what brand PV wire is best for long run ?

[Texican]

I need pv wire for a 2 ground mount arrays

first is 150 ft distance from inverter with 2 strings at 240v voc and 17amps so thats 4 wires total of 600 ft

second array is 125 ft away with 2 strings so thats 500 ft

windy nation offers extension cables at 150 ft but the reviews all seem to think it is not the awg advertized for either the 10 or 8 awg cable

should I just buy 500 or 1000 ft spool and put a mc-4 on 1 end myself ?

voltage drop at 240v and 17amps shows under 3pct with 10 awg, under 2 pct with 8awg. I am thinking to go with 10awg to save $$

what pv wire is recommended by folks here ?

thanks

 

[LywWyr]

Are you running this in conduit ?
When you say "cable" is it a multi conductor?

 

[Texican]

Are you running this in conduit ?
When you say "cable" is it a multi conductor?

no, I meant wire, not cable, sorry. just plain old pv direct burial type wire, no conduit

 

[OffGridInTheCity]

I'd buy spools (red and black) and make the connections myself. I use Wire & Cable Your Way, have ordered about 15times over the last 3 years for my solar build out. Here's a listing of their PV https://www.wireandcableyourway.com/solar-photovoltaic-pv-wire
I find their prices mainstream (e.g. similar to Home Depot or Lowes is what I mean) over time.

 

[LywWyr]

no, I meant wire, not cable, sorry. just plain old pv direct burial type wire, no conduit

If you are going direct burial then thhn/thwn won't work because neither is rated for direct burial. Not sure if the windy nation wire you reference is direct burial rated. 10-2 ufb cable is common at most "depot" stores and is DB rated. It will have 3 conductors. If you only need 2 per run , you end up buying a wire you don't need. If you go aluminum you will need to up the size.
If you are concerned with the size of the windy nation wire, ask them for the data sheet . There should be a "circular mills" column . This is the actual size of the wire minus the insulation. The CM of # 10 copper wire is 10380. There will be a slight difference size between solid and stranded. This info is available in the nec code book

 

[Texican]

here is the data from windy nation on the 10awg, does not give circular mills.
a number of reviews have complained it is not really 10 awg

Technical Specifications​

Wire Thickness:	10 AWG
Stranding:	18
Insulation Thickness:	0.075 inches
Nominal Outer Diameter:	0.28 inches
Approximate Net Weight :	17.54 ft/lbs
Ampacity 90°C Wet/Dry:	40A
Conductors:	Fully annealed stranded bare copper per ASTM B3. Class B Stranding
Insulation Jacket:	Chemically crosslinked polyethylene

Industry Standards and Approvals:​

• UL Listed as XLP USE-2 or RHH/RHW-2 for use in grounded photovoltaic systems
• RoHS Compliant
• Wet/Dry Temperature: -40°C to 90°C

 

[再生可能 エネルギー]

Wires I'am using on the DC side:

#10 AWG between the PVs and the Combining box, (150V 12A) distance between 25 and 50 ft for each string.
#6 AWG between the Combining box and the SCC (150 V 24A) distance 150 ft.

3/4" PVC conduit between the PVs and the Combining box.
1" EMT conduit between the Combining box and the SCC.

Note: Don't forget the Ground.

 

[Mike 134]

Are there enough strands to properly make your own MC4 connections? Cables I've seen for PV use are both tinned and have about 100 strands for 10Ga wire.

 

[Hedges]

10-2 ufb cable is common at most "depot" stores and is DB rated. It will have 3 conductors. If you only need 2 per run , you end up buying a wire you don't need. If you go aluminum you will need to up the size.

Note: Don't forget the Ground.

Which that 3rd uninsulated conductor in UF takes care of.

I use rigid steel conduit, above ground and below. Flexible water-tight metal conduit where it connects to inverters. I include a ground wire.
With a water-tight junction box at the end, I connect MC pigtails, made but cutting a short MC cable in half, to connect panels.

You can use PVC.
With conduit, you can pull more wires later.

Steel is supposed to buried at least 12" deep, PVC at least 18" (in my area). Direct burial would have similar requirements. Also sand and ribbon, to alert the next guy who comes through with a trencher.

 

[timselectric]

I'd buy spools (red and black) and make the connections myself. I use Wire & Cable Your Way, have ordered about 15times over the last 3 years for my solar build out. Here's a listing of their PV https://www.wireandcableyourway.com/solar-photovoltaic-pv-wire
I find their prices mainstream (e.g. similar to Home Depot or Lowes is what I mean) over time.

Their prices are very reasonable. I've purchased a lot of mining cable from them.

 

[timselectric]

Definitely recommend conduit, and THHN wire.
Easy to replace or upgrade later.

 

[rickst29]

I'm with timselectric and hedges, only adding the condition that tim's wire should be rated THHN/THWN-2 (wet or dry locations). You will need a small waterproof box (at each array location) to connect the PV wire ends into the log wire.

At 240 volts, it's not a low voltage application. Using more expensive UF cable without conduit (which I do not recommend) requires burial at least 24" deep, and it's impossible to replace if something goes wrong. With PVC conduit, the burial depth is only 18". As Hedges described, rigid steel conduit (RMC) can be buried at even less depth in most locations.