zak687

So I think the wake up is working as the LCD panel comes on with solar and shows that it is charging the battery but not the supplying the load. But fault mode might be the issue with respect to the load, if it requires that fault code 4 clears in addition to getting over the threshold to restart the output. That requires the voltage to be 4v higher than the low voltage cut-out for the inverter. And that is difficult to emulate without actually running the battery down.

Thanks Coulomb. Would one assume this cable is present and functional when supplied as new? In my emulation when I reconnected the solar the battery started charging and the LCD on the inverter came on showing the battery was charging, it just did not restart the output (AC).

These are the settings I am changing - the screenshot is for a 24v system, but am setting a) to 47v and b) to 52v. Have bulk, float and equalisation all set at 56v. The watchpower manual says "Back to discharge voltage: When battery voltage is higher than this setting voltage, battery will be allowed to discharge." Not sure which setting b) aligns to but probably 13? Does anyone with an off-grid setup have their system resuming unattended when sun returns?

Thanks Talia. Have some remote monitoring (this project), just not all sensors, but it is powered by the inverter and goes down when the inverter goes down. Have considred trying to manage it remotely with more effort to keep the gizmos up when the inverter is down, but would be much easier if the inverter simply came back to life when there was sun, which I was led to believe was possible. Looking for a second battery.....if anyone is flogging a Greenrich P3686, let me know!

Yes, SBU is selected (program 1) Or did you mean Program 16 - cannot reall what that is set as, but all the options in the manual suggest solar would be used?

We have a Kodak OG 5.48 inverter with a Greenrich 3.68kwh battery in a cabin, completely off-grid, just running refridgerator, wifi and self-consumption (which is surprisingly high for this inverter). After a run of cloudy days the battery was dying at a preset (battery setting) of 45v. When sun returned the system would not wake up unless the battery was power-cycled, but given cabin is unattended in the week, this was not possible. Set up with USER settings rather than pylontech (that is another story but not for now). Using Watchpower, we then tried setting the inverter to switch off at a voltage higher than the battery minimum (we set it at 47v while the battery cut-off remained at 45v) hoping the inverter would switch off but the battery stay on, so that when sun returned the inverter could resume charging the battery which would still be awake. We set the "back to discharge" voltage to 52v hoping that when the battery was being charged again, the inverter would start supplying the AC output once more when the battery reached this voltage. WIth this last run of cloudy days it worked to cut the AC output at 47v with the battery still alive, but when the sun returned the output has not started again. I am not at the inverter to see what is happening, but when I tried to emulate while on site (by disconnecting and reconnecting the solar input), I also observed that the AC output did not start again when the voltage reached the back-to-discharge voltage, unless I power-cycled the inverter. I hoped it was an anomaly in my emulation, but seems not. 1. What is the correct configuration for an off-grid implementation with this inverter which would enable it to auto-recover when sun returns? 2. Are we interpreting the back-to-discharge voltage correctly? 3. Setting the cut-out voltage higher so that the inverter cuts the output while the battery sill has some charge, can result in Fault 04 frequently occuring, as this threshold and the operative voltage are often within 4v of each other. We had wanted to set it higher than 47v, but for this fault. Thanks for the advice.

Sadly I am back to where I started. Maybe with sun lower, maybe the FW changes have been reverted to deal with the unintended consequence on the other string..... Has anyone had any success with optimizers and willing to share what they did? Alternatively, has anyone managed to get the DC connection under software control so that the cycling can be automated?

I find that there is an improvement since my original issue whether or not I tick the option in the firmware, but there is an associated problem now in the other string. I am currently querying this with Sunsynk/Deye. I was also advised that they had done all they could on the shading and that I should explore optimizers. But in fact they made a sincere effort to address the issue and got 80% of the way there, and mostly resolved my original issue, just that there is a side effect which needs to be addressed still. My production with partial shading of the one string in the morning changed from this (partial morning shading affecting the purple string): to this after a FW upgrade (see the weird impact on the blue string when the shading recedes on the purple):

Meaning I still have the shading, and output is both higher but also closer to what is expected in spite of the shading. Previously the string with the shading would produce 10x less power until the shading disappeared completely later in the day, whereas it is now closer to expected (proportionately less power in line with some bypassing due to shading). Sunsynk asked me to check twice following firmware upgrades and both times did not see an improvement (this was some weeks prior to observing the change), but otherwise claim to be still working on it.

⬇️

Has anyone with this issue noticed an improvement of late? Not sure if it is changing seasons and shading, or if one of the firmware upgrades actually made a difference, but am noticing a less dramatic differential on the shaded string than previously, during the time of partial shading. Then weirdly a difference in peak output in favour of the previously shaded string. vs this previously

I have a similar issue with the 3.686kwh Greenrich battery in an off-grid scenario with an Axpert King inverter (Kodak branded). If using the lithium settings, as it approaches 100% charge it gets into a loop of charging and then stopping, every 15 to 30s endlessly. In a small cabin it is very annoying as the inverter fans spin up and down constantly. If using the USER settings (voltage driven), this was happening as well if using the bulk and float charge voltages which were originally recommended (57v) but not if using lower voltages. Unfortunately when in BMS coms mode for Lithium or Pylontech, the BMS communicates the voltage to the inverter and even with the BMS upgrade it is still 57v. I eventually used a serial cable and monitored with PBMS tools while it was exhibiting the stop/start behaviour, and could see there that over-voltage protection was kicking in aborting each attempt at resuming charging. The battery distributors have advised that we stick to USER settings with manually configured bulk and float voltages of 56v and 55v instead of the 57v the BMS communicates to the inverter. The downside is that we lose out on the more accurate SoC reported by the battery compared to the voltage-based estimates from the inverter, which in my case are very inaccurate. Not sure ZA Moose if the discharging / charging you are seeing in BMS mode is related in any way to different voltages compared to voltage-based mode, but if you are able to find a cable and monitor the battery directly, if might assist.

Does this help? Screengrabbed from PBMS tools Maybe it is this - the ports, lights and buttons look the same as on the unit http://www.pacebms.com/en/index.php/shows/33/12.html

Thanks. Yes, we have been using USER settings, but the SoC calculated by the inverter based on voltage is then often way-off. But maybe they can release a firmware update.....

Thanks Bronwyn. So confirms the 57v comes from the BMS. With this setting when close to full charge the battery keeps cutting out due to overvoltage protection, and the inverter then tries again to charge. Stop start every few seconds for ages with fans spinning up and down. Elleyhill are now advising 56v.