Growatt 3000TL LVM 48P-AC output wire size

[jkb458]

My unit is the 48V.
The manual of this Growatt specifies 8 gauge for the AC output. Does it matter how long of a run that is? My distance between the unit and the breaker box will be about 260 feet.
My panels are going into a Watts247 combiner box, then into the Growatt. Does the combiner box satisfy the requirement for a breaker between the pv and the Growatt?
Could someone please recommend wire size and type for the run from the Growatt to the breaker box? It will be buried, in pvc conduit.

https://watts247.com/manuals/gw/Growatt%20SPF%203000TL%20LVM%20Series%20User%20Manual.pdf

 

[DThames]

You might look at this wire size calculator. 3000w output / 120v is 25 amps, when running at 3000w. I am not sure if you ever plan to add another inverter (for more watts) but if you do, your wire size should be for your future state or you should plan to pull another wire in your conduit. Looks like a 5% loss of 120v would give you 114v at 25 amps, using 6 gauge copper. If you plan to be under 3000w most of the time, 6 gauge would be okay. If you plan to run close to 3000w a lot, 4 gauge would be better.

I guess the inverter and battery at/near the breaker box is not an option? If it was, a different unit that would take 250v or even 450v PV input would allow for much smaller wire size on your long run.

 

[jkb458]

Would it it be better to have the inverter and batteries near the breaker box? I thought I would be making it worse to have such a long run from the combiner box to the inverter.

 

[DThames]

Would it it be better to have the inverter and batteries near the breaker box? I thought I would be making it worse to have such a long run from the combiner box to the inverter.

It really depends on the invert's max PV input. Some of the 5000watt range newer units will take up to 450v input. For those types, you can get by with smaller wire for your long run and wire is expensive. But if for some reason you are forced to a 150v input, it won't make a lot of difference if you are running your PV or your AC that long run.

 

[jkb458]

Is this type of wire appropriate?

Southwire (By-the-Foot) 4 Red Stranded CU SIMpull THHN Wire 20498299 - The Home Depot

Southwire type THHN or THWN-2 conductors are primarily used in conduit and cable trays for services, feeders, and branch circuits in commercial or industrial applications as specified in the NEC 2. When

www.homedepot.com

 

[mopat]

Is this type of wire appropriate?

Southwire (By-the-Foot) 4 Red Stranded CU SIMpull THHN Wire 20498299 - The Home Depot

Southwire type THHN or THWN-2 conductors are primarily used in conduit and cable trays for services, feeders, and branch circuits in commercial or industrial applications as specified in the NEC 2. When

www.homedepot.com

I would probably us a 8 awg wire with a UF rating since it is buried.

8/2 Underground Feeder Cable UF-B Copper 600V( Reduced Coil Price of 125ft Coil )

Specifications : Size AWG : 8, Weight per 1,000 ft : 222 lbs, Outside Diameter : 678X302, Conductors : 2, Number of Strands : 7, Jacket : PVC, Insulation and Jacket Thickness : 35 mils, Jacket Thickness : 45 mils, Ground Size : 8. Standards : ASTM - B3, B-8, UL Standard 83, Federal Specification...

nassaunationalcable.com

 

[jkb458]

This might be a ridiculous question...where would the ground wire go? (the 8/2 wire noted above) There is only a positive and a negative port for the PV input.
I just want to be sure this will work before I order the wire. Thanks for your patience everyone....

 

[mopat]

In your original post (I thought) you were asking about AC output wiring.

Now you seem to be asking about PV input wiring:

where would the ground wire go? (the 8/2 wire noted above) There is only a positive and a negative port for the PV input.

Sorry you've confused me but if you're still asking about AC output wiring the ground wire would go here:

 

[parkswithpoints]

My unit is the 48V.
The manual of this Growatt specifies 8 gauge for the AC output. Does it matter how long of a run that is? My distance between the unit and the breaker box will be about 260 feet.
My panels are going into a Watts247 combiner box, then into the Growatt. Does the combiner box satisfy the requirement for a breaker between the pv and the Growatt?
Could someone please recommend wire size and type for the run from the Growatt to the breaker box? It will be buried, in pvc conduit.

https://watts247.com/manuals/gw/Growatt%20SPF%203000TL%20LVM%20Series%20User%20Manual.pdf

By chance do you remember what Conduit size works in the holes in the bottom of the unit?

 

[jkb458]

I don't think I've seen an installation with the conduit actually being put all the way into the unit. Just close to it, then the wire is put through. I'm not sure that conduit would fit into the openings. The holes for the PV and DC inputs are about 1 1/2".

 

[SniperX]

My unit is the 48V.
The manual of this Growatt specifies 8 gauge for the AC output. Does it matter how long of a run that is? My distance between the unit and the breaker box will be about 260 feet.
My panels are going into a Watts247 combiner box, then into the Growatt. Does the combiner box satisfy the requirement for a breaker between the pv and the Growatt?
Could someone please recommend wire size and type for the run from the Growatt to the breaker box? It will be buried, in pvc conduit.

https://watts247.com/manuals/gw/Growatt%20SPF%203000TL%20LVM%20Series%20User%20Manual.pdf

What size PV wire are you going to use?

 

[x98myers7]

24v unit here

the manual says 8ga and doesn't specify length, so I'm sure that will be sufficient. if you plan to run consistently heavy loads, you're going to want 6ga

THWN or XHHW wet rated for underground is critical. THHN is not sufficient. you could always run 6/2 romex to a junction box in the garage, then 6/2 MC or separate wires from there.

Cerrowire Resources - Ampacity Charts

Ampacity is the maximum current that a conductor can carry continuously under the conditions of use without exceeding its temperature rating. Cerrowire's ampacity chart helps calculate the load requirement for a circuit.

www.cerrowire.com

 

[x98myers7]

I don't think I've seen an installation with the conduit actually being put all the way into the unit. Just close to it, then the wire is put through. I'm not sure that conduit would fit into the openings. The holes for the PV and DC inputs are about 1 1/2".

correct, the LVM does not have provision for conduit connections

 

[SniperX]

24v unit here

the manual says 8ga and doesn't specify length, so I'm sure that will be sufficient. if you plan to run consistently heavy loads, you're going to want 6ga

THWN or XHHW wet rated for underground is critical. THHN is not sufficient. you could always run 6/2 romex to a junction box in the garage, then 6/2 MC or separate wires from there.

Cerrowire Resources - Ampacity Charts

Ampacity is the maximum current that a conductor can carry continuously under the conditions of use without exceeding its temperature rating. Cerrowire's ampacity chart helps calculate the load requirement for a circuit.

www.cerrowire.com

Thanks. That is very helpful.