Disclaimer

This document is not a replacement of official user manual or installation guide of SolaX products. It is intended as a knowledge base to assist solar installers for further details or troubleshooting. All rights are reserved by SolaX Power Network Technology (Zhejiang) Co.,Ltd.

Meter/CT is necessary under the following use cases.

• Zero Feed-in to the grid (Export Control Function);
• Manage Battery to Charge & Discharge (Hybrid or AC Coupled Series);
• Load consumption monitoring;

Compatible Meter List

Compatible Inverter List

Note: ¹ USE CT ONLY;    ² USE METER ONLY;

Take DDSU666-CT 200A/5A - ADD1 for example, it includes the Energy Meter, Current Transformer (200A/5A CT, 1m length), RS485 cable(10m length) and RJ45 connector.

Installation

Please install the meter between the grid and all home loads/other generators.

Below is a typical system diagram of single-phase inverter with a single-phase meter/ CT

The standard meter ADD1 is usually installed at the main distribution box before all home loads, while meter ADD2 can be installed to monitor production from the other PV inverter or generator on the same platform - SolaX Cloud. Below is a typical diagram with one PV inverter and Hybrid/Fit energy storage system solution.

For more system details, please refer to this article Export Control Function

PIN Definition of SolaX Inverter and meter

As shown in the above figure, single-phase meter should be connected to PIN 4&5 at the bottom of the inverter via the RS485 cable. The default length of the cable is 10m. Installer can cut it shorter in accordance with the actual installation condition. If longer length is required, we suggest to use STP (Shielded Twisted Pair) RS485 cable:

If you check the label on smart meter, you will find the connection diagram as below:

• PIN 1&2 connects to L wire and N wire from the mains; 

• PIN 9&10 connects to CT Red and CT Black;

CT Clamp should be clipped onto the L wire of the mains. As mentioned before, the position should be between the grid and all home loads/other generators.

Note: CT arrow should be pointing to the inverter direction

PIN 24&25 connects to PIN 4&5(RS485_A & RS485_B) of SolaX Inverter via RJ45 connector;

Set Export Control function via LCD

For meter or meter with CT, please choose “Meter”;

For standable CT installation, please choose “CT”;

Note: Installer password is required after selecting “Setting”.

For more details, please refer to this article Export Control Function.

Once set, the main screen will start counting down the checking time, and show “Normal” if everything is installed correctly.

Things to check if it shows an error like “Meter Fault”

1. “Meter Fault” indicates the communication between the inverter and meter failed, which means installer should check whether the RS485 cable Pins are correct and firmly connected on both ends.

2. Check whether the meter is bought from SolaX, which should have a SolaX Logo on the meter.

3. Check if “Export Control” is enabled and “Meter” is selected;

4. Check the Modbus address in the setting. By default it should be “1”;

 5. Contact SolaX service team for more assistance.

How to check the meter/CT installation is correct or not

1. Is there an error on the inverter (Refer to Troubleshooting Guide if so)

2. Set the inverter to OFF mode

3. Turn ON some house loads

4. Check the Pgrid value (Press DOWN button on the main screen)
If positive, then the meter/CT direction is reversed.

If negative, then the meter/CT direction is correct.