Troubleshooting RS485 communication on the 4 pin COM port

Created by Roberto Hernandez, Modified on Fri, Apr 18 at 12:34 PM by Eddie De La Torre

This port is a green port located externally on all Solis inverters on the bottom of the inverter.

Pin 1 = +5 volts DC : RED

pin 2 = -5 volts DC : BLACK

Pin 3= +RS485 : YELLOW

Pin 4 = -RS485 : BLUE

Checking the voltage on pins 1 and 2 with a multimeter will ensure power is provided to the communication device (ex: wifi datalogger. The voltage reading should be 5V on DC.

Checking the voltage on pins 3 and 4 with a multimeter will ensure RS485 signal between the inverter and the communication device. RS-485 voltage should read ~1.7Volts on DC

In cases such as the one shown below, where the wires have broken off please refer to the following pin-wire color combination:

Pin 1 = Red

Pin 2 = Black

Pin 3 = Yellow

Pin 4 = Blue

By providing this to the tech, they should be able to solder the wires to the pins.