Sungrow DTSU666-20 Three-Phase Smart Energy Meter

Applicability

This manual is applicable to Sungrow Three-phase Smart Energy Meter, specifically the DTSU666-20 model. It is recommended to keep the manual in a convenient place for future reference. The latest version can be found at support.sungrowpower.com.

Target Group

This document is intended for qualified personnel trained in the installation and commissioning of electrical systems. Users should be capable of handling dangerous and emergency situations, be familiar with regional standards, and understand this manual and related documents.

Intended Use

The Smart Energy Meter is designed for indoor use only and measures electrical values at the grid-connected point. It is not intended for billing purposes. Data collected may differ from the main Smart Energy Meter. Any use outside of this scope is prohibited, and modifications to the product are not allowed. Inappropriate usage can lead to damage or destruction of the Smart Energy Meter.

The following diagrams illustrate application examples of the Smart Energy Meter in a PV system:

Application Example 1:

A system with PV strings connected to a Hybrid Inverter, which then connects to a Load and a Meter. The Meter is also connected to a Main switch, Main fuse/breaker, Network meter, and the Utility grid. Solar switch and Load switch are also present.

Application Example 2:

A system with PV strings connected to a PV Inverter, which then connects to a Load and a Meter. The Meter is also connected to a Main switch, Main fuse/breaker, Network meter, and the Utility grid. Solar switch and Load switch are also present.

Safety Precautions

DANGER

• Lethal voltages and danger to life due to electric shock.
• Use the Smart Energy Meter only in a dry environment, away from liquids.
• Install the meter in a switch cabinet, ensuring connection areas for line and neutral conductors are protected.
• Install an external disconnect switch between the meter and the grid-connection point, ensuring it is accessible.
• Disconnect the meter from voltage sources before cleaning; use only a dry cloth.

WARNING

• Fire hazard: Missing or incorrect fuses can cause fires, leading to death or serious injury.

Technical Data

Delivery Contents

Related components in the scope of delivery include:

• Smart Energy Meter (DTSU666-20)
• RS485 cable
• Quick installation guide

Visual representation of the DTSU666-20 meter, an RS485 cable, and a quick guide document.

Dimensions

Three-phase Smart Energy Meter dimensions:

Width: 72 mm, Height: 118 mm, Depth: 65.5 mm (main unit), 53 mm (side view), 37 mm (side view), 45 mm (side view), 35 mm (back view).

100 A CT dimensions:

Width: 35.5 mm, Height: 47 mm, Depth: 20.8 mm (main), 15.5 mm (main), 19 mm (left elevation), 26.5 mm (left elevation).

250 A CT dimensions:

Width: 51 mm, Height: 77.2 mm, Depth: 43.5 mm (main), 24 mm (main), 24.9 mm (left elevation), 21.1 mm (left elevation), 32.7 mm (left elevation), 42 mm (left elevation).

Note: The current transformer (CT) is shipped separately or with the inverter.

Three-phase Smart Energy Meter and its terminals

The Smart Energy Meter has terminals labeled A through G, with specific functions:

• A (Terminals 2, 5, 8, 10): Output terminals to the load side.
• B (LCD display): Displays active energy and reactive energy.
• C (Key): SET (confirm/shift), ESC (return/cancel), → (increase value).
• D (A, B): Communication terminals.
• E (Terminals 1, 3, 4, 6, 7, 9): CT1 Current Input.
• F (Terminals 31, 33, 34, 36, 37, 39): CT2 Current Input.
• G (Terminal 91): Power supply of Rogowski coil (5V).

Installation

Mount the Smart Energy Meter to a 35 mm DIN rail by hooking it into the top edge and pressing down until it snaps into place.

Cable Connection:

• The line conductor L1 powers the Smart Energy Meter. Connect L1 and the neutral conductor to terminals 2 and 10, respectively.
• For single-phase use, connect L1 to terminal 2, L2 to terminal 5, or L3 to terminal 8, along with the neutral conductor to terminal 10.
• Step 1: Turn off all power switches (solar, load, main) and secure them.
• Step 2: Obtain the RS485 cable from the inverter or meter packaging.
• Step 3: Connect plugs A and B to terminals A and B on the Smart Energy Meter.
• Step 4: Strip wire insulation by 10 mm and connect wires to the Smart Energy Meter terminals (cross-section: 1mm² to 6mm²).

Retrofit Scenarios:

Scenario 1: Three-phase hybrid inverter + Three-phase PV inverter + Three-phase grid

Diagram shows connections for Hybrid Inverter (IA*, IA, IB*, IB, IC*, IC), PV Inverter, Load, and the DTSU meter with CT connections.

Scenario 2: Three-phase hybrid inverter + Single-phase PV inverter + Three-phase grid

Diagram shows connections for Hybrid Inverter (IA*, IA), PV Inverter, Load, and the DTSU meter with CT connections.

Scenario 3: Single-phase hybrid inverter + Single-phase PV inverter + Single-phase grid

Note: Connect CT1 to terminals 1 and 3; CT2 to terminals 31 and 33.

Diagram shows connections for Hybrid Inverter, PV Inverter, Load, and the DTSU meter with CT connections.

For details on current transformer installation and connection, refer to the information on the side of the current transformer.

NOTICE:

• Ensure CT direction is consistent with the arrow direction.
• Torque specifications for terminal screws: 2, 5, 8, 10 (1.7N.m max, 1.0 ± 0.1 N.m recommended); 13, 14, 16, 17, 19, 21, 24, 25 (0.4N.m max, 0.20 ± 0.05 N.m recommended).
• Step 5: For inverter cable connection, consult the corresponding inverter's user manual.
• Step 6: Cover the Smart Energy Meter with the insulating cover or contact protection. Switch on the power supply.

Displayed Function

The meter displays electrical parameters and energy data from the primary side. The energy measuring value is shown with seven digits, ranging from 0.00kWh to 9999999MWh.

The display interface shows various parameters and their instructions:

• No. 1: Display: π1 9.600, Instruction: Protocol: Modbus-RTU address=001, Baudrate=9600, None parity, 1 stop bit.
• No. 2: Display: ----001, Instruction: First channel Phase A voltage =220.1V.
• No. 3: Display: UA 220.0, Instruction: First channel Phase A voltage =220.0V.
• No. 4: Display: Ub 220.1, Instruction: First channel Phase A voltage =220.1V.
• No. 5: Display: UC 220.2, Instruction: First channel Phase A voltage =220.2V.
• No. 6: Display: IA 5.000, Instruction: First channel Phase A voltage =5.000A.
• No. 7: Display: IB 5.001, Instruction: First channel Phase A voltage =5.001A.
• No. 8: Display: IC 5.002, Instruction: First channel Phase A voltage =5.002A.
• No. 9: Display: PE 3291W, Instruction: First channel Combined phase active power =3.291kW.
• No. 10: Display: PA 1.090kW, Instruction: First channel Combined phase active power =1.090kW.
• No. 11: Display: Pb 1.101kW, Instruction: First channel Combined phase active power =1.101kW.
• No. 12: Display: PC 1.100kW, Instruction: First channel Combined phase active power =1.100kW.
• No. 13: Display: FE 0.500, Instruction: First channel Combined phase power factor PFt=0.500.
• No. 14: Display: FA 1.000, Instruction: First channel Combined phase power factor PFa=1.000.
• No. 15: Display: Fb 0.500, Instruction: First channel Combined phase power factor PFb=0.500.
• No. 16: Display: FC-0.500, Instruction: First channel Combined phase power factor PFc=-0.500.
• No. 17: Display: UA 220.0, Instruction: Second channel Phase A voltage =220.0V.
• No. 18: Display: Ub 220.1, Instruction: Second channel Phase A voltage =220.1V.
• No. 19: Display: UC 220.2, Instruction: Second channel Phase A voltage =220.2V.
• No. 20: Display: IA 5.000, Instruction: Second channel Phase A voltage =5.000A.
• No. 21: Display: IB 5.001, Instruction: Second channel Phase A voltage =5.001A.
• No. 22: Display: IC 5.002, Instruction: Second channel Phase A voltage =5.002A.
• No. 23: Display: PE 3291W, Instruction: Second channel Combined phase active power =3.291kW.
• No. 24: Display: PA 1.090kW, Instruction: Second channel Combined phase active power =1.090kW.
• No. 25: Display: Pb 1.101kW, Instruction: Second channel Combined phase active power =1.101kW.
• No. 26: Display: PC 1.100kW, Instruction: Second channel Combined phase active power =1.100kW.
• No. 27: Display: FE 0.500, Instruction: Second channel Combined phase power factor PFt=0.500.
• No. 28: Display: FA 1.000, Instruction: Second channel Combined phase power factor PFa=1.000.
• No. 29: Display: Fb 0.500, Instruction: Second channel Combined phase power factor PFb=0.500.
• No. 30: Display: FC-0.500, Instruction: Second channel Combined phase power factor PFc=-0.500.

Communication Settings:

• Modbus protocol communication address: 1-254.
• Factory default baud rate: 9600bps, N.8.1.
• E1: even parity, one stop bit. 01: odd parity, one stop bit. N2: two stop bits without check. N1: one stop bit without check.
• When RS485 is communicating, the telephone sign will flash.

Programming Function

Meter parameters are pre-set before delivery. No further parameter setting is required upon installation.

Programming Parameter Table:

Button Operations:

SET: confirm or shift cursor. ESC: exit. →: add. Default password: 701.

Programming Interface Navigation:

Input digits can be used as cursor or motion button. The '→' button adds values. 'ESC' exits the programming interface or switches to character interface. Digits can be modified from the beginning after reaching the maximum value.

Troubleshooting