Just now, The Terrible Triplett said:

Maybe I must do that late afternoons to not discharge the batts for better after 12 evening use ... will see.

Yup, I do that too. Between 6PM and midnight, I don't discharge, for one simple reason: If there is a late-night outage, something that has been known to happen, I don't want to sit with empty batteries. I don't have a TOU tariff and there is no benefit for me to shave my peak usage... so I just don't 🙂

 

Hi everyone,

I though I should revive this thread instead of a new one since there is lots of information already shared;

I installed two new US3000 Pylontech batteries yesterday connected to a Victron ESS system that is working 100% albeit with lead acid batteries before I swapped them for the Pylons.

After the install the Venus GX detected both batteries with a combined SoC of 64%. The one brick however had a lower SoC (based on the LEDs) at ~60% and the the other ~75%. So there was an imbalance between the two bricks.

During the charge cycle today the batteries reached 91% SoC and then I got the Pylontech battery warning and high alarm at 52.2 V. The Charge Current Limit (CCL) was also reduced to 0A initially.

OK, I have read all the comments and suggestions in the thread and would like to think that the batteries are busy balancing between the 2 bricks. I have noticed that the SoC has slowly increased to 94% during the course of the day. The one brick is at 100% SoC (looking at the LEDs) and the other at 85% (5 LEDs on the SoC). So there is still an imbalance between the two. I have also noticed that the one battery, all 6 SoC LEDS go off (run LED still flashing) and then come back on again. This happens on both batteries from time to time. Has anybody seen this behavior from the batteries? I'm guessing it is part of the balancing process? I could not find any reference to this LED sequence.

The Venus and Multi is configured as suggested by Victron's documenation. Multi on FW 467 and Venus on 2.40

I was wondering if I should try to increase the charge voltage to 53V; updated the Multi in VE.Config but the charge voltage remains at 52V. 

Plonkster suggested this method to force the charging to 53V in case the balances are "lazy" but I'm not sure how the patch works:

On 2019/08/01 at 8:42 AM, plonkster said:

 

So why did we develop an imbalance? Maybe (at 52V) the balancers might not be as effective as they are higher up. Now I was told by the manufacturer (or at least someone that works there) that 51.8V is high enough to start balancing, and there are certainly many here who run with 52V without any problems. So this was a shot in the dark, a wild guess, and so the plan was simply to push the voltage up and see what happens (either the problem gets worse, or it goes away). What I did, because @Jaco de Jongh asked me, is patch the 52V limit up to 53V. The idea is to let it run like that for a few days (I assume you cycle the batteries?) and see if the problem (or others) returns

I'm sure this issue will resolve over time, just want to check if there is new wisdom out there on this high voltage issue.

I will try to build a console cable to check on the actual state of the two bricks as well as the individual cells when I have some spare time.

Thanks for reading

Hendrik

2 hours ago, stabilo said:

I have also noticed that the one battery, all 6 SoC LEDS go off (run LED still flashing) and then come back on again. This happens on both batteries from time to time. Has anybody seen this behavior from the batteries? I'm guessing it is part of the balancing process? I could not find any reference to this LED sequence.

This is normal behavior. Details here:

• When a brick is discharging a steady led bar indicates the actual SOC.
• When a brick is being charged, the led bar indicated actual SOC, plus the last led in the bar is slowly blinking to indicate that the charging is in process.
• When a brick is ON, but there's no energy flow (no charging, no discharging) then the led bar is dark.

So, the dark led bar, that you see, means that the batteries are idle. In reality they are not really idle, but the current flow is so small, that the internal BMS can't measure it. From time to time, the BMS notices the current and shows the ledbar for a second. That's normal too.

 

2 hours ago, stabilo said:

I will try to build a console cable to check on the actual state of the two bricks as well as the individual cells when I have some spare time.

Good idea.
I would say that your bricks are really a bit unbalanced and that's the reason why the cells in the fully charged one are experiencing overvoltage. Just check it with the software. Also, check if there is a measurable balancing current between the bricks. If not, the quickest approach may be to disconnect the bricks, charge 1st to 100%, then charge 2nd do 100% and after that just connect the bricks together and carry on.

@Youda thanks for the information! 

It was a bit overcast today so the Pylons only charged to around 87% (from 50%) combined SoC as reported by the Venus. Around 1800 both bricks had 5 LEDS on so it looks as if some balancing took place during the night or during the charge cycle. 

I decided to make up a console cable and used battery view to query the 2 bricks:

Battery Module1 SoC = 85% and Module2 SoC = 88%. I think if I leave them to balance all should be OK by the weekend. Also hoping for some proper solar charging tomorrow to get them to 100% SoC.

I noticed that the terminal window can be used as a CLI (as you have indicated). How can I get  a list of usable commands?

 

   

The Pylontec bms manages the soc (which equals about 16% per light) on the battery. 

I only have a look at these and have been living happily with them for two years now.

The lights of the four of them (usb2000) are always in sync (more or less) unless they are charging from empty after load shedding.

One battery had a red alarm light last week (picked it up by chance as they are behind a heavy steel door). I switched it off and on it and it's back to normal. No idea why it did it as I don't "watchdog" them.

 

On 2020/02/10 at 7:03 PM, stabilo said:

I noticed that the terminal window can be used as a CLI (as you have indicated). How can I get  a list of usable commands?

HELP

On 2019/08/01 at 9:38 AM, Kilowatt said:

Thank you plonkster, 

Unfortunately today is raining and overcast, not sure if we will get to full charge or not.

I do cycle my batteries, and also run them them on the optimized without battery life setting. There are also times when the battery has a large discharge current then immediately followed by a large charge current, so i am not sure if this confuses it or not. 

I won't make any changes to the firmware, so we can let it run as set and hopefully no more alarms. I will give you feedback, hopefully it will just be to confirm all is in order. 

thanks for all the help👍

So i thought i would give some feed back on this matter, i should have done it a while back already. I have made no changes to my system since Plonkster did the Patch. I still get the odd over current alarm, but not often, probably happens once every month or second month now. I don't worry about it anymore. I am happy, i like my Victron setup and it continues to work well. 

56 minutes ago, Kilowatt said:

I have made no changes to my system since Plonkster did the Patch

The slight voltage increase was rolled into Venus 2.60, so in a future release it will be standard.