The SolaX CHINT DTSU666-CT is a three-phase indirect (CT-connected) energy meter supplied with three 200A/5A CTs. Made by CHINT and specified by SolaX, it works with SolaX three-phase inverters and measures import, export and total power and energy on systems of 200A or below.
Its built-in display lets you read power, energy, voltage and current directly on the meter, without logging in to the SolaX app, alongside a number of other electrical parameters. It communicates with the inverter over RS485 Modbus-RTU (9600bps by default) and mounts on a 35mm DIN rail at 72mm wide.
The design is fuse-free, fully sealed and naturally cooled, with Class C (0.5S) accuracy. It is intended for indoor installation on the wall or in a distribution board.
3P4W / 3P3W
Three-Phase Grid
200A/5A
3 CTs Included
Up to 200A
System Size
Class C
Accuracy (0.5S)
RS485
Modbus-RTU
72mm
DIN-Rail Width
Systems Up to 200A
SolaX designs this meter for systems of 200A or below, using the supplied 200A/5A CTs. For larger supplies choose a meter and CTs rated for the current, such as the SolaX M3-40 with higher-rated 40mA CTs.
5A CTs, Not 40mA CTs
This meter takes 5A-output CTs. The CTs used with SolaX M-series meters are 40mA-output and are not interchangeable. Use the CTs supplied with this meter.
Three-Phase Inverters
SolaX specifies the DTSU666-CT for use with its three-phase inverters. Single-phase SolaX systems use the single-phase DDSU666-CT, which is a separate product.
Important Safety Information
Installation must be carried out by authorised personnel and a qualified electrician to BS 7671. SolaX warns of danger of high voltage: cut off all power to the inverter before installation and wait 5 minutes after power-off. As with any 5A-secondary CT, do not leave the CT secondary open-circuit while current is flowing.
Three CTs Included
Supplied with three 200A/5A CTs (1m leads) for three-phase measurement.
Built-In Display
Read power, energy, voltage and current on the meter itself, without the SolaX app.
Import & Export Metering
Measures import, export and total power and energy for energy management with SolaX three-phase inverters.
RS485 Modbus-RTU
RS485 Modbus-RTU link to the inverter, with 9600bps as the default and 1200 to 19200bps selectable.
DIN-Rail Mounting
Fits a 35mm DIN rail in a four-module 72mm housing, for indoor installation.
Fuse-Free, Sealed Design
A fuse-free, fully sealed and naturally cooled construction for reliability.
Model
Type of CT
CTs In Pack
Width
CHINT DTSU666-CT (this product)
5A output (200A/5A)
3
72mm
SolaX M3-40
40mA output
Set of 3 (100A/40mA)
45mm
Electrical
Power grid type
3P4W / 3P3W
Nominal voltage
3 x 220/380V to 3 x 240/415V
Power supply input (phase voltage)
154 to 286Vac
Measurement range, phase voltage
168 to 312Vac
Measurement range, line voltage
290.5 to 539.5Vac
Current input via CT
0.015 to 1.5(6)A (CT: 200A)
Frequency
50 / 60Hz
Accuracy class
Class C (0.5S)
Current Transformers
CTs supplied
3 x 200A/5A
CT lead length
1m
Recommended system size
200A or below
Communication
Interface
RS485
Protocol
Modbus-RTU
Baud rate
9600bps default (1200, 2400, 4800, 9600 or 19200bps)
Meter RS485 terminals
24 and 25
Measured Values
Energy
Import and export kWh and kvarh
Power
Instantaneous kW, kvar and kVA
Other
Current, voltage, frequency and power factor
Mechanical & Environment
Dimensions (H x W x D)
100 x 72 x 65.5mm
Mounting
35mm DIN rail, indoor installation
Operating humidity
Below 75% (non-condensing)
Wiring
Voltage inputs (L1, L2, L3)
Meter ports 2, 5 and 8
Neutral (N)
Meter port 10
CT inputs
Meter ports 1, 3, 4, 6, 7 and 9
In the Pack
Contents
Meter, 3 x 200A/5A CTs, RS485 cable (10m) and RJ45 connector
What is the DTSU666-CT for?
It meters import, export and total power and energy at the grid connection of a three-phase system, so a SolaX three-phase inverter can manage energy. It also shows the readings on its own display.
What size of system is it for?
SolaX specifies it for systems of 200A or below, using the supplied 200A/5A CTs. For larger supplies use a meter and CTs rated for the current.
Can I use it with a single-phase inverter?
SolaX specifies the DTSU666-CT for three-phase inverters. For single-phase systems SolaX offers the DDSU666-CT, a separate single-phase meter.
How does it differ from the SolaX M3-40?
The DTSU666-CT is a CHINT meter with three 200A/5A CTs and a built-in display. The M3-40 is a SolaX meter that uses 40mA-output CTs. The two CT types are not interchangeable.
How does it connect to the inverter?
By RS485. The meter's RS485 terminals are 24 and 25, and an RJ45 connector is supplied for the inverter end. Follow the inverter manual, using matching wire colours at both ends.
Is it for indoor or outdoor use?
SolaX designs it for indoor installation, on a wall or in a distribution board on a 35mm DIN rail, so mount it indoors.
