Power transfer

[muskrat]

If a cable is rated @ 100amps for 150 feet. What will be the effect if I use 300 feet. I am using 220 volts and will be running a electrical grain auger. Will there be a significant power loss. I only need a maximum of 60 amps to run the motor, will I get this if i use 300 feet of this cable?

 

[dydt]

I am making an assumption that you are going to use a 3-phase motor, rated 220 volts drawing 60 amps..

at 220v supply voltage, my calculation shows..

for 1% drop (2.2V)...you need a No.4/0 cable

for 2% drop (4.4V)..you need No.1/0 cable

for 3% drop (6.6v)..you need No.2 cable..

all calculated for 300 feet...



dydt

 

[jbartos]

Suggestion: More information is needed about the motor nameplate data and about the cable data sheet.

 

[electricpete]

What muskrat may not be aware of is that the cable ampacity (current rating) is not affected by the length of the cable.

But as y-prime pointed out, there is a voltage drop in the cable which increases with cable length.

For motor loads, this will slightly increase the current drawn by the motor in steady state. More importantly the motor will take longer to come up to speed and will heat more during starting and in severe cases may trip or stall during starting.