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robsbeach
Nov 14, 2009, 12:36 AM
What size wire do I need to run 150ft. And operate a24volt brushless dc motor

tkrussell
Nov 14, 2009, 05:33 AM
Need to know the amp draw of the motor to determie the size wire needed to deliver 24volts 150 feet and keep the voltage drop at an acceptable level for the motor to operate properly.

This is a decent explanation, along with a chart that you can see as the amperage increases the wire size increases at a particular distance.

http://www.securitypower.com/AN2WireTable.pdf

stanfortyman
Nov 14, 2009, 06:59 AM
It also depends on where the power supply is. I can only assume it is AT the motor, which would make it a 120v or 240v circuit (depending on the primary voltage), NOT 24v.

It would be absolutely absurd to have a power supply at the house for a (low-voltage) gate motor. Gates are regularly several hundred feet from the house/structure so the voltage drop would be astronomical.

robsbeach
Nov 14, 2009, 01:11 PM
I guess I did not word my question right, my primary voltage is 120v, that will run 150ft.at the end of the run it will operate a 24v dc gate opener motor.I'm not sure of the amp draw on that motor. I'm sure a 12/2 would work, but the instalation instructions call for a 15amp breaker. Could I use a 20amp breaker instead?

KISS
Nov 14, 2009, 07:31 PM
There is no harm in using 12/2 and a 15 A breaker.

Voltage drop calcs, says the load should be 6 amps or 6*120 watts using 12/2 at 150 feet. That will give a 3% drop.

8 AWG would be able to handle 15 A at a 3% drop.

You can pigtail 14 AWG wires to the 8 AWG at the ends if necessary.

tkrussell
Nov 15, 2009, 06:54 AM
**** Two Threads Merged*****

Very important to get complete accurate information when posting a question.