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.Has anybody successfully installed a DALY 16s with CAN to the PC Master software. I get to see COM1 but CAN connection fails!
Have you tried putting a load on it?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
Try a larger load.Yes, after putting load on it, it drops even further to ~7V (that is with small LED strip that consumes ~10W)
What do the individual cells read when the larger load is applied?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:
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.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.
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?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.
If you can connect with BT and the voltage still drops, then I would say the BMS internally has failed.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.
It sounds like it has failed to me as well.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.
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.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:
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.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?