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Common Daly BMS problems?

Just John

Solar Wizard
Joined
Aug 15, 2020
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I'm starting this thread to help people figure out some of the most common Daly BMS problems.
Please feel free to add additional solutions. First I'm going to copy a post I've already made, with some additions.

12v "Smart" BMS:
Daly_USB_Reset.jpg

24v "Smart" BMS lightboard:
Daly_24v_lightboard_connector.jpg

Daly_24v_connector_BMS.jpg


For the 12v model, you can easily make a reset button:

For the 24v model:

Edit to add some additional information others have found:


New Bluetooth dongle with reset switch:


Current Connected has a webpage and video on the topic:


 
After having experienced this and having seen a few similar posts it appears that some DALY BMS show charging current as -ve and discharging current as +ve on the bluetooth ap. Not sure if this is a firmware issue or if there is a fix and whether or not this could cause any issues.
 
Does anyone know the trick to resetting the AH Capacity in some DALY BMS? Half of mine work fine. Some are fine to 50ah then if you set it higher revert to 33.5ah and other odd figures...
 
After having experienced this and having seen a few similar posts it appears that some DALY BMS show charging current as -ve and discharging current as +ve on the bluetooth ap. Not sure if this is a firmware issue or if there is a fix and whether or not this could cause any issues.

That's simply a software setting. Not one you can make, but logically from a software/capacity standpoint, it is indeed a plus current going in, and a negative current going out.
 
A couple of simple changes to your Daly BMS to potentially improve balancing and also partially improve SOC.

Change hidden sinowealth parameter ‘DfilterCur’ to something reasonable like 200mA – it seems to be typically set much higher I have seen 1A,2A and 3 A! Any current ( in or out) less than this will be changed to 0 (including in bluetooth app). This also means any current in and out, less than this, will not be tracked in the SOC. This will also help with balance.

Especially with the this change:

There is a hidden parameter available in sinowealth called ‘Balance open current’ that must be changed to 0 (or even negative) if you want to balance at low or zero current. It was set to 30mA on mine. Changing this to 0 will give you maximum balance time. To give you even more time, change ‘balance open delay’ to zero. This is minor but helps. This is some kind of hold-off before it decides to balance.
 
Just A note about the actual balance currents on the Daly BMS:

I am not sure where to post this but for discussion purpose I’ll put it here.

Summary: The balance current on the Daly BMS Is pulsed with a 20% cycle every second or so. On my 100ADaly it is 30mA pulsed and on my 150A Daly it is 60mA. The net current best case balancing therefore is 6mA on the 100A and 12mA on the 150A?

While I had my Daly BMS all over the floor getting confused measuring currents in and out of balance leads I connected my scope to observe the actual signals. This was done with a 4.7Ohm shunt (I know it’s too large, but it kind of works….). And I observed this: (single cell being balanced):
DalyBalanceCurrent1Cell.jpg
This shows 120mV@4.7Ohm, or about 30mA at a 20% duty cycle.

If you connect 2 balance leads with shunt it looks like this (apologies for the AC coupled signal on top, I do not have a differential probe).
DalyBalanceCurrentMostCells.jpg
This shows that the BMS sequences alternating cells – with the associated current in and out. + or -.


If you read this with a DC ammeter you will get many confusing results due to the averaging/pulsing/sign etc. it depends on the meter! If you go to the off grid garage Daly BMS review, you will actually see the volt meter pulsing when one cell is balancing –and apparently giving ‘0’ reading’ when there should be a reading with 2 sequential cells balancing. This is expected from an averaging meter. It will cause a bunch of head scratching as can be seen in the video.

Note:
 
My daly has started randomly going haywire. The bluetooth dongle.

Until you unplug and replug, it stays like this.
Any tips to get it working?.
 

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My daly has started randomly going haywire. The bluetooth dongle.

Until you unplug and replug, it stays like this.
Any tips to get it working?.
Sorry, I got nothing.
I switched to a JBD myself, Daly has too many quality problems.
 
Ah I just posted a new thread about the Daly. Ill ask here. I have a 24v 8s 200a. Two issues

1. How do you start it? Ive seen a video on shorting pins or something, sounds weird. I have seen above about shorting two pins on the Light board lead. My BMS doesn't seem to have come with a light board lead. What even is a light board? Does the touching the two negatives together thing work to start it up?

The Bluetooth has an on/off switch does that now turn the whole BMS on and off?

2. I have 4 leads including the temp sensor that is already plugged in. The other 4 are:

a. one on the back for the main battery leads
b. Light board port
c. UART port
d. CAN/485 port

What do these do? My BMS didn't come with a manual. Does anyone have a link for it?

It looks like the blue tooth goes into the UART port, is that right?

Thanks for your help.
 
1. How do you start it? Ive seen a video on shorting pins or something, sounds weird. I have seen above about shorting two pins on the Light board lead. My BMS doesn't seem to have come with a light board lead. What even is a light board? Does the touching the two negatives together thing work to start it up?

The Bluetooth has an on/off switch does that now turn the whole BMS on and off?

Certainly the switch on the Bluetooth module is by far the easiest way to wake it up.

A light board is just an LED bar graph showing the state of charge, and with a switch that does the same thing the Bluetooth module switch does now. You must order it separately.

A UART (Universal asynchronous receiver-transmitter) is basically a serial port. There are many converter boxes available for cheap if you know what data levels and communication protocols you need. A USB port is serial, and thus easily converted. The Bluetooth module is also a converter from serial to Bluetooth. 485 is another version of serial protocol, and so is CAN bus.


Daly changes their BMS frequently. You can look in the resources section here, but basically, "Good Luck".



Just as an FYI, Daly has so many quality control problems and so little documentation, that most people (who can afford it) eventually switch to a better BMS. Their "dumb" BMS are decent, but their "smart" BMS are just rolling the dice.
 
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Sadly nobody that I've found yet matches their capacity to simplicity balance. Sure, everyone and their uncle makes a 100a BMS, but what are your options when you need a 200a? Daly or 26 wires for 8 cells that have to be shorted just the right way to work?
 
Sadly nobody that I've found yet matches their capacity to simplicity balance. Sure, everyone and their uncle makes a 100a BMS, but what are your options when you need a 200a? Daly or 26 wires for 8 cells that have to be shorted just the right way to work?
Both JBD and JK make some decent BMS that claim to support 200 amps, so do other brands (JBD and JK are just two I've tested).
Generally speaking, you should REALLY try to stay below 0.5C discharge rate, add more batteries in parallel if necessary.

You can of course also go with a relay or contactor BMS as well.
 
Do you have links by chance? I've completely struck out trying to find an 8s BMS that does 200a that ISN'T a Daly or have 20+ extra wires involved.

JK-B2A8S20P is what I have:


I haven't tried this one, it looks like a "dumb" BMS in that it is programmed with parameters from the factory and has no Bluetooth (JBD has always been very responsive in answering questions in my experience, ask them for a datasheet):

JBD does have some rated for up to 300 amps using a relay/contactor, but they have "extra wires" since they go up to 20 cells.

Only 150 amps:
 
Aaahhh AliExpress. You can get anything there if you're willing to roll the dice and wait 6 months. I was hoping for something a little more local to the USA. :(
 
Aaahhh AliExpress. You can get anything there if you're willing to roll the dice and wait 6 months. I was hoping for something a little more local to the USA. :(
I've good luck so far, usually about 2 weeks.
Always use a credit card. Never had a problem, but I also go with known vendors. JBD you are ordering directly from the manufacturer. Hankzor I have ordered from multiple times, they are just slower in shipping.
 
I just pulled the trigger on a couple of their cheaper models. Too bad there's no low temp or BT on those, unless it's something I need to buy and add on? I couldn't make heads or tails of some of their part numbers.
 
I just pulled the trigger on a couple of their cheaper models. Too bad there's no low temp or BT on those, unless it's something I need to buy and add on? I couldn't make heads or tails of some of their part numbers.
Which did you order? Most come by default with Bluetooth and temperature sensors.

If you ordered the same one I did, the Bluetooth is built in and it comes with two temperature sensors.
 
I actually bought 3...

JK-B2A8S20P-H 8s 200a with heater. It talks about 2 probes but doesn't mention low temp protection although you think it would if it supports heaters.

JBD 4s 120 and the JBD 8s 200 basic models which don't say anything about BT or low temp.
I know that the JK-B2A8S20P-H and JBD 4s 120 come with temperature probes and low temperature protection.

The JBD 8s 200 I assume has neither, since it only claims high temperature protection, and the photos show no external temperature sensor. I have no experience with either JBD model you picked.

They seem to be in the process of switching some JBD models, since the 200 amp smart one I've ordered before is not listed anymore.
They may be having a hard time sourcing parts.

I can tell you I have been very happy with these, I have 8 of the 150 amp versions running:

 
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