Sungrow DTSU666-20 Three-Phase Smart Energy Meter Quick Installation Guide
Applicability
This manual is applicable to Sungrow Three-phase Smart Energy Meter, model DTSU666-20.
Keep the manual in a convenient place for future reference. The latest manual can be acquired at support.sungrowpower.com.
Target Group
Only qualified personnel with the following skills are allowed to perform the work described in this document:
- Training in the installation and commissioning of electrical systems.
- Capability of coping with dangerous and emergency situations during installation and commissioning.
- Familiarity with country/regional standards and specifications.
- Knowledge of and compliance with this manual and other related documents.
Intended Use
The Smart Energy Meter is designed for indoor use only. It is a measuring device detecting electrical values at the grid-connected point. It cannot be used for billing purposes. Data collected by the Smart Energy Meter on PV power generation may differ from the data of the main Smart Energy Meter.
Any use other than those described in this document does not qualify as appropriate usage and is prohibited. Do not make any modifications to the product.
Damage or destruction may be caused to the Smart Energy Meter due to inappropriate usage. The Smart Energy Meter must not be operated beyond the values specified in the technical data.
[DANGER] Lethal voltages and danger to life due to electric shock!
- Only use the Smart Energy Meter in a dry environment and keep it away from liquids.
- Install the Smart Energy Meter in the switch cabinet only and ensure that the connection areas for the line and the neutral conductors are behind an insulating cover or have contact protection.
- Install an external disconnect switch between the Smart Energy Meter and the grid-connection point. The external disconnector must be close to the Smart Energy Meter and easily accessible.
- Disconnect the Smart Energy Meter from voltage sources before cleaning. The Smart Energy Meter must be cleaned with a dry cloth only.
[WARNING] Fire hazard!
If a fuse is missing or incorrect, a fire may be caused when a fault occurs. This can result in death or serious injury.
Technical Data
| Parameter | DTSU666-20 |
|---|---|
| Nominal voltage | 230Vac L-N / 400Vac L-L |
| Input voltage range | 50 ... 280Vac L-N / 85 ... 485Vac L-L |
| Current Transformer(CT) | ***[1]/0.333V |
| Grid frequency | 50Hz/60Hz |
| Operating temperature | -25 °C to +70 °C |
| Relative humidity | < 75% (non-condensing) |
| Dimensions (W x H x D) | 118 x 72 x 65.5 mm |
[1] *** indicates the input current. Voltage current transformers are suitable for: 100A, 250A, 400A, 500A.
Delivery Contents
Related components in the scope of delivery:
- Smart Energy Meter (DTSU666-20)
- RS485 cable *
- Quick installation guide
- Current Transformer(CT) **
A textual description of the delivery contents image shows the DTSU666-20 meter, a Current Transformer (CT) with two variants, an RS485 cable, and a Quick guide document.
* The RS485 cable is included in the inverter package. If you cannot find the cable, please contact SUNGROW.
** The CT (Current Transformer) is included in the accessories shipped with the inverter. There are 3 CTs if the product is sold to the European region and 2 CTs if the product is sold to the Australian region.
[NOTICE] Contact SUNGROW or the distributor in case of any damaged or missing components.
Three-phase Smart Energy Meter Dimensions
A diagram shows the dimensions of the DTSU666-20 meter. The overall width is 118 mm, height is 72 mm, and depth is 65.5 mm. Specific mounting dimensions are also indicated: 98 mm height for the main body, 53 mm for the terminal cover, 37 mm for the DIN rail clip, and 45 mm and 35 mm for other mounting features.
CT Dimensions
Dimensions for Current Transformers (CTs) are provided. For 100 A CTs, the dimensions are 35.5 mm (width) x 29.8 mm (height) x 15.5 mm (depth), with a left elevation view showing 47 mm (width) x 26.5 mm (height) x 19 mm (depth). For 250 A CTs, the dimensions are 51 mm (width) x 43.5 mm (height) x 24 mm (depth), with a left elevation view showing 77.2 mm (width) x 32.7 mm (height) x 22 mm (depth). The length of the 100 A and 250A CT cables is 8000±20mm. If the CT cable is excessively long, it should be cut to the appropriate length according to the actual on-site situation.
Three-phase Smart Energy Meter and its terminals
A diagram illustrates the DTSU666-20 meter with its terminals labeled A through H. The table below describes the designation and function of each terminal group:
| Designation | Terminals | Description |
|---|---|---|
| A | 2, 5, 8, 10 | Voltage sampling terminals |
| B | - | LCD display |
| C | SET, ESC, → | Keys: SET: confirm selection/settings; ESC: return to previous menu/cancel settings; →: increase setting value |
| D | A, B | Communication terminals |
| E | PQ-, P+ | Reserved |
| F* | 1, 3, 4, 6, 7, 9 | CT1 / Coils1 Current Input |
| G* | 31, 33, 34, 36, 37, 39 | CT2 / Coils2 Current Input |
| H | 91, 92 | Reserved |
* Please remove the shorting wires as needed, and remain the wires for those unused.
Meter Ports and Connections
The meter ports are shown, with CT ports for current detection and L1, L2, L3, N ports for voltage detection.
A diagram shows the terminal connections for CT2 (terminals 31, 33, 34, 36, 37, 39) and CT1 (terminals 1, 3, 4, 6, 7, 9), and voltage sampling (L1 to terminal 2, L2 to terminal 5, L3 to terminal 8, N to terminal 10). The diagram also shows the DTSU666-20 meter with its display and buttons.
A separate diagram illustrates the voltage connections for a three-phase system: L1 connected to terminal 2, L2 to terminal 5, L3 to terminal 8, and N to terminal 10. It notes that if only L1 (to terminal 2) and the neutral conductor (to terminal 10) are connected, the three-phase Smart Energy Meter can be used as a single-phase Smart Energy Meter.
Installation
DIN Rail Mounting: Mount the Smart Energy Meter to a 35 mm DIN rail. Hook it into the top edge of the rail and press down until it snaps into place.
Cable Connection:
- Step 1: Turn off the solar switch, load switch, main switch, and other power switches. Secure them against reconnection.
- Step 2: Take out the RS485 cable from the inverter's packaging.
- Step 3: Connect the plugs A and B to terminals A and B on the Smart Energy Meter. A diagram shows the RS485 cable with plugs A and B connecting to the meter's communication terminals.
Wiring Scenarios
The following scenarios illustrate the wiring of the Sungrow DTSU666-20 Smart Energy Meter with different inverter and grid configurations.
Scenario 1: Three-phase hybrid inverter + Three-phase PV inverter + Three-phase grid
This scenario involves connecting a third-party PV inverter, a Sungrow Hybrid Inverter, the DTSU666-20 Smart Energy Meter, and a Household Meter to a three-phase grid. The diagram shows the third-party PV inverter connected to the grid. The Smart Energy Meter is connected to the grid and the load side. Current transformers (CTs) are shown connected to the meter's CT1 and CT2 terminals, monitoring current from the third-party PV inverter and the Sungrow Hybrid Inverter respectively. The voltage sampling terminals of the meter are connected to L1, L2, L3, and N of the grid. The Sungrow Hybrid Inverter is also connected to the grid and the load. The Household Meter is connected to the grid.
Note: Connect CT2 of the meter only if a third-party PV inverter is used. This channel does not need to be connected if a SUNGROW PV inverter is used.
Scenario 2: Three-phase hybrid inverter + Single-phase PV inverter + Three-phase grid
This setup includes a third-party PV inverter (single-phase), a Sungrow Hybrid Inverter (three-phase), the DTSU666-20 Smart Energy Meter, and a Household Meter connected to a three-phase grid. The diagram shows the third-party PV inverter connected to L1 of the grid. The Smart Energy Meter's voltage terminals are connected to L1, L2, L3, and N of the grid. CTs are connected to monitor currents. The Sungrow Hybrid Inverter is connected to the grid and the load. The Household Meter is connected to the grid.
Scenario 3: Single-phase hybrid inverter + Three-phase PV inverter + Three-phase grid
This configuration features a third-party PV inverter (three-phase), a Sungrow Hybrid Inverter (single-phase), the DTSU666-20 Smart Energy Meter, and a Household Meter connected to a three-phase grid. The diagram shows the third-party PV inverter connected to the grid. The Smart Energy Meter's voltage terminals are connected to L1, L2, L3, and N of the grid. CTs are connected to monitor currents. The Sungrow Hybrid Inverter is connected to the grid and the load. The Household Meter is connected to the grid.
Scenario 4: Single-phase hybrid inverter + Single-phase PV inverter + Three-phase grid
This scenario involves a third-party PV inverter (single-phase), a Sungrow Hybrid Inverter (single-phase), the DTSU666-20 Smart Energy Meter, and a Household Meter connected to a three-phase grid. The diagram shows the third-party PV inverter connected to the grid. The Smart Energy Meter's voltage terminals are connected to L1, L2, L3, and N of the grid. CTs are connected to monitor currents. The Sungrow Hybrid Inverter is connected to the grid and the load. The Household Meter is connected to the grid.
Scenario 5: Single-phase hybrid inverter + Single-phase PV inverter + Single-phase grid
This setup includes a third-party PV inverter (single-phase), a Sungrow Hybrid Inverter (single-phase), the DTSU666-20 Smart Energy Meter, and a Household Meter connected to a single-phase grid. The diagram shows the third-party PV inverter connected to the grid. The Smart Energy Meter's voltage terminals are connected to L and N of the grid. CTs are connected to monitor currents. The Sungrow Hybrid Inverter is connected to the grid and the load. The Household Meter is connected to the grid.
Scenario 6: Two-Phase Grid System
This scenario describes a two-phase grid system with specific voltage configurations: L1 at 180° phase voltage of 230V, line voltage of 460V, and L2 at 120° phase voltage of 230V, line voltage of 400V. The diagram shows a third-party PV IVT, a Sungrow Hybrid Inverter, the DTSU666-20 Smart Energy Meter, and a Household Meter connected to this two-phase grid. The Smart Energy Meter's voltage terminals are connected to L1, L2, and N of the grid. CTs are connected to monitor currents. The Sungrow Hybrid Inverter is connected to the grid and the load. The Household Meter is connected to the grid.
Step 5: CT Direction and Cable Check
After the meter is connected, please check the CT direction and cable installation carefully. The arrow on the CT should always point to the load side.
A diagram illustrates the connections with specific points marked with 'X' indicating incorrect connections. These include incorrect CT placement and incorrect cable connections to the meter terminals.
Checks to perform:
- Whether the CT direction is correct. The arrow on the CT should point to the load side.
- Whether CTs are connected to correct cables. The CT corresponding to IA and IA* should be connected to cable L1, the CT corresponding to IB and IB* should be connected to cable L2, and the CT corresponding to IC and IC* should be connected to cable L3.
- Whether the cables connected to L1, L2, L3, and N terminals of the meter are correct.
- Check carefully whether the clips of the CT's upper and lower parts are snapped into place perfectly; otherwise, the measurement of current may not be accurate.
Step 6 & 7: Final Installation Steps
Step 6: For inverter cable connection, refer to the user manual of the corresponding inverter.
Step 7: Cover the Smart Energy Meter with the insulating cover or contact protection of the sub-distribution. Switch on the power supply to the sub-distribution.
Displayed Function
From the displayed interface, the electrical parameter and energy data are all primary side data (multiplied by current and voltage ratios). The energy measuring value will be displayed with seven bits, with a displaying range from 0.00kWh to 9999999MWh.
The display shows values like voltage (V), current (A), power factor (PF), and active power (kW). A table lists various display interfaces and their corresponding instructions/values:
| No. | Display Interface | Instruction |
|---|---|---|
| 1 | π1 9.600 | Protocol: Modbus-RTU, address=001, Baudrate=9600, None parity, 1 stop bits |
| 2 | ----001 | |
| 3 | UA 220.0 | First channel Phase A voltage =220.0V |
| 4 | UB 220.1 | First channel Phase B voltage =220.1V |
| 5 | UC 220.2 | First channel Phase C voltage =220.2V |
| 6 | IA 5.000 | First channel Phase A current =5.000A |
| 7 | IB 5.001 | First channel Phase B current =5.001A |
| 8 | IC 5.002 | First channel Phase C current =5.002A |
| 9 | PE 3.291kW | First channel Combined phase active power =3.291kW |
| 10 | PA 1.090kW | First channel Combined phase A active power =1.090kW |
| 11 | PB 1.101kW | First channel Combined phase B active power =1.101kW |
| 12 | PC 1.100kW | First channel Combined phase C active power =1.100kW |
| 13 | FE 0.500 | First channel Combined phase power factor PFt=0.500 |
| 14 | FA 1.000 | First channel Combined phase A power factor PFa=1.000 |
| 15 | FB 0.500 | First channel Combined phase B power factor PFb=0.500 |
| 16 | FC-0.500 | Second channel Combined phase power factor PFc=-0.500 |
| 17 | UA 220.0 | Second channel Phase A voltage =220.0V |
| 18 | UB 220.1 | Second channel Phase B voltage =220.1V |
| 19 | UC 220.2 | Second channel Phase C voltage =220.2V |
| 20 | A 5.000 | Second channel Phase A current =5.000A |
| 21 | B 5.001 | Second channel Phase B current =5.001A |
| 22 | C 5.002 | Second channel Phase C current =5.002A |
| 23 | PE 3.291kW | Second channel Combined phase active power =3.291kW |
| 24 | PA 1.090kW | Second channel Combined phase A active power =1.090kW |
| 25 | PB 1.101kW | Second channel Combined phase B active power =1.101kW |
| 26 | PC 1.100kW | Second channel Combined phase C active power =1.100kW |
| 27 | FE 0.500 | Second channel Combined phase power factor PFt=0.500 |
| 28 | FA 1.000 | Second channel Combined phase A power factor PFa=1.000 |
| 29 | FB 0.500 | Second channel Combined phase B power factor PFb=0.500 |
| 30 | FC-0.500 | Second channel Combined phase C power factor PFc=-0.500 |
Communication Settings: The communication address of Modbus protocol is 1 decimal data (1 ~ 254). The factory default baud rate is 9600bps, N.8.1. E1 means even check one stop bit, 01 means odd check one stop bit, N2 means two stop bits without check, N1 means one stop bits without check.
When RS485 is communicating, the telephone sign [symbol for phone/signal] will flash.
Programming Parameter
The parameters of the meter equipped only with 100A/0.333VCT have been set before delivery and can be installed directly after acceptance, without setting parameters again. Meters equipped with other CT and Rogwski coils need to set their parameters before installation.
| Parameter | Value range | Description |
|---|---|---|
| CT Type | 1~8 | 1: CT01:100A/333mV, 2: CT02:250A/333mV, 3: CT03:400A/333mV, 4: CT04:500A/333mV, 5: RS01:1000A/333mV, 6: RS02:2000A/333mV, 7: RS03:3000A/333mV, 8: RS04:4000A/333mV |
| Pt | 0.1 ~ 1.0 | Voltage ratio, used for setting the voltage ratio of the input loop. When voltage is connected via transformer, Pt = rated voltage of primary loop / rated voltage of secondary circuit. When directly connected, Pt shall be set as 1.0. |
| Prot | Settings for communication stop bit and Parity bits: 1: 645mode, 2: None parity, 2 stop bits, n.2, 3: None parity, 1 stop bit, n.1, 4: Even parity, 1 stop bit, E.1, 5: Odd parity, 1 stop bit, O.1 | |
| baud | 0~3 | Communication baud rate: 0: 1.200 bps, 1: 2.400 bps, 2: 4.800 bps, 3: 9.600 bps |
| Addr | 1 ~ 254 | Communication address |
| nEt | 0: n.34, 1: n.33 | Option for wiring mode: 0: n.34 represents three phase four wire, 1: n.33 represents three phase three wire |
| PLus | 0: P0, 1: P1 | Pulse output: P0: First channel active energy pulse, P1: Second channel active energy pulse |
| d1SP | 0 ~ 30 | Display in turns (second): 0: Timely display, 1~30: Time interval of actual display |
| bLcd | 0 ~ 30 | Backlight lighting time control (minute): 0: Normally light, 1~30: Backlight lighting time without button operation |
Button Description: “SET” represents "confirm" or "cursor shift" (when inputting digits). “ESC” represents "exit", and “→” represents "add". The password is 701 by default.
A diagram illustrates the programming interface navigation using SET, ESC, and Add buttons for setting code, communication address, and baud rate.
Troubleshooting
A table lists common fault phenomena, their reason analysis, and elimination methods:
| Fault phenomenon | Reason analysis | Elimination method |
|---|---|---|
| No display after the instrument being powered on | 1. Incorrect wiring mode. 2. Abnormal voltage supplied for the instrument. | 1. If wiring mode is incorrect, please connect based on the correct wiring mode. 2. If supplied voltage is abnormal, please supply the voltage per the instrument specification. |
| Abnormal RS485 communication | 1. The RS485 communication cable is disconnected, short circuit or reversely connected. 2. The address, baud rate, data bit, and parity bit of the instrument are not in accordance with the inverter. | 1. If any problems with the communication cable, please change the cable. 2. Set the address, baud rate, data bit, and parity bit of the instrument to be the same as the inverter through buttons and the "parameter setting". |
| Power metering inaccuracy | 1. Wrong wiring, please check whether the corresponding phase sequence of voltage and current is correct. 2. Check whether the high and low ends of the current transformer inlet are reversely connected. Pa, Pb, and Pc are abnormal if the values are negative. | 1. For wrong wiring, please connect based on the correct wiring mode. 2. If a negative value is displayed, change the cable connection mode of the current transformer to ensure that the high and low ends are connected properly. |
