question

@Nicok3 The first thing to do would be to update the mppt firmware as suggested by Victron Connect.

Battery voltage is not the original issue Why not?? The plot clearly shows battery voltage as low as 16v. Low enough for a Li battery BMS to disconnect.

Perhaps you could share some meaningful information about your system. Eg battery, loads, PV voltages, mppt detailed history, mppt charge settings......

In case I am crashing the party please disregard my post. I just wanted to add that I have exactly the same problem with a 75/15 working in tandem with a (flawless) 100/20. FW 1.63 on both, I will update as recommended and see how the 75/15 behaves.

The graph shows you the voltages at which my 75/15 froze overnight, the device list displays the previous day's yield. The screenshot of the device list is taken a couple of minutes after powering on the 75/15 (after being powered off for a couple of hours - minutes are not sufficient). The starting battery voltage displayed was 28,40 V, slowly falling towards the value displayed by the other devices. (Graph and screenshot are from separate occurances, it is a recurring problem.)

This posting is supposed to add data in the hope of helping to solve nikog3's problem. I do not expect active support for my problem within this thread.

Greetings, I am having the EXACT same problem with two 75/10s in the same system (two different sites). I have both logs and graphs from both sites. The graphs show exactly the same symptoms as the other two folks reporting this problem. I'm not sure the symptoms on my sites are different enough from what has already been reported in this thread, however I'll be happy to share the details if it would be useful to the community. It may be worth noting that both of these 75/10 units are installed directly adjacent to Schneider TRIO JR900 radios in the cabinet. It may also be important to know that the log file and the graph tell different stories. I have attached both here.

SolarHistory.xlsx

We have plenty of 75/10, 75/15, 100/20, 100/50, and 150/35 units in the field and these are the only ones we have seen with this problem, one of them has done it twice.

This is a critical issue for us because when these die we lose an important repeater and gateway site in a radio network and have to drive 9 hours round trip with an ATV in tow for the last mile to deal with it. One site has done it once and the other has done it twice. We always do the firmware updates if there are any pending. There are too many instances of this problem for this to be a client system design or installation problem. Please escalate this to Victron's engineering group. We love Victron products, but this is a fatal problem and one that will cause us to stop using the products until the issue is both acknowledged and addressed.

Thank you to all of us for coming with details about your problems. I really hope that Victron will be able to resolve it quickly, as most of the site on which these devices are installed are hard (impossible) to reach ...

Hi @Nicok3

Firmware version 1.64 has been released for these MPPTs which might solve this issue (see also https://professional.victronenergy.com/news/detail/244/). This version is included in the latest VictronConnect. Have you perhaps already updated the firmware and if so, can you say whether this helps in the reported issue?

Kind regards,

Thiemo van Engelen

Hi @Thiemo van Engelen (Victron Energy staff)

I'll do the update on all MPPT to which I have access, I'll let you know if the problem happens again or not.

Regards,

Nicolas

I just updated three 75/10s on Friday in this system to 1.64. One of them, the most problematic one, had locked up again prior to my arrival. The other two were running properly. I'll report back.