The Deye DDSU666CT is a single-phase DIN rail energy meter with RS485 Modbus-RTU communication, designed for precise bidirectional energy measurement in solar PV systems, commercial buildings, and residential applications. It measures voltage, current, frequency, active power, power factor, and both import and export energy — all displayed on a built-in segment LCD. Fully compatible with Deye inverters for zero-export control across Europe. Designed for 230V AC, 50Hz European grid standards.
The DDSU666CT delivers Class 1 accuracy across all measured parameters, supports both direct input (5-80A) and CT input (1.5-6A) connections, and communicates via RS485 Modbus-RTU at configurable baud rates. Its compact DIN 35mm rail form factor installs in minutes. Operating temperature spans -25°C to +55°C, with extreme tolerance up to +70°C. Voltage loop consumption is just ≤1W, minimizing impact on your system's efficiency.
The DDSU666CT measures: positive active energy (import), reverse active energy (export), instantaneous voltage, current, active power, power factor, and grid frequency. All parameters are cyclically displayed on the built-in segment LCD. This comprehensive measurement suite makes it ideal for solar monitoring, grid compliance, and energy auditing in both residential and commercial settings.
The DDSU666CT supports two current connection methods. For direct input, it handles a maximum alternating current of 5(80)A — no external transformer needed. If connected via a Current Transformer (CT), the specification is AC 1.5(6)A, enabling measurement of larger industrial loads beyond 80A. Choose the method that matches your installation's current levels.
The DDSU666CT uses a standard DIN 35mm rail mounting structure and modular design for effortless installation. Simply snap the meter directly onto the guide rail inside your distribution box — no special tools required. Connect the voltage and current wiring to the labeled terminals following the diagram in the Quick Start Guide. Installation typically takes under 10 minutes for a qualified electrician.
The Deye DDSU666CT carries CE marking under the Low Voltage Directive 2014/35/EU and EMC Directive 2014/30/EU. It complies with applicable IEC/EN metering standards for Class 1 accuracy and meets EU requirements for energy metering equipment in both residential and commercial applications. Documentation is available at deyeinverter.com.
Unlike generic meters that only measure import energy, the DDSU666CT offers full bidirectional metering (import and export) — critical for solar PV systems. Its native RS485 Modbus-RTU interface integrates directly with Deye inverters with no additional gateway required. The Class 1 accuracy and -25°C to +55°C operating range exceed many competing meters in the same price bracket, making it the recommended choice for Deye solar installations.
The meter has an RS485 communication interface supporting Modbus-RTU protocol. Default parameters: baud rate 9600 bps, 8 data bits, no parity, 1 stop bit (8N1), communication address 03. To change baud rate or address: long-press the panel button for 3 seconds to enter settings mode, short-press to adjust values. The system exits automatically after 20 seconds of inactivity.
Yes. The specified normal operating temperature range is -25°C to +55°C. Under limited working conditions, the meter withstands extremes from -40°C to +70°C. The annual average relative humidity should not exceed 75%. This wide range makes the DDSU666CT suitable for installations across all European climates — from Nordic winters to Mediterranean summers.
The Deye DDSU666CT comes with a 2-year product warranty. Deye's European support team provides technical assistance via email and official support channels. With over 10 years of manufacturing experience, Deye provides long-term documentation and firmware support for all EU-sold products. All orders include VAT, ship from our European warehouse, and are covered by a 14-day return policy.
