Batrium SMA Sunny Island Integration issue?

[callmeburton]

This is preliminary but trying to rule some issues out if others have or have not had them. Feedback and testing suggestions welcome.

Issue: Load shed relay tripping off then immediately back on

• The SMA SI shows LoBatMod1 warning in the logs, this is set to 25% SOC as start and 29% SOC end, this happens seemingly randomly at any SOC > 29%
• This will trip Relay 2 OFF for a second then back ON at random occasions. ( which is a problem as it is connected to the load shed relay )
• The SMA is at a state of Battery > Loads only for this condition, but it has done it with Grid > Battery > Loads as well where Grid is connected to AC2

Setup: (full wire diagram here https://diysolarforum.com/threads/i...bank-and-sma-si-load-center.52698/post-687216 )

• Batrium WatchmonCore > SMA SI
• Batrium WatchmonCore powered by 24vdc
• Double shielded CAT8 cable connecting the High / Low / Ground pins to the Core module to the SMA COM port

Looking at the logs I can see on the batrium at no point during the suggested time frames in the SMA SI logs did the SOC drop bellow the indicated levels which would trip Relay2. I don't see any com logs on the batrium which might indicate a lack of information being sent. I have not tested what would happen if I disconnected the coms cable while the SMA SI is running to rule out physical connection issues.

 

[callmeburton]

As a side note / thought I just had ...
Technically I could migrate the load shed function to use the Batrium Expansion board relays as a SoC limit / range but I want the SI to ideally control the load shed relays.

The wiring would likely go
SMA SI Bat + (4 pin connector) > Batrium Exp Relay > load shed relay > SMA SI Bat - (4 pin connector)

This way at least the loads wouldn't be active when the SI isn't on.

 

[ChrisFullPower]

Very interesting. Unfortunately I don’t have much insight. Im currently in the (very long) process of building my Batrium / SI system and have only had it running briefly for testing and haven’t experienced any issues like this, granted I'm not using the load shedding function.

I do like your idea of moving control to the batrium though.

 

[callmeburton]

UPDATE: ... rewired the load shed to the Batrium from the SI Relay2 circuit. This will help me rule out issues with the BMS vs issues with the SI receiving or perceiving the signal. Updated wire diagram here https://diysolarforum.com/threads/i...bank-and-sma-si-load-center.52698/post-707395

Looking at the integration diagram it doesn't show the ground pin connected on the Coms cable to the SI but it has a terminal to connect it and indicates the pin on the SI side of the connector. On my setup it is connected ... I didn't see any harm in doing this and I am debating removing the pin to see what happens.

This morning the SI tripped the load breaker twice in 10 minutes, no loads, no ac in, just connected to the BMS / Battery. Current logs indicate the low soc "comes" and then "leaves" 1 second later. I can't find any logs in the Batrium right now which would indicate there is a SoC signal issue. The Daily Session also shows SoC above the threshold and it is like "king" of what was recorded that day.

 

[callmeburton]

I do like your idea of moving control to the batrium though.

There are likely more benefits to have the SI control the load shed relay(s) ... the Batrium doesn't allow granular programming of their relays which is frustrating. On the SI you can set time of days certain rules are in place if I recall correctly ... with the batrium you are stuck with system level events, pre programed options, etc ... full list here. https://wiki.batrium.com/toolkit/hardware/expansion

There are several ways I think the Batrium could be made better to be more on par with the SI options.

1. Time specific rules
2. Allow the inputs to be used for things other than system wide events. A general "is this signal there" rule where you could use that signal in and adjust a relay to do something would be nice.
3. Full simulation of a multifunction relay ... seriously ... it can't be too hard to allow a user to adjust a relay to act like a multifunction relay vs having them buy another relay to hook your relay to. Or maybe buy 2 relays in the case they want to do something different when the signal is there vs not there. :/

Also the Batrium is not AC aware ... it doesn't know when the SI is having issues and need to shed loads; that is likely the biggest issue with the SI not having this control.

 

[callmeburton]

UPDATE: was just re-re-reading the Batrium documentation ... I think my com cable is indeed not setup right.

1. the ground wire is not connected on the batrium picture of the current watchmon core I have
2. I don't have a 120ohm resistor between Hi and Lo on the com cable >__< (going to go hunt for one now as I know I have a lot of different resistors from other projects)

Not sure if either of these will be the issue but excited to try the modifications ... not too excited about reverting my wiring of the multifunction relays as it is hard to get in there right now.

 

[callmeburton]

1. the ground wire is not connected on the batrium picture of the current watchmon core I have
2. I don't have a 120ohm resistor between Hi and Lo on the com cable >__< (going to go hunt for one now as I know I have a lot of different resistors from other projects)

So the board itself has a 120ohm built right on it now ... spent 10 minutes looking for one hand was screwing it in when I realized it :/
The ground wire is now removed though so we will see what the logs do. Still have the load shed setup on the batrium expansion board

 

[ChrisFullPower]

Not sure how well versed you are in tech stuff but you may want to look into Home Assistant. It’s a very powerful home automation platform that may help in situations like yours.

Both the Sunny Island and Batrium just relay their information to it and Home Assistant controls all the logic and the contactor(s) that shed your loads.

It also has the benefit of being able to “softly” control your loads. Rather than just opening a contactor to kill power downstream, if your loads have a Home Assistant Intigration, you can simply tell them to turn off.

For instance, three of my heaviest loads are in Home Assistant (thermostat, water heater, car charger) and I can control them that way.

 

[callmeburton]

I was going to code up some pi's and Arduinos to do stuff like that ... I am a developer so doing it isn't too hard .. this might be an option though I likely wouldn't give it access to the internet.

I don't see the documentation where the batrium can be setup on the Home assistant, do you have an example of this?
EDIT: found this https://community.home-assistant.io/t/batrium-ha-intergration/316039/14

 

[ChrisFullPower]

For Batrium:

GitHub - Batrium/WatchMonUdpListener: WatchMon UDP Binary Listener translates to JSON and stores to influxdb

WatchMon UDP Binary Listener translates to JSON and stores to influxdb - Batrium/WatchMonUdpListener

github.com

For the Sunny Islands:

GitHub - pkwagner/yasdi2mqtt: MQTT adapter for SMA YASDI inverters

MQTT adapter for SMA YASDI inverters. Contribute to pkwagner/yasdi2mqtt development by creating an account on GitHub.

github.com

The current SMA integration for Home Assistant uses modbus annd unfortunately the US version of the Sunny Islands doesn’t have that capability. Luckily SMA released a API to communicate with their older inverters.

Both of those projects use MQTT and Home Assistant works natively with MQTT (once you have a server/broker set up).

 

[callmeburton]

EOD UPDATE:
I continue to hear the SI relay trip on occasion but the batrium controlled relay has not tripped at all ...
So now I am debating remaking the coms wire ... or rerouting it. The ground being connected apparently wasn't an issue and is recommended for longer runs of cable.

 

[callmeburton]

UPDATE:
Removed AC last night to let the cells discharge a bit. Noticed cell 1 (neg) was bouncing between 3.02 and 3.27 ... so I went to swap out the K9 unit and double checked the torque on the battery nuts ... the negative was super loose ... no clue how that happen ...
Put the original k9 I just took out back in and testing stuff now.

Going to keep an eye on that nut ... my cables might be setup in such a way that the cycles cause that nut to loosen up ... might need some Loctite lol

Likely unrelated but still ... I just pulled the logs to review them, several XW01General errors (BMS error) with two External BMS timeouts, and 4 lowbatSoC warnings ... We will see if that smooths out after today or not.

When I had this system charging fine the lowbatsoc was still an issue so I suspect it will continue to be an issue.

 

[callmeburton]

UPDATE:
Battery has been top balanced an issues revolving around a loose wire did not fix the coms issue with the SI. It is still receiving low soc and external bms timeouts.

I have not reduced the length of the coms cable (currently 5ft) but this morning I migrated it away from all other wires and plugged it in a little differently to see if anything changes.

 

[SilverbackMP]

For Batrium:

GitHub - Batrium/WatchMonUdpListener: WatchMon UDP Binary Listener translates to JSON and stores to influxdb

WatchMon UDP Binary Listener translates to JSON and stores to influxdb - Batrium/WatchMonUdpListener

github.com

For the Sunny Islands:

GitHub - pkwagner/yasdi2mqtt: MQTT adapter for SMA YASDI inverters

MQTT adapter for SMA YASDI inverters. Contribute to pkwagner/yasdi2mqtt development by creating an account on GitHub.

github.com

The current SMA integration for Home Assistant uses modbus annd unfortunately the US version of the Sunny Islands doesn’t have that capability. Luckily SMA released a API to communicate with their older inverters.

Both of those projects use MQTT and Home Assistant works natively with MQTT (once you have a server/broker set up).

So that github script will allow communications with US versions? If so, this is a game changer (for me anyway, I hate, hate, hate, hate web portals and I am setting up at least four servers for VLAN segregation). Not big on IOT devices/HA. Would be bit bigger on some of it, if they had more wifi/POE devices. But for things like this? That will be great!

 

[ChrisFullPower]

Correct! You can configure the inverter with Yasdi and then monitor it with yasdi2mqtt. You don’t even have to run home assistant if you don’t want to, run whatever you like that uses MQTT.

I’d suggest reading through this thread:

Sunny Webbox RS485 w/SMA 6048-US

I intend to create a big write-up in the future, but I'm still in the middle of my offgrid journey, so I'll save it for a little later once I have better conclusions. Today I just wanted to write a few notes about using the Sunny Webbox with my 2Phase2 6048-US system. This is information that...

diysolarforum.com

 

[SilverbackMP]

Correct! You can configure the inverter with Yasdi and then monitor it with yasdi2mqtt. You don’t even have to run home assistant if you don’t want to, run whatever you like that uses MQTT.

I’d suggest reading through this thread:

Sunny Webbox RS485 w/SMA 6048-US

I intend to create a big write-up in the future, but I'm still in the middle of my offgrid journey, so I'll save it for a little later once I have better conclusions. Today I just wanted to write a few notes about using the Sunny Webbox with my 2Phase2 6048-US system. This is information that...

diysolarforum.com

Awesome. I don't have nothing against HA itself. I just don't want to be the guy with 300 Zigbee and Z-Wave light switches and 85 hubs lol - that I and have multiple outbuildings, houses, and workshops that I need to cover which would be nightmare. I think about it and then watch some folks on YouTube and think "why over complicate my life?" Especially when Linus pops up.

I'm going with a dedicated Synology unit for cameras for ease of use so I'm not messing around with roll your own solutions or NVRs that want to call home.

Wish I could find alarm listeners that were POE or wifi and I would be good.

Basically a "home lab" that's going to be put to use for both business (YouTube mostly, my business involves purely written information sites right now) and home and I'm trying to keep tinkering to a minimal. It's a means to an end, not an additional hobby.

But I digress and am hijacking this thread. And thank you for those links.

 

[callmeburton]

But I digress and am hijacking this thread. And thank you for those links.

No worries, will get more views on the thread which might lead to someone suggesting something that helps me resolve the issue.

I was looking at Official SMA Com cables and none of them look shielded ... at least not the extent a Cat 8 cable is shielded ... this is leading me to believe the BMS might be the issue BUT I have no way of seeing a log of Coms / times stamps to confirm it timing out or sending low SoC.

I will likely create another Coms cable though to see if that fixes anything ... I saved the terminal connector on the opposing side of this cable as this original was a 10ft cable I cut in half to use half for the Coms coming from the K9 to the Core module (since it requires a shielded cable as well) ... I can twist some wire up and make is more short / direct and see if anything changes.

 

[callmeburton]

UPDATE:
Logs still show issues with the CAN BUS coms ... I just remembered though I have an IXXAT USB to CAN interface which I use to use to program my sevcon controller on my electric motorcycle ... I am wondering if I can find some software now which can just log all traffic for a day so I can look at them later to see if it is the BMS or the SMA or cable etc.

 

[callmeburton]

Update
Got new software setup for the IXXAT, it is suppose to be able to read the can traffic but not seeing anything.
Using 500kBits/sec, 1200bps (confirmed set in SI this way as well), not sure about the 1 1-Bit Identifiers part of the documentation https://us.v-cdn.net/6034073/uploads/1GVSH0OE6WLD/sma-can-protocol-282-29.pdf I should add I have no clue if this is 11-bit Identifier or 1, 1-bit identifier ... there seems to be a space between the numbers which lean toward the later, if that is a "thing" in the CAN world ... the CAN > Protocol Standard is 11 bit apparently so likely have settings right just not getting readings.

Trying to figure out if any combination can read the traffic coming out of the Batrium ... In windows I have the COM port set to 1200 bps, 8 data bits, party none, stop bits 1, flow control xon / xoff ...

In the canAnalyzer app there are a lot of options ... the one that made sense

Protocol standard (tried extended and both as well)
Tx Passive
Bus Coupling Lowspeed
Bitrate 500kBits/sec

 

[ChrisFullPower]

I know it doesn’t help right now but I’m hoping within the next week or so I should have my system ready for testing. I have a canbus (https://canable.io/) to usb so I can probably see if I get similar results or at the very least run a CAN dump.