BMS problem

Batteries, Chargers, and Battery Management Systems.
Post Reply
yachtbau
1 µW
1 µW
Posts: 3
Joined: Dec 17, 2017 7:03 pm

BMS problem

Post by yachtbau » Dec 17, 2017 7:18 pm

Hi BMS problems too :?:

Has anyone had experience with these BMS cards? They are available from ebay or amazon for about $15, yet have manufacture errors in alignment of the chip sets. If the uploaded images come through, I've highlighted a 1 mm chip that is 1 mm out of alignment in the exact same spot across all 4 cards. The engineer who built the battery recons it doesn't make a difference. But the battery pack doesn't discharge properly.
IMG_20171216_201756 (1).jpg
closeup
IMG_20171216_201756 (1).jpg (224.85 KiB) Viewed 85 times
What are your thoughts? Defect or not defective?
Its column B11+ (see the brand name text. Go 3 down 3 across and theres the tiny offset chip)
BMSfail.jpeg
BMS fail

yachtbau
1 µW
1 µW
Posts: 3
Joined: Dec 17, 2017 7:03 pm

BMS card warning

Post by yachtbau » Dec 18, 2017 12:06 am

I hope this helps others who might have purchased these very messy BMS cards.

Has anyone had experience with these BMS cards? They are available from ebay or amazon for about $15, yet have manufacture errors in alignment of the chip sets. If the uploaded images come through, I've highlighted a 1 mm chip that is 1 mm out of alignment in the exact same spot across all 4 cards.
IMG_20171216_201756 (1).jpg
IMG_20171216_201756 (1).jpg (224.85 KiB) Viewed 93 times
The engineer who built the battery recons it doesn't make a difference. But the battery pack doesn't discharge properly.
BMSfail.jpeg
What are your thoughts? Defect or not defective?
How would the error show up? I first ID it using a volt meter. Only one cell column ever discharged and completely discharged, beyond recovery.

Any thoughts greatly appreciated.
For more info; the web address of gzlspcb is http://www.gzlspcb.com/col.jsp?id=103
#GZLS PCB The company is Foshan Li-Powered Electronic Technology Co., Ltd
Last edited by yachtbau on Dec 18, 2017 6:50 am, edited 1 time in total.

User avatar
fechter
100 GW
100 GW
Posts: 11989
Joined: Dec 31, 2006 3:23 pm
Location: California Bay Area, USA

Re: BMS problem

Post by fechter » Dec 18, 2017 1:41 am

It could be a manufacturing mistake or it could be intentional.
Is the corresponding resistor on the other channels the same value? Are the traces going to the same corresponding parts?

One test would be to take a non-working board and move the resistor over to what looks like the right position and see if that fixes the problem.
"One test is worth a thousand opinions"

yachtbau
1 µW
1 µW
Posts: 3
Joined: Dec 17, 2017 7:03 pm

Re: BMS card warning

Post by yachtbau » Dec 18, 2017 5:14 am

Attached pics of the back.
bms_back.jpeg
BMS Back2.jpg

Post Reply