CCL and DCL always changing between 35A and 70A

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ruip asked Jan 6, '20

CCL and DCL always changing between 35A and 70A

Hi

I have 2 BYD 2,5kWh modules, that each have a 35A Charge Current Limit (CCL) and Discharge Current Limit (DCL), therefore, I would expect to see a continuous 70A CCL/DCL for my system.

However, according to VRM, my CCL/DCL are always fluctuating between 35A and 70A:

It's like this since I installed the system (a few months) and has no noticeable impact in performance (I seem to be able to pull ~50A from the battery, even when the DCL drops to 35A):

Any idea on what's going on?

BYD B-Box Pro firmware 4.17

Multiplus II 3000VA firmware 459

CCGX firmware 2.42

BYD charge current limit

ccl-and-dcl-fluctuating.png (51.3 KiB)

pulling-2671w-53a-with-a-dcl-of-35a.png (57.5 KiB)

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Modifications Space

Node Red Space

Answer 1 · 2020-01-06T20:29:46Z

byd-service answered · Jan 06, 2020 at 08:29 PM

Hello RuiP,

It seems that the communication with the second battery is unstable. Could you check the LED lighting in the batteries and in thw BMU. The BMU should be solid and the batteries shouldn't be scrolling side to side.

Try swapping the communication cables, changing addresses and restarting the system a couple of times, just in case it's just a corrupted record.

2

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ruip commented · Jan 07, 2020 at 09:16 AM

Ok, I will try that in the next 24 hrs.

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ruip commented · Jan 08, 2020 at 06:11 AM

Problem solved!!

I reconnected the communications cable between the modules ans rebooted the modules and voila, now I have steady 70A CCL and DCL!

Thanks for your help!

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20200108-060533.jpg (319.3 KiB)

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