Chargery BMS 16 strange issues

[toothy]

Last winter I bought a set of Calb CA400's and did the bottom balance procedure and Chargery set up in the shop. All went well including the low cut of contactor set up and the current calibration. I installed the bank on July 3 and the next morning the bank is at 43v! Yes I forgot to set low V disconnect on the inverter, fixed now. Now the Chargery is acting weird it should have disconnected during that event but did not and no settings were changed since last winter when it all worked. Looked at the settings menu yesterday and my current calibration had changed from a set -13 to -32 on its own, I reset it to -13 and a few hours later its at -18? My SOC screen that used to seem to work now shows 0% and the back light never goes off. I unplugged the display and changed the display timer all with no change.

Anybody seen such behavior? Or is it bricked, it seems to still be balancing.

Thanks
Wade

 

[grizzzman]

Did you do the three separate steps involved in setting up a shunt?

 

[toothy]

Yes, the shunt was set up carefully and functioned properly last winter. The curiosity is why the values would change without any input on the setting screen, more than once... Then there is the back light and 0% SOC that worked a few days ago.

 

[Bob B]

Did you do the update?

 

[grizzzman]

Yes, the shunt was set up carefully and functioned properly last winter. The curiosity is why the values would change without any input on the setting screen, more than once... Then there is the back light and 0% SOC that worked a few days ago.

What Relay/Contactors are you using?

 

[toothy]

I have not updated the firmware, port stuff usually causes me trouble!

The contactors are Tyco TE Kilovac EV200AAANA.

 

[grizzzman]

I'm running a BMS8T and the same contactors when I tried to run two, the BMS would reboot causing programming issues at times. When I tested Voltage at the output with a graphing meter I found that it was dropping to two volts. I now use the output to trigger mini micro relays to trigger the contactors instead of directly. Perhaps you are dealing with a similar issue?

 

[toothy]

The contractors are holding fine but maybe the load is freaking out the BMS. Adding the high V contractor has been the only real change since testing in the winter. I may just do away with the high V contractor and see if it gets happier, or both!

Thanks for the thoughts
w

 

[toothy]

So... I removed the high V contactor and cycled the BMS and now all is back to normal. One curious thing the BMS main box was warm to the touch before, 85+/- degrees now it is back to being cool to the touch and the balance differential has gone down quite a bit, from 35mv +/- to 10+/-. I guess the contactors were just working it more than it could handle.

Thanks
W

 

[grizzzman]

So... I removed the high V contactor and cycled the BMS and now all is back to normal. One curious thing the BMS main box was warm to the touch before, 85+/- degrees now it is back to being cool to the touch and the balance differential has gone down quite a bit, from 35mv +/- to 10+/-. I guess the contactors were just working it more than it could handle.

Thanks
W

I'm glad you got it figured out!

 

[Craig]

So... I removed the high V contactor and cycled the BMS and now all is back to normal. One curious thing the BMS main box was warm to the touch before, 85+/- degrees now it is back to being cool to the touch and the balance differential has gone down quite a bit, from 35mv +/- to 10+/-. I guess the contactors were just working it more than it could handle.

Thanks
W

You probably have balance set to balance above 20mv delta so at 10mV it does not balance and at 35mV it does that is what makes the box hot.

 

[toothy]

That's a plausible explanation but... It has been balancing with a setting of 20mv since the 3rd of July with no real change, then 2 hours after I disconnected the contactor and power cycled the BMS it is cool to the touch and the balance is way different. It didn't balance those 400Ah cells in that time frame, something else changed and the screen started following its programmed sleep timer setting. It just seems like the removal of the one contactor changed something, but it could have been the power cycle of the BMS. Thanks for the input, I'm just glad it's working!

 

[toothy]

Well it's misbehaving again. I was showing the house yesterday and heard the Chargery beeper go off a few beeps like 5 seconds, it was about the time it went from bulk/absorb to float, it did not trip the LVD contactor and I have removed the HVD contactor. When I went to look at it about 10 minutes later the displayed SOC was at 0% the screen that shows which cell kicked the alarm was all 0's. The display stayed on until I did a reboot today. Do I have some setting out of wack? It was not near my upper or lower voltage alarm setting battery V at the time 54.7. Having the alarm going off is not the greatest sales inducement.

 

[grizzzman]

What risk is there to updating the firmware to see if this will correct this issue?

 

[Craig]

I wish I had an answer but i'm stumped. I will e-mail Jason Wang about this thread.

 

[Steve_S]

Toothy, you said you were using two TE/Kilovac EVE200 relays, then cut back to one and that seemed to have worked for a bit.

This may be a stupid question but are you sure both relay coils are 12V ? they do come in different coil voltages.
If the small energy-saver board on the relay went bad for some reason, it could have caused damage but not likely.
One way to determine the trigger point for the coil, is to use a regulated 12V power supply that can control the amps / milliamps.
Nothing jumps out in your settings, not seen mentioned, you do have balancing OFF on Charge, Discharge & Storage, right ?, as that burns power off the high cell(s).

 

[toothy]

Steve_S the contactors were both 12 V and both have been removed. I have it set to balance "ON" in every stage.

It dropped the LVD contactor out for no good reason the other day, so I updated the firmware and reset to factory defaults. If it had done that on a sunny day the 3 Classics might not have been happy, it reconnected in about 2 seconds. Now the SOC is always 0%, it does not correct with a reboot and the new internal resistance screen shows all 0's. The screen is now always lit up with time set for 5 minutes. When I did the factory reset it said the bank was 4000Ah, I wish!

So do I buy another one of the same things that didn't work out so well or go some other direction? I wish they sold just the main unit. My ROI on this one was pretty poor, but it does seem to be balancing so that's something!

 

[Cal]

I notice in your setup the Overcharge P voltage is greater than Cell Full Voltage. I believe it should be the other way around. That probably doesn’t make any difference in your situation.

You should check out ElectroDacus BMS. That’s the route I would take.

 

[Steve_S]

Steve_S the contactors were both 12 V and both have been removed. I have it set to balance "ON" in every stage.

It dropped the LVD contactor out for no good reason the other day, so I updated the firmware and reset to factory defaults. If it had done that on a sunny day the 3 Classics might not have been happy, it reconnected in about 2 seconds. Now the SOC is always 0%, it does not correct with a reboot and the new internal resistance screen shows all 0's. The screen is now always lit up with time set for 5 minutes. When I did the factory reset it said the bank was 4000Ah, I wish!

So do I buy another one of the same things that didn't work out so well or go some other direction? I wish they sold just the main unit. My ROI on this one was pretty poor, but it does seem to be balancing so that's something!

I have no idea why it would do that, Craig might have an idea, if that fails, e-mailing Jason can't hurt.

 

[toothy]

Thanks guys, I changed the suggested full and p voltage no change.

 

[Tony]

Not exactly the same symptoms you are experiencing... In addition to the problems with the BMS16T cell mV reported values vs DMM reported values I posted on another thread, I have been dealing with two other problems: 1) high temperature on the main unit and 2) BMS SOC and AHs catastrophic drop to 0.

I noticed some time ago how hot the main unit was running. I measured the cells/posts and the BMS main unit case. I was seeing a 20 degree celsius higher measurement at the main unit case. This came up as an issue because, my BMS is no longer balancing - at least the balance indicators included in the 4.0 firmware no longer is displayed when they should be. Jason has been saying the BMS is over temperature internally, which has a cutoff at 55c at the PCB heatsink. After much back and forth, Jason, asked me to open the case and I found the internal temperature was 55c as he was saying. In fact, without balance running, the contactors' connectors disconnected and no charge or discharge I have a 30c difference between the surrounding air temperature and the internal PCB temperature. The measurements this morning with the temperature in the garage at 25c the internal PCB was 55c. That is the over temperature point for the BMS. He said it will start balancing again when the temperature drops below 50c. So, that is when it is moderate temperature outside! I'm waiting to hear back from Jason, but he has not been alarmed at how hot the BMS is running. Instead he keeps saying I need to install a heatsink or fin to the case of the main unit.

I thought the next issue was because I had not properly calibrated the shunt or I hadn't properly charged the battery, so I didn't over react to the first two times it occurred. I took a couple of short trips with the golf cart and it stopped in the middle of the road twice during different trips. I checked the display - SOC and AHs were 0. I don't recall what WHs or battery voltage was as I thought the battery was drained and so we towed the cart home. Jason suggested I calibrate the shunt. After doing that it happened again. SOC and AHs at 0 and this time I noticed the WHs was ~7,300. I had been monitoring the display and just a minute before the catastrophic drop to 0, the SOC showed about 53% and I think AHs was around 123AHs. This time I turned off the BMS and then turned it on again. SOC jumped back up, but AH was still 0. The cart ran fine on the trip back home. After getting home, the cells showed 3.30v to 3.36v and the battery showed 53.34v. Not a drained battery after-all!

I upgraded the BMS16T to 4.0 before I installed it, so I do not have any observations about 4.0 firmware vs the earlier 3.x firmware regarding any of the issues I have experienced.

I am getting to the point of seeking another solution. Driving the cart on the community streets with cars around is scary when the cart just stops. I could wind up being hit from behind. I guess I will start looking at the Electrodacus as I need 150A continuous discharge and my battery charger could be damaged (per the manufacturer) if I disrupt the charge current while it is operating. They have an enable switch/jumper that is supposed to be used. For that I need a relay to control it.

 

[Tony]

Not exactly the same symptoms you are experiencing... In addition to the problems with the BMS16T cell mV reported values vs DMM reported values I posted on another thread, I have been dealing with two other problems: 1) high temperature on the main unit and 2) BMS SOC and AHs catastrophic drop to 0.

I noticed some time ago how hot the main unit was running. I measured the cells/posts and the BMS main unit case. I was seeing a 20 degree celsius higher measurement at the main unit case. This came up as an issue because, my BMS is no longer balancing - at least the balance indicators included in the 4.0 firmware no longer is displayed when they should be. Jason has been saying the BMS is over temperature internally, which has a cutoff at 55c at the PCB heatsink. After much back and forth, Jason, asked me to open the case and I found the internal temperature was 55c as he was saying. In fact, without balance running, the contactors' connectors disconnected and no charge or discharge I have a 30c difference between the surrounding air temperature and the internal PCB temperature. The measurements this morning with the temperature in the garage at 25c the internal PCB was 55c. That is the over temperature point for the BMS. He said it will start balancing again when the temperature drops below 50c. So, that is when it is moderate temperature outside! I'm waiting to hear back from Jason, but he has not been alarmed at how hot the BMS is running. Instead he keeps saying I need to install a heatsink or fin to the case of the main unit.

I thought the next issue was because I had not properly calibrated the shunt or I hadn't properly charged the battery, so I didn't over react to the first two times it occurred. I took a couple of short trips with the golf cart and it stopped in the middle of the road twice during different trips. I checked the display - SOC and AHs were 0. I don't recall what WHs or battery voltage was as I thought the battery was drained and so we towed the cart home. Jason suggested I calibrate the shunt. After doing that it happened again. SOC and AHs at 0 and this time I noticed the WHs was ~7,300. I had been monitoring the display and just a minute before the catastrophic drop to 0, the SOC showed about 53% and I think AHs was around 123AHs. This time I turned off the BMS and then turned it on again. SOC jumped back up, but AH was still 0. The cart ran fine on the trip back home. After getting home, the cells showed 3.30v to 3.36v and the battery showed 53.34v. Not a drained battery after-all!

I upgraded the BMS16T to 4.0 before I installed it, so I do not have any observations about 4.0 firmware vs the earlier 3.x firmware regarding any of the issues I have experienced.

I am getting to the point of seeking another solution. Driving the cart on the community streets with cars around is scary when the cart just stops. I could wind up being hit from behind. I guess I will start looking at the Electrodacus as I need 150A continuous discharge and my battery charger could be damaged (per the manufacturer) if I disrupt the charge current while it is operating. They have an enable switch/jumper that is supposed to be used. For that I need a relay to control it.

An update from Jason on the temperature issue. He says he wants me to put a fan in the PCB heatsink that is inside the case (see attachment.) Wow, that is the solution? Anyone else having temperature issues with the BMS16T?

 

[Tony]

Ok. I removed the case and turned balancing back on. Balancing did run for a short time and then stopped. I checked the temperature and sure enough, the PCB board was reading 55c. I put a fan near the board and the temperature dropped to 44c - balancing restarted. It could be the high temperature affected the catastrophic drop of SOC and AH to 0 as well, but it has not affected the cell V value vs the DMM V value.

So, from what I have been reading on the forum, no one else has experienced this heat problem. Am I right?

 

[toothy]

The 0% SOC I now have since the update is always 0. Before the update it went away after a reboot. My temp problem went away after removing the high contactor but wasn’t nearly as bad as you describe. I’m in Alaska 60 deg for high ambient, so that probably makes some difference.

 

[Cal]

@Tony you mention battery charger might be damaged if disconnected? I presume you mean disconnecting the charging current. There are other methods of disabling the charger. What type charger do you have? I have an Iota/IQ4 converter which I’ve modified to accept the disconnect signal from Chargery BMS. A relay just switches a small current to reduce charging voltage to a safe level. There are other methods like inserting a disconnect relay at the AC input.

I’ve also had the experience where the Chargery suddenly shows zero SOC. SOC meter displays almost always greater the 90% during my current 8 week camping trip. But suddenly yesterday buzzer started beeping due to low voltage and displaying 0% SOC. The problem I believe is that Chargery current resolution is poor. The AH counter is not accurate due to the dismal current resolution. The BMS reads my motor home quiescent current of 0.7A as zero. Over time the counter gets way out of wack. The SOC meter is useless unless the battery can be fully charged which I presume resets the counter.