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We have encountered a problem with the Smart BMS CL 12-100. The device produces an extremely high voltage drop at 100% charging current (over 1.5V). As a result, the device becomes very warm and the desired charging voltage at the output (14.2V) is only achieved at an input voltage of approx. 15.8V. This means that with a normal charging voltage, almost no charging (only 10%) is possible. This applies to all devices that we have tested in stock. And also with our customers.
We have similar issues with a couple of units - very low charging rate even though the input voltage is quite high (see my open topic here). Does your monitoring screen look similar?
https://community.victronenergy.com/questions/137992/smart-bms-cl-not-charging.html
I had same situation with Smart BMS 12-200, but found a cause and solution.
In my installation the alternator has a sense wire which for LeadAcid you are supposed to connect to the battery + terminal. The function of this wire is to regulate the current produced by the alternator based on the Battery Voltage, which for LeadAcid raises during charging.
For Lithium this voltage curve is flat, and since the voltage remains low, the alternator thinks it has to work harder to keep the current going, and of course the BMS will try to reduce the current causing it to overheat.
I moved the sense wire from the battery+ to the "alternator" terminal of the fuse on the BMS and that solved the problem.
Hope this is helpful
Where did that battery sense wire (originally on battery + and changed to the alternator terminal of the fuse on the bms) actually go to, as in the other end of that sense cable?
