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 to cope 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 and cannot be used for billing purposes. Data collected by this meter on PV power generation may differ from the main Smart Energy Meter. Any use other than described herein is prohibited. Modifications to the product are not permitted. Inappropriate usage can cause damage or destruction to the Smart Energy Meter; it must not be operated beyond specified technical data values.
[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, ensuring connection areas for line and 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. This disconnector must be close to and easily accessible from the Smart Energy Meter.
- Disconnect the Smart Energy Meter from voltage sources before cleaning. Clean the Smart Energy Meter with a dry cloth only.
[WARNING] Fire hazard!
If a fuse is missing or incorrect, a fire may be caused when a fault occurs, potentially resulting in death or serious injury.
Technical Data
| Parameters | 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 ... +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) **
The RS485 cable is included in the inverter package. If the cable is not found, 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.
Contact SUNGROW or the distributor in case of any damaged or missing components.
Smart Energy Meter Dimensions: The meter has dimensions of approximately 118mm width, 72mm height, and 65.5mm depth. Specific internal dimensions and terminal block layouts are detailed in diagrams.
CT Dimensions
100 A CT: Dimensions are 35.5 mm (width) x 29.8 mm (height) x 15.5 mm (depth). The left elevation shows a depth of 19 mm. The CT is rated 100A/333mV.
250 A CT: Dimensions are 51 mm (width) x 43.5 mm (height) x 24 mm (depth). The left elevation shows a depth of 21.1 mm. The CT is rated 250A/333mV.
The length of the 100 A CT and 250A CT cables is 8000±20mm. If the CT cable is excessively long, it can be cut to the appropriate length according to the actual on-site situation.
Three-phase Smart Energy Meter and its terminals
The meter features a terminal block for connections. The terminals are designated as follows:
| Designation | Terminals | Description |
|---|---|---|
| A | 2, 5, 8, 10 | Voltage sampling terminals |
| B | - | LCD display |
| C | - | Key (SET: confirm/select, ESC: return/cancel, →: increase 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 shorting wires as needed and retain wires for unused terminals.
The meter ports are used for current detection via CT ports and voltage detection via L1, L2, L3, N ports.
NOTICE: 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
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
- Turn off solar switch, load switch, main switch, and other power switches. Secure them against reconnection.
- Take out the RS485 cable from the inverter's packaging.
- Connect the plugs A and B to terminals A and B on the Smart Energy Meter.
Wiring Scenarios
The following scenarios illustrate wiring connections for the Smart Energy Meter with different inverter configurations.
Scenario 1: Three-phase hybrid inverter + Three-phase PV inverter + Three-phase grid
This setup involves a three-phase grid, a three-phase hybrid inverter, and a three-phase PV inverter. The Smart Energy Meter is installed in series with the grid and load. CTs are connected to L1, L2, and L3 lines for current measurement. Voltage is sampled from L1, L2, L3, and N lines.
Scenario 2: Three-phase hybrid inverter + Single-phase PV inverter + Three-phase grid
This configuration includes a three-phase grid, a three-phase hybrid inverter, and a single-phase PV inverter. The Smart Energy Meter connections are similar to Scenario 1, adapted for the single-phase PV inverter.
Scenario 3: Single-phase hybrid inverter + Three-phase PV inverter + Three-phase grid
This setup features a three-phase grid, a single-phase hybrid inverter, and a three-phase PV inverter. The Smart Energy Meter is wired according to the three-phase grid requirements.
Scenario 4: Single-phase hybrid inverter + Single-phase PV inverter + Three-phase grid
This configuration involves a three-phase grid, a single-phase hybrid inverter, and a single-phase PV inverter. The Smart Energy Meter is connected to the three-phase grid.
Scenario 5: Single-phase hybrid inverter + Single-phase PV inverter + Single-phase grid
This setup includes a single-phase grid, a single-phase hybrid inverter, and a single-phase PV inverter. The Smart Energy Meter is connected to the single-phase grid.
Post-Connection Checks
After connecting the meter, perform the following checks carefully:
- CT Direction: Ensure the arrow on the CT points towards the load side.
- CT Cable Connections: Verify that CTs are connected to the correct cables. The CT corresponding to IA and IA* should connect to cable L1, the CT for IB and IB* to cable L2, and the CT for IC and IC* to cable L3.
- Voltage Terminal Connections: Confirm that the cables connected to the L1, L2, L3, and N terminals of the meter are correct.
Displayed Function
The meter's display shows primary side electrical parameters and energy data, multiplied by current and voltage ratios. Energy values are displayed with seven bits, ranging from 0.00kWh to 9999999MWh.
Display Interface and Instructions
| No. | Display Interface | Instruction | No. | Display Interface | Instruction |
|---|---|---|---|---|---|
| 1 | π1 9.600 | Protocol: Modbus-RTU address=001 Baudrate=9600 None parity, 1 stop bits |
16 | FC-0.500 | First channel Combined phase power factor PFc=-0.500 |
| 2 | ----001 | - | 17 | UA 220.0 | Second channel Phase A voltage =220.0V |
| 3 | UA 220.0 | First channel Phase A voltage =220.0V |
18 | UB 220.1 | Second channel Phase A voltage =220.1V |
| 4 | UB 220.1 | First channel Phase A voltage =220.1V |
19 | UC 220.2 | Second channel Phase A voltage =220.2V |
| 5 | UC 220.2 | First channel Phase A voltage =220.2V |
20 | IA 5.000 | Second channel Phase A voltage =5.000A |
| 6 | IA 5.000 | First channel Phase A voltage =5.000A |
21 | IB 5.001 | Second channel Phase A voltage =5.001A |
| 7 | IB 5.001 | First channel Phase A voltage =5.001A |
22 | IC 5.002 | Second channel Phase A voltage =5.002A |
| 8 | IC 5.002 | First channel Phase A voltage =5.002A |
23 | PE 3.291 | Second channel Combined phase active power =3.291kW |
| 9 | PE 3.291kW | First channel Combined phase active power =3.291kW |
24 | PA 1.090kW | Second channel Combined phase active power =1.090kW |
| 10 | PA 1.090kW | First channel Combined phase active power =1.090kW |
25 | PB 1.101kW | Second channel Combined phase active power =1.101kW |
| 11 | PB 1.101kW | First channel Combined phase active power =1.101kW |
26 | PC 1.100kW | Second channel Combined phase active power =1.100kW |
| 12 | PC 1.100kW | First channel Combined phase active power =1.100kW |
27 | FE 0.500 | Second channel Combined phase power factor PFt=0.500 |
| 13 | FE 0.500 | First channel Combined phase power factor PFt=0.500 |
28 | FA 1.000 | Second channel Combined phase power factor PFa=1.000 |
| 14 | FA 1.000 | First channel Combined phase power factor PFa=1.000 |
29 | FB 0.500 | Second channel Combined phase power factor PFb=0.500 |
| 15 | FB 0.500 | First channel Combined phase power factor PFb=0.500 |
30 | FC-0.500 | Second channel Combined phase power factor PFc=-0.500 |
The communication address of Modbus protocol is 1 decimal data (1 ~ 254), and the factory default baud rate is 9600bps, N.8.1. E1 means even check one stop bit, O1 means odd check one stop bit, N2 means two stop bits without check, N1 means one stop bit without check. When RS485 is communicating, the telephone sign will flash.
Programming Function
Parameters for meters equipped with 100A/0.333VCT are pre-set. Meters with other CT and Rogowski coils may require parameter setting before installation.
Programming Parameters
| Parameter | Value range | Description |
|---|---|---|
| CT | 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. If voltage is connected via transformer, Pt = rated voltage of primary loop / rated voltage of secondary circuit. If directly connected, Pt = 1.0. |
| Prot | 1: 645, 2: n.2, 3: n.1, 4: E.1, 5: O.1 | Settings for communication stop bit and Parity: 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: 1.200, 1: 2.400, 2: 4.800, 3: 9.600 | 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 |
| d15P | 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
Button Description: "SET" confirms selection or shifts the cursor. "ESC" exits the current menu or cancels settings. "→" increases the setting value. The default password is 701.
When inputting digits, "SET" can act as a cursor movement button, "→" is the increment button, and "ESC" exits the programming interface or switches to character interface from digit modification. Digits can be set up to the maximum value.
Troubleshooting
| Fault Phenomenon | Reason Analysis | Elimination Method |
|---|---|---|
| No display after the instrument being powered on | 1. Incorrect wiring mode. 2. Abnormal voltage supplied to the instrument. |
1. Connect based on the correct wiring mode. 2. Supply voltage according to the instrument specification. |
| Abnormal RS485 communication | 1. RS485 communication cable is disconnected, short-circuited, or reversely connected. 2. Instrument's address, baud rate, data bit, and parity bit do not match the inverter. |
1. Replace the communication cable if faulty. 2. Set the instrument's address, baud rate, data bit, and parity bit to match the inverter via parameter settings. |
| Power metering inaccuracy | 1. Wrong wiring; check if the phase sequence of voltage and current is correct. 2. High and low ends of the current transformer inlet are reversely connected. (Pa, Pb, Pc are abnormal if values are negative). |
1. Correct the wiring according to the correct wiring mode. 2. If negative values are displayed, change the current transformer cable connection mode to ensure proper connection of high and low ends. |
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