Wiring Question

[Brazos94]

I'm purchasing the Flexboss 21 and Gridboss currently. My question is what size of wiring? My 200amp meter is on outside of house and I will be running wires underground 60ft away to my garage barn where the Flexboss, Gridboss, and Batteries will be located. So need help on what gauge of wires needed for that distance away from meter/main panel? Plus, can you run both the grid wires and load wires in the same conduit or do they need to run in separate conduits? I believe there will be 4 wires(ground, neutral, hot, hot) from meter to Gridboss in garage/barn. Then 4 wires(ground, neutral, hot, hot) from load on Flexboss to main service panel back at the house? Looking for suggestions....

 

[HRTKD]

Use a wire gauge calculator like the one linked below, which can take into account wire in conduit.

Voltage Drop Calculator | Southwire

www.southwire.com

 

[TechRider]

According to the video launch yesterday, it sounds like you may be able to install the grid boss at the house and just run a single power cable from the flexboss to the gridboss. You may want to review their recommended wiring a little closer.

 

[timselectric]

According to the video launch yesterday, it sounds like you may be able to install the grid boss at the house and just run a single power cable from the flexboss to the gridboss. You may want to review their recommended wiring a little closer.

Yes, this exactly.
this is what it's designed for.

 

[Chank80]

Hey, I'm new here too and have the same question. I'm running 200 ft between the flex boss and grid boss. I used the above calculator and it looks like 2 awg is the answer. That's also the largest you can connect at hybrid port for flex boss. It looks like the size is still 2 awg for a 60 ft run. Does it matter if it's stranded vs solid wire? Thanks in advance.

 

[timselectric]

Does it matter if it's stranded vs solid wire? Thanks in advance.

The electricity won't care either way. But #2 solid is not something that you are going to want to work with. If you could even find it, readily available.

 

[TechRider]

I just looked it up for fun... #2 solid wire is over 1/4" thick. You'd have to be a better man that me to get that through a 90° bend!

 

[PVGeezer]

If this is going to be your residential 200A service that is normally 4/0-4/0-4/0-2/0 aluminum. That is because you get a 83% multiplier on the 200A due to load diversity. You can get Edit-URD direct burial cable and you won't have to run it through conduit if you use a 24 inch bury depth.

 

[TM48]

I think you mean URD

 

[PVGeezer]

I think you mean URD

yep sorry my bad. corrected. SER isnt direct burial rated.

 

[funkzy]

Yes, this exactly.
this is what it's designed for.

Question on this - wouldn't you need two sets of wires to support a barn with solar, batteries, and loads in the barn?

One for the solar/battery input going from Flexboss -> Gridboss, and one for the loads going from Gridboss -> barn?

I checked the Gridboss wiring diagram v1.0 and the "EG4 GridBOSS Basic Architecture" diagram has a note on the inverter that says "Load Port not used w/GridBOSS", which I interpreted to mean as any loads must be powered by the Gridboss, not from the Flexboss.

Thanks for any clarification you can offer - it would be phenomenal if the Gridboss/Flexboss setup could work with a single wire set

 

[timselectric]

Question on this - wouldn't you need two sets of wires to support a barn with solar, batteries, and loads in the barn?

One for the solar/battery input going from Flexboss -> Gridboss, and one for the loads going from Gridboss -> barn?

Yes
The single set of wires is just for the flexboss to gridboss connection.

I checked the Gridboss wiring diagram v1.0 and the "EG4 GridBOSS Basic Architecture" diagram has a note on the inverter that says "Load Port not used w/GridBOSS", which I interpreted to mean as any loads must be powered by the Gridboss, not from the Flexboss.

Correct
All loads come from the Gridboss.

Thanks for any clarification you can offer - it would be phenomenal if the Gridboss/Flexboss setup could work with a single wire set

It does.
But loads are not part of that.

PS: while it's only one set of AC wires. You also need a communication cable.

 

[CaySol]

Yes
The single set of wires is just for the flexboss to gridboss connection.

Correct
All loads come from the Gridboss.

It does.
But loads are not part of that.

PS: while it's only one set of AC wires. You also need a communication cable.

Communication cable in the same conduit is a no no right?

 

[timselectric]

Communication cable in the same conduit is a no no right?

Probably, in this situation.

 

[PVGeezer]

On the separate conduit question when I put in my EG4 18ks last summer an advisor at EG4 said that there was a Code requirement that the ct cable be run through a separate conduit. I looked and couldn't find anything like that in the Code. Has anyone?

I had about a 150 ft run so I ran a separate conduit into and out of the trench for the ct cable but used direct burial power and data cables with 6 inches of soil separation in the trench. My AHJ was happy so I was too.

 

[Madcodger]

As I recall, the issue with comms wiring (e.g., for RSD) is the shielding. If in same conduit must be appropriately rated (600v in most cases). It's available but expensive compared to Cat 5/6.

 

[PVGeezer]

I understood from the EG4 conversation that it was something specific for ct wiring but I never found anything like that. He could have been mistaken and it was just the voltage rating.