Sizing Solar Tracker DC Motor Conductor

[hill900505]

I am trying to size the conductor from inverter station to each tracker motors for the solar array. I have been reading the code book but still got some confusions. Usually, the motor used to move the tracker is 24 Volts DC motor with a rectifier that converts 240 volts AC single phase to 24V DC. The 24 volts DC is then used to power the motor. My question is:
1. The NEC 430.22 should be used to size the AC conductor not NEC 210 since this falls to sizing motor conductor?
2. The rectifier is rated for 700W, with AC input shown on the nameplate 240V, 3.6A, however the motor is only rated for 270W, do I still need to size the conductor per NEC 430.22.(A), 125% of 3.6A even though the rectifier is overkill for the 270W motor OR i need to size the ac conductor feeding the rectifier based on 270W/Efficiency/Power Factor/240volts and then times 125%? I have not seen a lot of information on the internet explaining how to size this small 24 volts motor for solar trackers.

Thanks everyone!

 

[Jraef]

The smallest field wiring you can run out of a cabinet or enclosure (without special circumstances) is 14ga per 430.22(G). Quit agonizing over trying to save $1.32 and run 14ga wire. Just the time you took typing the question likely cost you more than you might save trying to use something smaller.

 

[hill900505]

The smallest field wiring you can run out of a cabinet or enclosure (without special circumstances) is 14ga per 430.22(G). Quit agonizing over trying to save $1.32 and run 14ga wire. Just the time you took typing the question likely cost you more than you might save trying to use something smaller.

Thank you! Also, am I referencing the right code? i should use the code for sizing motor conductors instead of 210 to size the conductor?

 

[ggunn]

I am trying to size the conductor from inverter station to each tracker motors for the solar array. I have been reading the code book but still got some confusions. Usually, the motor used to move the tracker is 24 Volts DC motor with a rectifier that converts 240 volts AC single phase to 24V DC. The 24 volts DC is then used to power the motor. My question is:
1. The NEC 430.22 should be used to size the AC conductor not NEC 210 since this falls to sizing motor conductor?
2. The rectifier is rated for 700W, with AC input shown on the nameplate 240V, 3.6A, however the motor is only rated for 270W, do I still need to size the conductor per NEC 430.22.(A), 125% of 3.6A even though the rectifier is overkill for the 270W motor OR i need to size the ac conductor feeding the rectifier based on 270W/Efficiency/Power Factor/240volts and then times 125%? I have not seen a lot of information on the internet explaining how to size this small 24 volts motor for solar trackers.

Thanks everyone!

I don't know if this is relevant to your question, but in I have read that in many solar tracker systems with multiple motors it is common to install gear that ensures that all the motors do not run at the same time.