Has anyone taken a crack at figuring out the proprietary bus signaling used by Outback's inverters, charge controllers, Mate, Hubs, etc.?
I just added a used MX-60 controller to my PV system, and would like to log its performance data to a nearby server. The only supported logging method requires an Outback Mate control panel, which can convert the proprietary Cat5/RJ-45 bus to RS-232. These aren't much cheaper than what I paid for the MX-60 itself, though, and hard to justify for such a small system, especially with no Outback inverter to take advantage of other Mate functions. Plus, the Mate would be one more unneeded parasitic load, however small (server has to stay up for other reasons, so its power's already accounted for...)
Cutting up an Ethernet cable and attaching one end to the MX-60's "MATE" port, I found
- +23V on Pins 1&2 (Orange/Orange-White pair on a 568A cable),
with pin2 (solid orange) tied to battery ground. Assuming this pair supplies
power for the MATE panel
- another +23V on Pins 3&6 (Green/Green-White), apparently isolated from the
1st power feed, with no continuity to either DC terminal
- Pins 4/5 and 7/8 (Blue and Brown pairs) appear to be idle and isolated...
assuming these were the communication lines (one pair TX, one RX, possibly
current loops or opti-isolated?), I watched for signals on a scope at either
pair, but never saw any. I didn't attach the scope probe's ground,
though, not wanting to risk damage to the port, since DC- was bonded to house
ground... so, this may not have been a valid test.
If the communication lines are truly as quiet as they seem, perhaps the MX-60 never sends anything until it sees an initialization sequence from a Mate or Hub?
Could anyone with an Outback Mate, paired with an MX *or* inverter (both use the same comm bus) take a peek at the back-and-forth electrical signaling? If I had some clues on that, and could get the MX-60 to start sending periodic data frames, as it apparently does to a MATE, setting up a microcontroller to decode the raw information shouldn't be too hard. At this point, though, I don't even know which pair to watch for signals.
Would ask about this on Outback's forums, but they'd probably tell me to just buy the Mate and be done with it... was hoping unsupported hardware hacks might be looked on more favorably here
As a fallback option, some shunts, voltage dividers and A/D's in front of the MX-60's DC inputs would probably do the job, but that seems so wasteful and redundant, when all the intrumentation's already built in.