First off, today was my record production for this year so far, first time topping 24 KWHs in 2024, and it went all the way up to 25.9 KWHs. It even hit clipping at 3,900 watts in the iQ7 micros for 45 minutes at solar noon.
Too bad the charging hit early topped up the system way too soon.
The DC system also just sat in float most of the day. It was totally done with Absorb mode by about 1 pm.
It obviously would have produced far more energy if it had a place to send it. I scrolled the cursor to where it went to absorb. The time stamp is just 12:28 as the voltage goes flat line. I never even got to see the power peak as it was still climbing when it had to go into limiting. The battery voltage didn't start falling until 6 pm.
As for the false charge start.....
Most of my very short term AI (Anti Islanding) disconnects were from over frequency (error code 25) on the grid. But they were very short glitches that were not noticeable on anything powered by the grid. It was logging 2 or 3 every month until I updated the firmware. The grid stability ride through certainly improved with the update, and there is not a single AI or any other event in the log since Dec. I just looked at the past Events. I had 5 over frequency events in Oct. 23 but then none in Nov. Then 2 more Dec. 16th and 18th of 23. And then the Dec. 19, 2023 was an under frequency (error code 26).
If I had made a change in my PLC code, I would accept I made an error, but I have not edited the flow of the code in any way in several months. I did change a few of the constant values, but that's it. I never had it accidentally send a bulk in a year, and now it did 2 in just a couple days. Seems very odd. And it is not even tied to the firmware update, as it didn't do it for 2 months after the update.
I can't say for sure if it triggers a charge every time it does an AI disconnect. But it certainly did many of the times. A few times it was already charging when the error occurred, and a couple may have been in the charge block time. I do have it set to block charging during the 4 pm to 9 pm peak rate time.
I have started to write out a new flow chart for some changes I want to make. The PLC serves a small web page I can easily monitor and it lets you change some vales in the web. I want to make it so I can use that to stop or force charging with a click, or reduce charging current, or maybe make the sliders control current limits. Here is the basic default web page with my script running.
I didn't use any of the registers that the page is displaying, so it has no control over my system now, but the yellow text window is the virtual LCD screen that is on their larger PLC's, While there is no screen on it, it save the writes to memory and shows it in the online monitor and this webb app as if it was the 20 character by 4 line LCD screen.
Top line, real time clock and modbus connection status
Second line is battery volts, but does show when I change settings, it will show "Force Bulk" or Charge Current 18%
Third line is labels for the last line
Last line W for watts 61 watts to the AC1 grid output, -788 watts coming out of the battery, and 695 watts to the loads in the backup panel.
It seems the Nano-10 only supports up to Relay 136. I can click on the first 8 and they show turning on and off in the live monitor. The other 8 do nothing. The DM[x] are 16 bit holding registers. I skipped the first 8 because I was not sure what I want to use those for for changing on the fly. You can click on them, type in a value and it does update the register in the PLC. The sliders are cute, but sort of a pain. You slide it with the mouse and set a value, but it does not send it to the PLC until you click enter. And even with the 0-100 rang, it is tough to pick an exact value with the mouse. But it also works in reverse. If I set the DM value, the slider moves to the setting in the PLC.
The web page can be edited or even completely replaced, but it is written in HTML and has to be FTP transferred into the PLC memory. I have not done those things, and reading that section of the manual does not feel logical to me yet. It also has a second web page, but it has an error and when I try to open it, it shows some HTML code, then just keeps scrolling with a repeating character. Most likely a missing end of file code and it is just dumping all of the flash memory in the PLC.
Oh well. The few glitches I have had are still fairly minor. I may set the current limits a little lower as the DC solar is doing a great job topping up the battery now. Then if it goes into charge, it won't be sucking up 2,000 watts. I can also time block when it can even send the force bulk command. Then I will know for sure it can't be coming from the PLC at that time of day.
