Will this DC pump work with 12/3 cable at 200' or I need 10/3

[Paltus]

https://www.amazon.com/gp/product/B07MF13KPZ

I ran it outside of the well on 250' roll of 12/3 between the controller and the pump, restricting the flow so it would pressurize to 80+PSI near the pump and it seems to be doing that. Is it a good test ?

 

[Paltus]

https://www.amazon.com/gp/product/B07MF13KPZ

I ran it outside of the well on 250' roll of 12/3 between the controller and the pump, restricting the flow so it would pressurize to 80+PSI near the pump and it seems to be doing that. Is it a good test ?

PS I also tried to run it on 250' roll of 14/3, it didnt work, the pump wouldnt start

 

[Sponsor]

 

[Valveman]

Probably need to ask the manufacturer. With long wire from an inverter I would think shielded wire would be more important than a larger size. The power from an inverter or VFD travels on the skin of the wire like a radio signal instead of the core of the wire like regular AC power. Shielded wire keeps it from loosing anything or picking up other stuff on the way to the pump.

 

[Paltus]

Probably need to ask the manufacturer. With long wire from an inverter I would think shielded wire would be more important than a larger size. The power from an inverter or VFD travels on the skin of the wire like a radio signal instead of the core of the wire like regular AC power. Shielded wire keeps it from loosing anything or picking up other stuff on the way to the pump.

thanks. The seller said 12/3 is OK. https://www.amazon.com/ask/questions/TxO1XE52MR166U/ref=ask_dp_lsw_al_hza?asin=B07MF13KPZ
I think I will be doing 12/3.

For the record I tested it on coiled 250' 12/3 NM roll that I had for non-pump electric work, and the 12/3 coil worked fine and didnt interfere with itself. 14/3 that didnt work was also NM coiled and I am now wondering whether it didnt work because it was coiled & unshielded or because the wire size is too small. but anyway 12/3 it will be, the 14/3 was more out of curiosity anyway.

 

[Reach4]

For the record I tested it on coiled 250' 12/3 NM roll that I had for non-pump electric work, and the 12/3 coil worked fine and didnt interfere with itself. 14/3 that didnt work was also NM coiled and I am now wondering whether it didnt work because it was coiled & unshielded or because the wire size is too small. but anyway 12/3 it will be, the 14/3 was more out of curiosity anyway.

Weird that it would work with 12 and not 14. Usually wire size is about wire heating rather than operating.

 

[Paltus]

Weird that it would work with 12 and not 14. Usually wire size is about wire heating rather than operating.

my theory was on 14/3 the voltage drop was too big - I could feel the pump trying to start but never starting. now another theory is also unshielded coiled cable (but I really dont know anything about that). Note it is a 24V DC pump

 

[Reach4]

my theory was on 14/3 the voltage drop was too big - I could feel the pump trying to start but never starting. now another theory is also unshielded coiled cable (but I really dont know anything about that). Note it is a 24V DC pump

This was being powered solely by solar cells?

 

[Bannerman]

Note it is a 24V DC pump

The power draw specification for that pump is 270 watts. 270 /24 = 11.25 amps but being DC, there will be greater voltage drop over 250' compared to AC power, thereby requiring larger conductors to reduce the voltage drop.

 

[Paltus]

This was being powered solely by solar cells?

for the test I was using DC power supply https://www.amazon.com/dp/B08GFSVHLS

 

[Paltus]

The power draw specification for that pump is 270 watts. 270 /24 = 11.25 amps but being DC, there will be greater voltage drop over 250' compared to AC power, thereby requiring larger conductors to reduce the voltage drop.

all true but somewhere in there I think it said for starting it needs upto 14 or 16 amp
and I measured current over UVW wires when the pump as doing 85 PSI, my meter was showing about 8 amp over each of the 3, I don't know
how they add up though