xaioxang 300a bms seeming to not turn on

[cqcomber]

So I'm new to all this, but have a background in simple electronics for about 10 years now. I bought these 230ah cells and this BMS. I have connected all the wire leads to each cell i thought correctly, and when i plug it into the BMS, all the lights for each battery light up for a split second and then turn off. I've triple checked my wiring and I'm still not sure whats up. Do i have a bad BMS or?

The battery is only there for testing. i have a box I'm designing around for the rest of the project.

 

[profesor79]

the manual is very brief I will say https://macsbatteries.com/images/bms_manuals/Xiaoxiang_BMS_Manual-20220714.pdf
did you check the bms by using the phone application provided?
It could go directly to standby mode, waiting for charge or load, like pylontech batteries.

Check the voltage on the BMS, ensure that it is connected on the negative part of the battery.

 

[cqcomber]

the manual is very brief I will say https://macsbatteries.com/images/bms_manuals/Xiaoxiang_BMS_Manual-20220714.pdf
did you check the bms by using the phone application provided?
It could go directly to standby mode, waiting for charge or load, like pylontech batteries.

Check the voltage on the BMS, ensure that it is connected on the negative part of the battery.

I'm on android, but i cant even see the bms in the list of bluetooth, and it is definately connected to the negative port on the battery.
i currently have it charging on a 100a charger.

 

[42OhmsPA]

Did you verify the wiring is correct by metering the pins in the connector? Starting with main negative voltage steps up incrementally on each connection to the main positive?

 

[cqcomber]

Did you verify the wiring is correct by metering the pins in the connector? Starting with main negative voltage steps up incrementally on each connection to the main positive?

Yup, just did and confirmed this. each one has continuity to the ends.

 

[42OhmsPA]

Yup, just did and confirmed this. each one has continuity to the ends.

Strange.
The B- is going the the battery negative?

Try unplugging Bluetooth and plugging it back in, maybe.

 

[cqcomber]

Strange.
The B- is going the the battery negative?

Try unplugging Bluetooth and plugging it back in, maybe.

yes, its going there.

there is no external bluetooth module, its built in. but i have unplugged and replugged in that connector multiple times

 

[42OhmsPA]

yes, its going there.

there is no external bluetooth module, its built in. but i have unplugged and replugged in that connector multiple times

I'm out of ideas, I've never used that specific model; the 5 other JBDs I'm running work fine.
I'd contact battery hookup tomorrow and see what they have to say.

 

[cqcomber]

I'm out of ideas, I've never used that specific model; the 5 other JBDs I'm running work fine.
I'd contact battery hookup tomorrow and see what they have to say.

I just found out that it might not be a smart bms. Would it be ok to use until i get the jbd 200a bms from ali?

 

[42OhmsPA]

I just found out that it might not be a smart bms. Would it be ok to use until i get the jbd 200a bms from ali?

It might be, how do you know its working?

Is this the same one? https://ezealco.com/product/jbd-bms-battery-management-system-12v-4s/
Claims to be in stock in the US

 

[cqcomber]

It might be, how do you know its working?

Is this the same one? https://ezealco.com/product/jbd-bms-battery-management-system-12v-4s/
Claims to be in stock in the US

Nah, the bms is in my OP. i got it from battery hookup. I don't know that its working since i cant connect to it in any way. For the charger, do i just give it static voltage, or use the 4 stage charging function.(charger)

 

[NIFE]

I bought that model from Battery Hookup. It currently is not being used but if I remember correctly, after the initial power up, none of the lights stay on until you approach around 3.5 volts per cell. At that point, they start flashing on and off depending on which cells are being discharged to balance them out. When charging is stopped or if balancing is complete, all the lights remain off. A word of caution, the unit I have did not shut down at 3.65 per cell when testing the over voltage function. . The shutdown voltage was a little higher. An internet search showed this was normal for this model. It has a higher trip voltage than we are used to. Just hang out when approaching full charge. The lights will start flashing radomly as it balances.

 

[cqcomber]

I bought that model from Battery Hookup. It currently is not being used but if I remember correctly, after the initial power up, none of the lights stay on until you approach around 3.5 volts per cell. At that point, they start flashing on and off depending on which cells are being discharged to balance them out. When charging is stopped or if balancing is complete, all the lights remain off. A word of caution, the unit I have did not shut down at 3.65 per cell when testing the over voltage function. . The shutdown voltage was a little higher. An internet search showed this was normal for this model. It has a higher trip voltage than we are used to. Just hang out when approaching full charge. The lights will start flashing radomly as it balances.

This is exactly what happens with my unit. i have a jbd unit from ali on the way because i want smart monitoring etc. I did have to switch the powermax from battery charging mode to fixed output mode, and set the output voltage to 15.5.

Thanks for your reply

 

[NIFE]

This is exactly what happens with my unit. i have a jbd unit from ali on the way because i want smart monitoring etc. I did have to switch the powermax from battery charging mode to fixed output mode, and set the output voltage to 15.5.

Thanks for your reply

I don't know what a powermax is but 15.5 volts is way too high. Reduce it to no higher than 14.5 volts. 14.0 would be safer yet. there is no need to push the limits with these. They will charge up just fine at the lower voltages recommended above.

 

[cqcomber]

I don't know what a powermax is but 15.5 volts is way too high. Reduce it to no higher than 14.5 volts. 14.0 would be safer yet. there is no need to push the limits with these. They will charge up just fine at the lower voltages recommended above.

i've linked it in previous posts. its a 100a charger/dc converter combo. Even with the "voltage losses" of everything? i was told from a friend that i want the voltage of the charger to be about 5% above for those losses

 

[cqcomber]

I come with one last question. I have a 100a ac-dc converter that has a fixed output range from 11.5-15.5v. To charge my 12v lifep04 battery pack to 90% through the bms what should I set the output of the converter to? Is this the right thing to use to charge my battery? It has a charging function too that's meant for lithium ions but I wasn't sure if it was actually charging anything after about 30 mins. ac-dc converter