[RE-wrenches] Sol-Ark 15K and HomeGrid - Comm Cable Pinout

[Jason Szumlanski]

Thanks Maverick. This turned out to be the answer. No ground wire was
needed.

I found out the master inverter is faulty. I connected the cable to the
slave (after unparalleling) and it worked. Sol-Ark was surprisingly very
willing to send me a new MCU board without any argument.


Jason Szumlanski
Principal Solar Designer | Florida Solar Design Group
NABCEP Certified Solar Professional (PVIP)
Florida State Certified Solar Contractor CVC56956
Florida Certified Electrical Contractor EC13013208

On Thu, Oct 16, 2025, 1:00 PM Maverick Brown via RE-wrenches <
re-wrenches at lists.re-wrenches.org> wrote:

> Jason,
>
> I have a couple working HomeGrid to Sol-Ark installs.
>
> The manual does seem to mix flavors of cable and even the cable that came
> with the HomeGrid install of 2024 has Ethernet Type A color code pin out.
>
> If you keep the pin out as type A, that is fine, but I made a chart with
> Type B wiring, attached. Also, I think you should not connect the other
> unnecessary wires on the Sol-Ark side, just to eliminate any issues.
>
> I also assume they are using CAN and not using RS485...
>
>
> Let me know how that works for you.
>
> Thank you,
>
> Maverick
>
> Maverick Brown
> Off-Grid Solar Commander since 2006
> *Maverick Solar Enterprises, Inc.*
> * • Solar Commander Remote Power*
>
> * • SunFlow Systems Cathodic Protection *maverick at mavericksolar.com
> 512-460-9825
>
> On Oct 16, 2025, at 9:27 AM, Jason Szumlanski via RE-wrenches <
> re-wrenches at lists.re-wrenches.org> wrote:
>
> Does anyone know for sure what the correct pinout is on the communication
> cables for this pairing? Sol-Ark has multiple battery integration guide
> versions.
>
> Some show two wires connected to pins four and five on the inverter and
> seven and eight on the battery, respectively. In another version of the
> guide, four is connected to eight and five is connected to seven. In yet
> another version, a green wire is introduced. I have tried all three
> combinations, and none work.
>
> I can't get a straight answer out of either manufacturer, and of course
> they're both pointing fingers at each other regarding my battery
> communication issue.
>
> Sol-Ark is sending a firmware update and recommended a factory reset.
> That's the next step, but it doesn't answer the question about the correct
> pinout.
>
>
>
> Jason Szumlanski
> Florida Solar Design Group
>
>
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