SCA60KTL-DO/US-480 Inverter Sent 6553.5 as kW Output After Sunset

[bellington]

I have a 1107 kWh battery with 60 kW PV and a 450 kW generator. On 9/13/25, the generator was running, pushing around 200 kW into the battery, and the inverter had reported 0 amps and 0 kW for about 15 minutes. Around 7:30 pm, the inverter started reporting 6553.3 kW. The battery interpreted this as massive incoming current, and opened the contacts. Obviously, opening the circuit on the generator at 200 kW is not ideal.

Questions:
1. Does anyone know is the 65535 series of numbers is a code for an error, or fault on the Chint inverter?
2. If so, what should I check on the inverter?

Thank you,

Byron

 

[winnie]

65535 is 2^16-1

If you ever see something screwed up and at the same time see a number that is closely related to 2^8, 2^16, or 2^32 then you should suspect a software fault.

Beyond that I don't have experience in this specific field and can't give you a specific answer. Just that the 65535 number raises a red flag for me.

-Jonathan

 

[ModbusMan]

65535 is 2^16-1
If you ever see something screwed up and at the same time see a number that is closely related to 2^8, 2^16, or 2^32 then you should suspect a software fault.

Exactly this, especially when Modbus/RTU is involved. I see it all the time with smart trip units in breakers when there's zero current flow, doubly so when they're open. Thankfully I can the BMS software to ignore it as garbage.

 

[MD Automation]

OP - you mention a report of 6553.3 kW - but you ask about the number 65535. Just curious.

And will agree with the posts about the "number" 65535. In 2's complement math this is equal to -1, if the number in question is a 16 bit signed integer.

All 16 bits set (decimal 65535), for a signed integer, is actually the smallest negative number you can represent (negative 1).

So, that's a red flag to be aware of at times. Some rounding error that drops you a tiny bit below zero can show up "somewhere else" as a huge number if the "somewhere else" does not know the number is a signed integer.

 

[bellington]

OP - you mention a report of 6553.3 kW - but you ask about the number 65535. Just curious.

And will agree with the posts about the "number" 65535. In 2's complement math this is equal to -1, if the number in question is a 16 bit signed integer.

All 16 bits set (decimal 65535), for a signed integer, is actually the smallest negative number you can represent (negative 1).

So, that's a red flag to be aware of at times. Some rounding error that drops you a tiny bit below zero can show up "somewhere else" as a huge number if the "somewhere else" does not know the number is a signed integer.

Good question. Someone else mentioned the 65535 as a flag before I posted. I made the assumption that the 6553.5 was just a controller being bound to only 4 places and it stick the decimal after the 3.

 

[pv_n00b]

Is it normal for inverters to use the power production data output for error messages? I have not heard of that.

 

[bellington]

Is it normal for inverters to use the power production data output for error messages? I have not heard of that.

Good question and part of the reason for my post. I'm not sure at this point of that was the raw data coming from the inverter, or the resulting data AFTER the BESS controller interpreted and applied the inverter data to the kW field.

Thanks for the response.

 

[pv_n00b]

Sounds like you need to review the error history in the inverter. If the BESS controller is getting creative then you can't trust that data. The inverter manual has instructions on accessing the history data. I have never heard of a CPS inverter sending out error codes in the production data field.