diy solar

diy solar

More DALY smart BMS issues

Has anybody successfully installed a DALY 16s with CAN to the PC Master software. I get to see COM1 but CAN connection fails!
 
Has anybody successfully installed a DALY 16s with CAN to the PC Master software. I get to see COM1 but CAN connection fails!
I feel your pain. I have an 8S 24VDC Smart BMS with Can, 485 and Bluetooth. The CAN and Bluetooth both use the UART port. But only the Bluetooth works on it.
The 485 worked for about 3 weeks then stopped working. I'm still going back and forth with their tech support on this.
I wish there was a way to test this using telnet or something in order to confirm the port on the BMS is actually responding.
 
@aldogrech I ordered and received a Daly 16S 300A from the Aliexpress' Daly official store. I'm still waiting on my batteries to show up so I hooked up 16 LifePo4 26650P to test. I have the power display board, the Bluetooth module and the RS485 to USB converter.
I've been able to play around with the Smart BMS app and the PC BmsMonitor program.
Some of the download resources from Daly are located here.
I'm not sure it that'll help you ord not.
 
Hi everyone,

I have similar troubles:
I've build 4s battery from 280ah EVE cells and wired it up with DALY 60A smart BMS. At this point the BMS is off - Battery + to BMS's P- is close to 0V. After applying some charge voltage, the BMS wakes up and charges battery. At this point I can also connect to it using Bluetooth - no problem.

However when I disconnect charger, the voltage Battery + to BMS's P- drops to 10.8V. I tried shorting the 2 pints next to "Monitor" but does not seem to have any effect. I also tried shortly connecting BMS's B- and P- cables, also no effect. I've checked that voltage between all neighboring balance leads is ~3.3V

I found that when I go to the the last page in parameter settings and switch "Dischg switch" to off, the voltage drops close to 0V and when I turn it on again, the voltage briefly goes to ~13.0V, within couple seconds decays to ~12V and then drops back to 10.8V and stays there.

Any help MUCH appreciated! Thanks!
ps: I'm attaching printscreens from all pages in the app in case I overlooked something
 

Attachments

  • Screenshot_20210628-123909_SMART BMS.jpg
    Screenshot_20210628-123909_SMART BMS.jpg
    133.8 KB · Views: 19
  • Screenshot_20210628-123903_SMART BMS.jpg
    Screenshot_20210628-123903_SMART BMS.jpg
    131.4 KB · Views: 18
  • Screenshot_20210628-123859_SMART BMS.jpg
    Screenshot_20210628-123859_SMART BMS.jpg
    138.9 KB · Views: 18
  • Screenshot_20210628-123855_SMART BMS.jpg
    Screenshot_20210628-123855_SMART BMS.jpg
    143 KB · Views: 18
  • Screenshot_20210628-123832_SMART BMS.jpg
    Screenshot_20210628-123832_SMART BMS.jpg
    112.2 KB · Views: 19
  • Screenshot_20210628-123824_SMART BMS.jpg
    Screenshot_20210628-123824_SMART BMS.jpg
    139.5 KB · Views: 20
  • Screenshot_20210628-123817_SMART BMS.jpg
    Screenshot_20210628-123817_SMART BMS.jpg
    151.6 KB · Views: 20
Last edited:
Hi everyone,

I have similar troubles:
I've build 4s battery from 280ah EVE cells and wired it up with DALY 50A smart BMS. At this point the BMS is off - Battery + to BMS's P- is close to 0V. After applying some charge voltage, the BMS wakes up and charges battery. At this point I can also connect to it using Bluetooth - no problem.

However when I disconnect charger, the voltage Battery + to BMS's P- drops to 10.8V. I tried shorting the 2 pints next to "Monitor" but does not seem to have any effect. I also tried shortly connecting BMS's B- and P- cables, also no effect. I've checked that voltage between all neighboring balance leads is ~3.3V

I found that when I go to the the last page in parameter settings and switch "Dischg switch" to off, the voltage drops close to 0V and when I turn it on again, the voltage briefly goes to ~13.0V, within couple seconds decays to ~12V and then drops back to 10.8V and stays there.

Any help MUCH appreciated! Thanks!
ps: I'm attaching printscreens from all pages in the app in case I overlooked something
Have you tried putting a load on it?
 
Yes, after putting load on it, it drops even further to ~7V (that is with small LED strip that consumes ~10W)
 
Hmm, but how do I load it if the voltage just drops? Invertor won't run on 7V (and I suspect that it didn't drop further just because the LEDs stop drawing any current at that voltage.)

Also do I understand it correctly that if I'm able to connect to BMS via bluetooth, it is already waken up? To me feels like the BMS is actually cutting off discharge for some reason I didn't find yet... After switching off and on the "discharge switch" in app, it briefly gives me the 13.4V, but then it re-evaluates something and shuts the discharge off.. At least that is the feeling I get.

I'm also attaching picture showing which 2 pins I tried shorting - just in case I didn't guess the correct 2 pins:
 

Attachments

  • 20210628_120639.jpg
    20210628_120639.jpg
    175.9 KB · Views: 29
Hmm, but how do I load it if the voltage just drops? Invertor won't run on 7V (and I suspect that it didn't drop further just because the LEDs stop drawing any current at that voltage.)

Also do I understand it correctly that if I'm able to connect to BMS via bluetooth, it is already waken up? To me feels like the BMS is actually cutting off discharge for some reason I didn't find yet... After switching off and on the "discharge switch" in app, it briefly gives me the 13.4V, but then it re-evaluates something and shuts the discharge off.. At least that is the feeling I get.

I'm also attaching picture showing which 2 pins I tried shorting - just in case I didn't guess the correct 2 pins:
What do the individual cells read when the larger load is applied?
 
Should I apply larger load directly on the battery (bypassing the BMS)? I'm unable to apply load through the BMS since the voltage just drops way down.
 
Should I apply larger load directly on the battery (bypassing the BMS)? I'm unable to apply load through the BMS since the voltage just drops way down.
Thru the BMS if possible, you are looking for low cell voltage. If the BMS shuts down, then you have to check each cell with the voltmeter under load.

Are you certain you don't have a cell connection that doesn't have excessive resistance and balance leads also have a good connection? The BMS is looking for 2 things under load, individual cell voltage that hits the low voltage cutoff setting and the other is full pack voltage. Either one can cause a cutoff.
 
Thru the BMS if possible, you are looking for low cell voltage. If the BMS shuts down, then you have to check each cell with the voltmeter under load.

Are you certain you don't have a cell connection that doesn't have excessive resistance and balance leads also have a good connection? The BMS is looking for 2 things under load, individual cell voltage that hits the low voltage cutoff setting and the other is full pack voltage. Either one can cause a cutoff.
Well, the thing is that the voltage is cut off even without load. Through the BMS I get only 10.8V with no load, whenever load is applied, the voltage drops to a value when the load shuts down. During the whole thing, the individual cells measure 3.34V (both using multimeter and in the app). And since app is showing correct voltages for each cell, it seems that the balance leads also shouldn't be the culprit right?

Also, I tried applying load directly to the battery + and - and it works fine, no cell drops in voltage.
 
Well, the thing is that the voltage is cut off even without load. Through the BMS I get only 10.8V with no load, whenever load is applied, the voltage drops to a value when the load shuts down. During the whole thing, the individual cells measure 3.34V (both using multimeter and in the app). And since app is showing correct voltages for each cell, it seems that the balance leads also shouldn't be the culprit right?

Also, I tried applying load directly to the battery + and - and it works fine, no cell drops in voltage.
If you can connect with BT and the voltage still drops, then I would say the BMS internally has failed.

I prefer a derate of 50% on any Chinese BMS, with a 60a Daly, I would limit load to 30a.
 
If you can connect with BT and the voltage still drops, then I would say the BMS internally has failed.

I prefer a derate of 50% on any Chinese BMS, with a 60a Daly, I would limit load to 30a.
It sounds like it has failed to me as well.
 
Hmm, but how do I load it if the voltage just drops? Invertor won't run on 7V (and I suspect that it didn't drop further just because the LEDs stop drawing any current at that voltage.)

Also do I understand it correctly that if I'm able to connect to BMS via bluetooth, it is already waken up? To me feels like the BMS is actually cutting off discharge for some reason I didn't find yet... After switching off and on the "discharge switch" in app, it briefly gives me the 13.4V, but then it re-evaluates something and shuts the discharge off.. At least that is the feeling I get.

I'm also attaching picture showing which 2 pins I tried shorting - just in case I didn't guess the correct 2 pins:
Daly likes to change things at random, especially on their 4 cell models. Your guess is as good as mine about where (or even if) the key pins are now.
 
Ok, one last question: does anyone know about a shop/source where I could buy a BMS and have it delivered to Europe (Slovakia) within 2 weeks? This one came from China and it took ~1.5 months. Thanks.
 
Hey, one more sinister idea: if I can't get my hands on another BMS before I leave for vacation, can I just do following?
Connect BMS but use it only for charging and connect load directly to battery +. I would regularly (daily) check the battery voltage and manually disconnect if voltage gets close to 12V (or any cell drops below 3V). Additionally the solar charge controller will have setting to stop charging at given voltage.

My use case: I intent to run only small loads - small 12v fridge, some LED lights and charge laptop/phones from it. I don't expect to ever draw more than 15A. For this purpose I have over-sized system with 280ah battery.

Am I crazy for thinking about doing it this way?
 
Hey, one more sinister idea: if I can't get my hands on another BMS before I leave for vacation, can I just do following?
Connect BMS but use it only for charging and connect load directly to battery +. I would regularly (daily) check the battery voltage and manually disconnect if voltage gets close to 12V (or any cell drops below 3V). Additionally the solar charge controller will have setting to stop charging at given voltage.

My use case: I intent to run only small loads - small 12v fridge, some LED lights and charge laptop/phones from it. I don't expect to ever draw more than 15A. For this purpose I have over-sized system with 280ah battery.

Am I crazy for thinking about doing it this way?
you could but thats a lot of monitoring to avoid damage. the best thing is to get the battery monitor dongle with the on/off switch. its like 10 bucks on amazon and it fixed all the issues I had with my DALY.
 
Update on my 16s DALY BMS. after useing the BMS and batteries for about 3 weeks? I killed the BMS.

so I went to finish my battery packs this weekend at the cabin. Meaning that I wanted to rearrange the B-, and P- cables so that I could move the BMS to a "safer" location while still having the temp sensor reach the battery pack, as well as clean up the rest of the wiring for neatness.

Here is the following sequence I used to unhook the DALY. I shut off solar charging at the SCC. so zero amps coming in. shut off the inverter, so zero amps going out. unhooked the connector for the balance leads, I then unhooked the P- wire and last the B- wire. (did not unplug the temp sensor, or the Bluetooth dongle nor the light board. )

I then moved the BMS to where its permanent home would be and then reversed the procedure. hooked up the B- and then the P- and plugged in the lead connector and pushed the light board button to turn it on. the Bluetooth loaded, showed a bunch of error codes and would not respond after that. tried unit reset, no go, tried factory reset, no go. below are is the codes it tossed. i think its toast.

looked at it all and decided it must have been inrush current that damaged it. broke out spare BMS. doubled checked all wiring, opened inverter disconnect this time (duhh?) and plugged in the BMS. it works! double checked all functions, reset all parameters and then went to hook up the solar controller. it has a bit of inrush, so I used a jumper cable direct from the batter to bypass the BMS to avoid inrush on it. Hooked up the jumper, solar controller came on, flipped breaker and removed the bypass jump cable. double checked all functions, no problems, then flipped the breaker to the panels. stated charging, once again no issues. GTG. moved on to the inverter it has a really big inrush so I once again used a jumper cable to the batter bypassing the BMS to preload it then flipped its disconnect to the on and removed the jumper. this time got the exact same codes out of the bms toasted number two!... now I am awaiting the resistors i ordered form amazon last week so that I can try it one last time with my last spare BMS..

the biggest issue i see is that if inrush can damage it, what happens when the BMS disconnects the output or input and then reconnects? it seems to me that it would have inrush then as well and do the same thing. and better yet why didn't it give me these fits the first time?
 

Attachments

  • bms2.png
    bms2.png
    201.2 KB · Views: 18
  • bms1.png
    bms1.png
    199.8 KB · Views: 18
Back
Top