DALY Smart BMS 4S 250A issue: incorect voltage on P-

[walter-]

Risking that I ask something asked before...
DALY Smart BMS 4S 250A...
I build the 4S battery: without BMS it works fine against the 2.000W inverter.
No I connect the Daly BMS.
I followed the instructions in this manual: this manual
So the simple steps: I connect BMS B- to the batteries Minus; connected the sensing cable (black on battery Minus, first red cable etc...): I measured on the connector of the sensing cable and got nicely 3.3V, 6,6V, 9.9 and 13,17V (except for the last one, the other are rounded, cells are perfectly balanced).
then I connected sensing cable (actually correct word?) and I expected 13,7V on the P- of the BMS.
But I got something like 9,62V.
I had ordered 3 same BMSes: checked on number 2: same issue (with the same wire).

What is going wrong here?
What is the most likely issue here?

I am trying to contact Daly as well.

Walter

 

[Diysolar123]

well, its the smart BMS so did you connect your computer or phone to the BMS and see what is going on?
That would be a quick first step.

 

[walter-]

The manual says to start over o
if you don't have 12V on the P-; so I gues I have to be smarter then the manual....

 

[Uoavitar]

Sounds like your not waking up the BMS.

Check out this thread

https://diysolarforum.com/threads/more-daly-smart-bms-issues.19751/page-2#post-245158

 

[walter-]

Is the waking up not about activating bluetooth?

 

[walter-]

So I did; small screwdriver to the 2 pins and up; I starts working....

Who's bad design is that? And why is that not in the manual!!

Thanks a lot for the input!

Walter

 

[walter-]

Feedback from Seller - Daly official store : I should have connected a 'Charger' to the BMS. But I believe I did....
I got another manual: https://us-icbuim-file.oss-us-east-...t Cells voltage before wiring - Smart BMS.pdf

This one states to use the SOC indicator/ button to activate the BMS; But Daly says they don't have the SOC indicator for a 4S.

 

[walter-]

Another update: seller says they will build a bluetooth module with an activation button... (so they know the issue ;-)).

 

[Zwy]

So I did; small screwdriver to the 2 pins and up; I starts working....

Who's bad design is that? And why is that not in the manual!!

Thanks a lot for the input!

Walter

If you had purchased the light board, you would have had the switch needed for the 2 pins. Nothing wrong with the design, it's just that the documentation doesn't mention this. Many of us here figured it out.

If you want to disconnect your BMS, be sure to unplug the balance leads first, then B-.

 

[walter-]

I had the feedback the light board is not delivered with the 4S...

 

[Zwy]

I had the feedback the light board is not delivered with the 4S...

It's optional, you have to order just like the other cables. I think on AliExpress is was under 10 bucks. They should just include it and add the cost to the BCM.

 

[walter-]

I phrased it badly; the feedback was that I cannot install it.
I also don't have a connector labeled for it. I only have the uart and an unlabeled connector at the side where I see other BMS have a connector labeled for the indicator.

Walter

 

[Zwy]

That should have the port on the other side with 2 pins, doesn't it?

 

[walter-]

I saw a video where the daly SOC Display is actually connected via a USB connection.
Isn't the Daly tool a usb tool?
It doesn't really measure something ; it reads the data from the device.

 

[Zwy]

I saw a video where the daly SOC Display is actually connected via a USB connection.
Isn't the Daly tool a usb tool?
It doesn't really measure something ; it reads the data from the device.

Mine uses the UART port. I have the display and not the light board. Looks like this.

 

[walter-]

On the UART port I have the bluetooth ;-).

 

[Zwy]

On the UART port I have the bluetooth ;-).

Yes, I have to unplug the display if I want to use the BT connection. It would be nice to have 2 UART ports.

 

[Just John]

This gives directions, connectors and switches you can order from Amazon.

Post in thread 'More DALY smart BMS issues' https://diysolarforum.com/threads/more-daly-smart-bms-issues.19751/post-243904