electrical control panels require a screw driver to gain access.

The only person allowed to have a screw driver was an electrician.

Thus if you made unauthorized entry into a control panel and got knocked on you ass, you probably got fired for violating company policy.

Lew