Hooking up Daly BMS from LiFePo4 Batteries to Charge Controller

Jades

Hi all,

I just connected a Daly BMS 60amp to two LifePo batteries...when I connect it to the charge controller, the charge controller is not turning on. When I connect positive and negative wires from the battery, the charge controller turns on fine. Is there anything additional that I would have to do with regard to configuring the BMS?

Batteries add up to 12v.

I have the BMS wired up as such


Thanks much,

James

BB.

Does your wiring match this one?

https://m.banggood.com/DALY-BMS-4S-12V-30A-40A-50A-60A-Smart-Battery-Protection-Board-3_2V-18650-BMS-LiFePO4-BMS-with-Bluetooth-UART-RS485-CAN-NTC-Function-p-1823574.html

This is the only diagram I could find.

Also, they said to connect the battery wiring before connecting the balance cables.

Bill

mcgivor

Looking at the image provide it appears to be a 2P 4S 12V nominal setup, the BMS should have 5 sense wires, 1 black, 4 red, the black goes to the main battery negative the reds go to the positives in sequence 1 to 4 see image below, this image is from Daly. 

Jades

Hi Bill,

Thanks. Yes, that is the BMS I have, though I don't have bluetooth. When you say connect the battery wiring--are you referring to the cables on the BMS going to the battery and then to the charger. (I already had the batteries wired up as should in the image). I did try to go directly from the B- (blue cable) to the P- (black cable) and plug into the charge controller and still no dice. I haven't hooked in the solar cables, just because I've heard that the batteries should be hooked into the charge controller first, but perhaps with a BMS, you need to hook in the solar cables before it will work?

Thanks much!

Jades

Yes, there are five sense wires--which I've wired per my diagram. Are you saying that that wiring is incorrect? Else, I have the B- and B+ wired as you show in the Diagram. Should I just try taking everything off and starting over (does the BMS need to be reset by taking everything off?)

mcgivor

One  thing worth mentioning is if there is an inverter connected to the battery, on or not, the BMS will fault as the current needed to initially charge the capacitors will be seen as an overcurrent event and disconnect the battery. Should this be the case you need to bypass the BMS initially to charge the capacitors, once charged the inverter will not cause any problems unless disconnected from the DC supply then reconnected. 

To reset the BMS unplug the sense wires  connector then plug back in.

To avoid sparks when charging the capacitors a series resistor can be used, but this is not essential.

BB.

I did misread the instructions (was on my phone before)--Basically, check the voltages on the connector are correct first, then plug in the connector to the BMS.

McGivor is here. He knows much more about the Li Ion/BMS/etc. setups--I am just looking at the diagrams/basics.

-Bill

Jades

Great. Thanks both.

No inverter at the moment. I've tried unplugging the sense wires connector but didn't seem to do anything. When I checked the voltage between the battery positive and the p- (black cable), I was getting a voltage of 3.2ish (the highest I got depending on where I put the wires was around 11.4. (Still I would think that would be enough to power on the charge controller, so I figured something else was amiss). I'll take a picture tomorrow morning and post here.

mcgivor

What are the individual cell block (2 cells in parallel)  voltage values? They should all be relitivly close, if one is extremely low the BMS will not connect the battery.

Check to verify the red cell sense wires are in the correct sequence, cell 1 being closest to the black, cell 2 second and so forth and ensure all of them have good continuity, especially if crimp terminals are used

What voltage is seen at B+ & B- ? 

There is no setup procedure with the Daly BMS, however if anything is outside the parameters electrically or if any termination is bad or connected incorrectly it will not allow discharge.

Jades

The individual cell block voltage values are 3.35. I top-balanced them, so they are all the same voltage. I used heatshrinking connectors for the BMS sense wires.

The voltage at B+ and B- 13.4

I'll check the terminations again and look at continuity with the heatshrink connectors.

Here is a picture of how I've connected them.

BB.

I don't know--But it appears the Vbatt+ terminal (4th sense lead from negative) is in the wrong position... It should be moved all the way to the "right" / + terminal... I am guessing, but I think the BMS gets both the 4th cell voltage, it also pulls its power from the + connector on the BMS...

Aka, 4th cell/Vbatt+ connects to the "down arrow" in McGivor's post #3.

-Bill

Jades

I tried moving the 4th sense all the way down, so that it is on the pos cable going to the charge controller. (I think that's what you meant). Still no dice.

BB.

I am not sure--But I think you have sense #4 still in the wrong position(???).

You do not want #4 wire going to the charge controller(???)... You want the #4 sense lead (battery + bus connection) going to the other end of the header (around position #7-10 or so--I cannot tell the total number of pins from your photo) of the header connector--The opposite end from the "-" black wire / connector.
Incorrect:
"-"                        "+"
[ ] [ ] [ ] [ ] [ ] [ ] [ ] [ ]
B  1  2  3  4

Correct:
"-"                        "+"
[ ] [ ] [ ] [ ] [ ] [ ] [ ] [ ]
B  1  2  3              4

Be very careful... I don't want you to "fry" the BMS or your battery connections.

-Bill

mcgivor

The sense wires are correct from what I can see, the test I would conduct is to verify the voltage between the negative and each positive on the connector itself, starting with the closest to the black to last, the voltage should increase 3.35V on each, this will verify the sense wires have a sound connection.

What is the odd link between cell block 2 and 3?

Jades

Yes!!! That did the trick. So two of the sense wires had a poor connection because of how I must've installed the heatshrinking wraps. Thanks! In retrospect, I should've done this process prior to and while installing the wraps.

The odd link connects the two ~6.5 volt batteries in series to get the 12v.

I plan to install a 40amp fuse in between the batteries and the charge controller. Is there a particular one you'd recommend? Also, I notice when I connect the BMS to the charge controller there is a bit of a spark. Is that bad for the BMS?

mcgivor

The smallest things are often the problem, good to hear that the problem is resolved, rather than using fuses, consider circuit breakers, they can be reset as opposed to being replaced and are generally accepted as a means of disconnect. Be aware they can be polarity sensitive, if they are, the positive should be connected to the source of highest potential, usually the battery.

Heinppg

Hi All 

Just joined the group, 

I have a question about the Dali BMS if anyone can maybe assist please. 

I have connected my Dali BMS to 14s Lithium ion pack I put together. 

My question, wat type of charger do you connect to the charging port to charge the battery pack. I am not sure if the BMS will take care of the charging (constant current/constant voltage) .Do it need a special Lithium ion charger or just a DC power supply.The DALi wire diagram and wiring instructions do not specify anything.

Thanks in advance 

Regards
Hein

mcgivor

What type of cells, what capacity are they, is this grid or solar charging? Lithium-Ion cells are very sensitive to to their charging profile, using something unsuitable may well be protected by the BMS but will be an annoyance as the charging/discharge will be cut when out of parameter. 

Specific chargers are available however the specifications are required to recommend something, 14S would suggest LIPO for a 48V nominal, details are important.

Heinppg

Hi Mc 
SORRY  for the late response, my pack is a 14s 1p 57Ah lithium ion. The drawing below is the only drawing from Daly showing the connection for a charger. So, the Question was, do I connect n proper lithium ion charger to the c+and c- or do I just connect a 60v dc supply and let the BMS handle the rest.

mcgivor

The chemistry of the lithium cells  is needed to answer the question, the charger should be selected to match the battery chemistry  because voltages per cell vary, it's best to use a dedicated charger with the correct constant voltage value.

Heinppg

Thanks for the Quick response, Appreciate...