Charger1 G003 - Smart Alternator

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.

1 Like

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!

Hi. I to had this error and got a replacement charger after emailing Bluetti and it done the same. I think I have solved the issue. I had a 12v plug into the 12v outlet on the ac180. DC was not on but when I unplugged it (after trying various combinations of the AC inlet, AC outlet, DC input) I discovered the error went away when I unplugged the 12v plug. Having read the notes above and sketching out my 12v system and tracing I discovered that whilst almost all the 12v supplies had positive and negative going from and back to the AC180 one had an negative connection to the van chassis. I used a multimeter on the negative terminal on the 12v plug and tested this to the van chassis. I got a very low reading indicating there was a connection between the negative and the van chassis.The person that installed the diesel heater had chosen to connect the heater negative of the supply to the van chassis as well. Possibly thinking it was good to “earth” the unit. When I disconnected this chassis connection the charger worked not only on silent but also full power. Clearly there was a parallel negative return to the van battery. So anyone with the error check that all negative from 12v systems come back to the power bank and do not connect to van chassis. A simple multimeter between the negative of your 12v supply and van chassis should be infinity ie open circuit. Hope this helps someone else.

So a little update fitting the Victron Energy Orion XS unit into the signal chain has stopped the error G003 appearing however for some reason the Charger 1 keeps cycling power aka it charges for a few seconds then stops and turns off then back on (repeat) @BLUETTI_CARE any ideas?

Hi @Audiotech1986, When the input voltage is insufficient, Charger 1 will repeatedly attempt to charge but keep failing. Could you please confirm whether the input voltage is stable? It would be best if you can take a video to show us its performance during charging.
Additionally, are there no longer any error codes displayed on the app?

Its odd because although the voltage is now stable and the eror codes have stopped it does seem to keep cycling power one thought might be the alternator cycles the power i wonder if the VW alternator may be cycling power to the units due to it maybe being a smart alternator