Hello,☹️❣️

I have a solar inverter that gives an F90 error when starting up, accompanied by a continuous beeping sound. The steps I took:

1. Disassemble and clean all components and connections, then reassemble.

2. Attempt to perform a software update using an OTG flash drive, but it didn't work. After a long search, I found a SN number that was somewhat similar to my device.

3. I connected the device to my computer via the micro USB port and downloaded the required software, but it wasn't fully recognized. I suspect I need an R232.

4. I read the entire user manual, but to no avail.

Complete the previous steps thanks to previous articles I was able to access.

Required Information:

Device Model: MAX E 11K

Power: 11kW, 24V System

SN: 96342210100671

From the device interface

U1_ 57.04

U2_ 12.21

From the Watch Power computer application interface

Model type: stand alone

Main CPU version: 0005704

Please help as soon as possible, as I've been in trouble and have been without electricity for a whole week. I'd be very grateful.

If possible, attach the solution with the files.🙏💔🌹

Edited April 4, 20251 yr by bashaar basheer1

Answered in a PM.

Thank you very much I am grateful💚🩵

Answer in pm .

How about sharing the solution with the rest of mankind so if someone else has the same issue with that inverter they can then also be helped from through this forum .

18 hours ago, GMAC said:

How about sharing the solution with the rest of mankind...

I usually do. In this case, fault code 90 is designed to "catch out" clone makers use Voltronic firmware without paying for it. I don't want to help clone makers in any way, if at all possible.

In this unusual case, no patching was required, just updating to the latest firmware.

It sounds like an RS232 connection might be necessary for proper communication. Try using a USB-to-RS232 adapter. Also, make sure the firmware file exactly matches your inverter model and SN.