Hi @Audiotech1986, We would like to explain why Charger 1 reports G003 (input overcurrent). Typically, this issue is caused by the common grounding of the input and output.
Please refer to the figure below. The green arrow indicates the current flowing out from the positive pole, the blue arrow indicates the current returning through the negative pole, and the yellow arrow indicates that part of the current flows back to the negative pole through the frame.
First, Charger 1 adopts a negative pole sampling scheme for current sampling. The output current limit of Charger 1 is 10A, and it will report an overload when the sampled current exceeds 10A. Secondly, when both the input negative pole and the output negative pole of Charger 1 are connected to the car frame (that is, the input and output share the same negative pole), during the operation of Charger 1, the current flows out from the positive pole (green arrow), and when returning through the negative pole (blue arrow), part of the current flows back to the battery’s negative pole through the frame (yellow arrow).
The relationship between the three is: green = blue + yellow. Since we have limited the blue current to 10A, the green current will inevitably exceed 10A. That is to say, under this working condition, the actual output current of Charger 1 is greater than the designed rated current (similarly, the power is also greater than the rated power), so the actual input power (current) will exceed the rated value, resulting in the overcurrent error.
Regarding grounding, please refer to the figure below. The top two are wrong demonstrations, and the bottom two are correct ones.
@BLUETTI_CARE thankyou so much for taking the time to explain in lamens terms what the fault could be and where the fault may occur I will certainly check there are no shorts to ground in my system and / or anything weird happening in my system which I have also draw for you.
As you can see I don’t have anything going to chassis ground as I prefer to know where my electricity is going.
Old electricians habit.
Hi @Audiotech1986, We are not quite sure what the part circled in blue specifically is. Could you please explain it?
Also, what are the specific functions of the remote switch and the 100A relay? What is the load?
In addition, could you test the working status of charger 1 when the remote switch is disconnected and closed, respectively?
We also noticed from the diagram that the negative pole of the battery is not connected to the frame. Is that the case?
@BLUETTI_CARE the circled area is the coil for the relay to turn the Charger 1 on. The purpose of the remote switch is the abilty for a panic button to disable the Charger 1 in case of emergency shutdown, the reason for the relay being so large is because that was all i had in stock.
When the remote switch is on (normal position and circuit closed) the relay is active and allows the charger 1 to work, when remote switch is in off position the charger 1 is deactivated and power to it is cut.
Nothing is sent to chassis as i didn’t wire it that way, old school electrician so i don’t run cables to chassis for ease i run two core 6mm cable from battery to circuit.
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Hi @Audiotech1986, Thank you for confirming — it looks like your wiring is correct.
It’s possible that the battery voltage is too high. Installing a voltage regulator to lower the voltage before testing might help.
We look forward to hearing your test results.
Wishing you the best of luck!
