Adaptors & Wiring

RS485 wiring

RS485 requires a twisted pair, this works with CAT5 network cable and RJ-45 connectors.

If the RJ-45 connector on the inverter side is crimped according to T568A/T568B, you can use the pinout in the following table. If the two outermost colors you see on the connector are brown and green, it is probably T568A; if they are brown and orange, it is probably T568B.

RJ45 Pin (inverter side)	Wire Color (when using T568A)	Wire Color (when using T568B)	RS485 pins
1	Green-White	Orange-White	B/D-
2	Green	Orange	A/D+
3	Orange-White	Green-White	GND

TIP

The newer inverters have a combined RS485 and CAN-BUS port. If your battery is already using the port for its CAN-BUS communications, you need to split the cable to connect your RS485 connector. The following articles explains the wiring of the port:

• DIY cable split
• SolarAssistant's RJ45 splitter

USB-to-RS485 adaptors

1. Waveshare USB-to-RS485 example

   This is my preferred adaptor. It includes a GND and lightning/ESD protection, TVS diodes and a resettable fuse.

   

   Waveshare also has a RS485-to-Ethernet module. (which does not work!)

2. USB-to-RS485 adaptor with cable example

   Includes a GND and TVS diode and USB self recovery options.

   

Other tested adaptors

• USB-to-RS485 3 Pin adaptor example

  Includes a GND and TVS diode and USB self recovery options.

• 2-Wire USB-to-RS485 example

  This is the adaptor I started with. It works, but does not include a GND, so your success might vary.

Ethernet-to-RS485 gateways

1. USR-W630 Wifi-to-RS485

   This is a tested Wifi-to-RS485 gateway, which also includes a GND.

   Requires READ_SENSORS_BATCH_SIZE set to 8 or less

2. USR-W610 Wifi-to-RS485

   This is a tested Wifi-to-RS485 gateway. Usually significantly cheaper than the W630, however it does not include a GND.

   Requires READ_SENSORS_BATCH_SIZE set to 8 or less

3. HF5142B Modbus/serial to ethernet (4x RS232/485/422 to 4x E-Ports)

   

   This gateway was tested with the Deye 8k EU Hybrid inverter. The following serial settings were used:

   

Sunsynk Inverters

Sunsynk 3.6kW Inverter

Sunsynk Ecco 3.6kW Hybrid Inverter

Model number: SUN-3.6K-SG04LP1-EU

This likely applies to similar models in the Ecco range: SUN-3K-SG04LP1-24-EU / SUN-3K-SG04LP1-EU / SUN-5K-SG04LP1-EU / SUN-6K-SG04LP1-EU

Closer view of the RS485/CAN port

Sunsynk 5.5kW Inverter

Tested with: USB-to-RS485 adaptor sourced from Banggood, very similar to this.

NOTE: RJ-45 port marked RS485 (bottom right) does not work.

Sunsynk 8.8kW Inverter

Tested with: USB-to-485 adaptor sourced from Micro Robotics, here

Deye Inverters

Deye 8kW Inverter

RS485 is the blue line - top left, as with the Sunsynk inverters. Yellow is the CAN-comms with the Pylontech batteries

Turbo-Energy Inverter

Turbo-Energy 5kW Inverter

Tested with: USB-to-RS485 adaptor sourced from Aliexpress, very similar to this.