How do I reset a Daly 24v firmware BMS?

[Brokeoverland]

First off, I am no expert, I built this system based on reading this site and the Victron manuals 4 years ago so there are definitely mistakes in the design.
That said, I have an issue where I have two 24 volt batteries in parallel. Each battery has a Dally 100 amp 24 V 8S BMS and neither are passing current Charge or discharge. Each of the individual cells in both batteries measure between 3.360 to 3.361.

Total battery voltage of each battery measures 26.87 volts before the BMS and nothing on the load side.

These are older BMS’s that have been running for about 4 years now. Attached picture.

I’ve tried to “wake up” or reset the daily BMS by disconnecting the battery from load and connecting P- to B+ for one minute. Tested P- (not attached to load) and there was 3ish volts but I feel that is residual.

I do have two replacement BMS’s on order. But I have questions for this group.

1. Did I just happen to cook 2 BMS’s at the same time? Since these batteries are in parallel I guess could have cooked one previously and just been running off of one battery.
2. Is there a reset on these (older models with no LEDs) that I’m not aware of?

Bonus points question. If I did cook these BMS’s should I go with a 150amp unit? I have a Victron MultiPlus 24 V | 3000 | 70 amp inverter. Which, according to the documentation pulls 70 amps.

Any pointers or recommendations?
Thanks in advance.

 

[chrisski]

Have you tried to jump start each BMS with a 24 VDC power supply over the battery terminals, not the BMS. I did that to wake up a small Daly 24 volt BMS. This was for over discharge.

 

[Q-Dog]

70 amps refers to how much charging the Multiplus can provide to the batteries, not the total current draw from the batteries.

The 24 volt Multiplus 3000 can surge up to 6000 watts, so at lower battery voltages it can draw close to 300 amps. That's why Victron recommends a 300 amp main fuse for this model. Drawing a 2000 watt load can easily pull 100 amps from your batteries. The Multiplus can sustain a 2400 watt load, so up to a continuous 120 or so amps for as long as the batteries can handle it.

100 amp BMSs are definitely undersized for this inverter. For 2 batteries in parallel each battery should be able to provide at least 150 amps each to the inverter. A 200 amp BMS for each battery would be better, so if one battery shuts down, the other isn't severly overloaded.

 

[Zwy]

First off, I am no expert, I built this system based on reading this site and the Victron manuals 4 years ago so there are definitely mistakes in the design.
That said, I have an issue where I have two 24 volt batteries in parallel. Each battery has a Dally 100 amp 24 V 8S BMS and neither are passing current Charge or discharge. Each of the individual cells in both batteries measure between 3.360 to 3.361.

Total battery voltage of each battery measures 26.87 volts before the BMS and nothing on the load side.

These are older BMS’s that have been running for about 4 years now. Attached picture.

I’ve tried to “wake up” or reset the daily BMS by disconnecting the battery from load and connecting P- to B+ for one minute. Tested P- (not attached to load) and there was 3ish volts but I feel that is residual.

I do have two replacement BMS’s on order. But I have questions for this group.

1. Did I just happen to cook 2 BMS’s at the same time? Since these batteries are in parallel I guess could have cooked one previously and just been running off of one battery.
2. Is there a reset on these (older models with no LEDs) that I’m not aware of?

Bonus points question. If I did cook these BMS’s should I go with a 150amp unit? I have a Victron MultiPlus 24 V | 3000 | 70 amp inverter. Which, according to the documentation pulls 70 amps.

Any pointers or recommendations?
Thanks in advance.

Start here: https://diysolarforum.com/threads/daly-24v-8s-initiation-and-software.18644/ and read thru the thread. These usually have the connection for the light board and you can turn on/off with the correct terminals.