CHINT DTSU666 Series User manual

DTSU666 series three phase four wire electronic energy meter
DSSU666 series three phase three wire electronic energy meter
User Manual
ZTY0.464.1448
Zhejiang Chint Instrument & Meter Co., Ltd.
Apr., 2022.

DTSU666 series and DSSU666 series
three phase electronic energy meter
ZTY0.464.1448
User manual
Page 1, Total 21
1. Brief Introduction
1.1 Main application & applicable range
DTSU666 series three phase four wire and DSSU666 series three phase three wire electronic
energy meter (din-rail) (hereinafter referred to as the “instrument”) is designed based on power
monitoring and energy metering demands for electric power system, communication industry,
construction industry, etc. as a new generation of intelligent instrument combining measurement and
communication function, mainly applied into the measurement and display for the electric parameters
in the electric circuit including three voltage, three current, active power, reactive power, frequency,
positive& negative energy, four-quadrant energy, etc. Adopting the standard DIN35mm din rail
mounting and modular design, it is characterized with small volume, easy installation and easy
networking, widely applied into the internal energy monitoring and assessment for industrial and
mining enterprises, hotels, schools, large public buildings.
Complied standards:
IEC 61010-1:2010《Safety requirements for electrical equipment for measurement，control and
laboratory use Part1:General requirements》
IEC 61326-1:2013 《Electrical equipment for measurement，control and laboratory use –EMC
requirements Part1:General requirements》
MODUS-RTU protocol.
1.2 Product Features
1) Characterized with positive and reverse active power, combined active power, combined
reactive power, four quadrant reactive power metering and storage function with combination
mode character can be set.
2) RS485 communication function with communication protocol complied with Modbus-RTU.
3) Adopting the standard DIN35mm din rail mounting and modular design, it is characterized
with small volume, easy installation and easy networking.
4) The update speed of active power is better than 120ms.

DTSU666 series and DSSU666 series
three phase electronic energy meter
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1.3 Product model
Table 1 product model and specification
Model
Reference
voltage
（V）
Current
specification
（A）
Impulse constant
Accuracy class
imp/kWh
imp/kvarh
DTSU666-CT
3×220/380V...
3×240/415V
0.015-1.5(6)A
6400
6400
active energy
EN 50470-3:Class C
DTSU666
0.25-5(80)A
400
400
active energy
EN 50470-3:Class B
DTSU666
3×230/400V
OR
3×220/380V
1.5(6)A
6400
6400
Active class
0.5S,reactive class 2
5(80)A
400
400
Active class 1.
Reactive class 2
DSSU666
3×400V
OR 3×380V
1.5(6)A
6400
6400
Active class
0.5S,reactive class 2
5(80)A
400
400
Active class 1.
Reactive class 2
DTSU666
3×277/480V
Customized
specifications
1.5(6)A
6400
6400
Active class
0.5S,reactive class 2
5(80)A
400
400
Active class 1.
Reactive class 2
DSSU666
3×480V
Customized
specifications
1.5(6)A
6400
6400
Active class
0.5S,reactive class 2
5(80)A
400
400
Active class 1.
Reactive class 2
Note1：0.015-1.5(6)A is Connection through current transformers,starting current is 0.015A;
Note2：0.25-5(80)A is direct access,starting current is 0.02A;
Note3：1.5 (6)A is connected through current transformer, 5 (80) A is directly connected. In order to
meet the requirements of different countries and regions, the specifications are slightly different,
subject to the actual object.
Note4：The above voltage specifications support 3×127/220V and 3×57.7/100V access.
Note5：Customized specification 3×277/480V are only suitable for specific occasions, the voltage of
line A must be above 100V. The maximum phase voltage does not exceed 310V(three-phase four-wire),

DTSU666 series and DSSU666 series
three phase electronic energy meter
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User manual
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and the maximum line voltage does not exceed 540V(three-phase three-wire),Suitable for specific
occasions
1.4 Model composition and meanings
Figure 1 Model composition and meanings
1.5 Applicable environmental condition
1.5.1 Temperature range
Indoor type:
Regulated working temperature range: -10℃～+45℃；
Limited working temperature range: -25℃～+75℃；
1.5.2 Relative humidity(Annually average):≤75％RH；
1.5.3 Atmospheric pressure: 63.0kPa～106.0kPa( altitude 4km and below), excepting the requirements
for special orders.
2. Working Principle
The instrument are composed of high accurately integrated circuit specially for measurement
(ASIC) and managing MCU, memory chip, RS485 communication module, etc.
The working principle block diagram of the instrument is shown in figure 2

DTSU666 series and DSSU666 series
three phase electronic energy meter
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Figure 2 Working principle block diagram
2.1.Principle for the main function module
2.1.1.Metering part
The special metering integrated circuit (ASIC) integrated six load two order ∑-△type of A/D
conversion, please take the digital signal processing measured by the voltage circuit as well as all the
power, energy, effective values, power factor and frequency. This metering chip can measure the active
power, reactive power, apparent power, active energy, reactive power, apparent energy of each phase
and combined phase, and at the same time measuring current, voltage effective values, power factor,
phase angle, frequency and other parameters, entirely satisfying the needs of power meter. The chip
provides an SPI interface, convenient for metering parameters as well as parameter calibration
between the management MCU.
2.1.2.Data processing part
Management MCU will timely read the electrical parameters such as current, voltage, power, etc.
in the metering chips, judging the current quadrant based on the read data, and judging the current

DTSU666 series and DSSU666 series
three phase electronic energy meter
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operated rate based on time and time rate, then adding the energy read from the metering chip to the
corresponding quadrant energy and total energy based on the rate and quadrant, at the same time,
calculating the corresponding combined energy based on the energy combination mode, and then store
and backup the energy.
The management MCU drives LCD module to display and exchange data with the outside through
RS485 communication interface.
3. Main Technical Performance & Parameters
3.1. limit of error caused by the current augment
Table 2 The limit value of the active percentage error of meters on balanced load
type
Range of current
Power factor
Percentage error limit of various grade
instruments（%）
0.5S
Class 1
Class 2
Access via
current
transformer
0.01In≤I＜0.05In
1
±1.0
±1.5
±2.0
0.05In≤I≤Imax
1
±0.5
±1.0
±1.2
0.02In≤I＜0.1In
0.5L、0.8C
±1.0
±1.5
±2.0
0.1In≤I≤Imax
0.5L、0.8C
±1.0
±1.0
±1.2
Direct access
instrument
0.05Ib≤I＜0.1Ib
1
-
±1.5
±2.0
0.1Ib≤I≤Imax
1
-
±1.0
±1.2
0.01Ib≤I＜0.2Ib
0.5L、0.8C
-
±1.5
±2.0
0.2Ib≤I≤Imax
0.5L、0.8C
-
±1.0
±1.2
Remark
In：secondary rated current of the current transformer; Ib：calibrated current of
the meter;
L:inductive；C：capacitive；
Table 3 The limit value of the reactive percentage error of meters on balanced load
Current value
sinφ
（inductive or
capacitive ）
Percentage error limit of various
grade instruments（%）
Direct access instrument
Access via
transformer
2
0.05Ib  I  0.1Ib
0.02In  I  0.05In
1
2.5

DTSU666 series and DSSU666 series
three phase electronic energy meter
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0.1Ib  I  Imax
0.05In  I  Imax
1
2.0
0.1Ib  I  0.2Ib
0.05In  I  0.1In
0.5
2.5
0.2Ib  I  Imax
0.1In  I  Imax
0.5
2.0
0.2Ib  I  Imax
0.1In  I  Imax
0.25
2.5
Table 4 The limit value of the active percentage error of meters on imbalanced load
Current value
Power factor
Percentage error limit of various grade
instruments（%）
Direct access
instrument
Access via
transformer
0.5S
Class 1
Class 2
0.1 Ib  I  Imax
0.05In  I  Imax
1
±0.6
±2.0
±3.0
0.2Ib  I  Imax
0.1In  I  Imax
0.5L
±1.0
±2.0
±3.0
Table 5 The limit value of the reactive percentage error of meters on imbalanced load
Current value
Current value
Percentage error limit of various
grade instruments（%）
Direct access
instrument
Direct access
instrument
Class 2
0.1 Ib  I  Imax
0.05In  I  Imax
1
±3.0
0.2Ib  I  Imax
0.1In  I  Imax
0.5
±3.0
3.2. Start
Under the power factor of 1.0 and started current, the instrument can be started and continuously
measure (for multiple phase instrument, it will bring balanced load). If the instrument is designed
based on measurement for dual directional energy, then it is applicable for each direction of energy.
Table 6 start current
instrument
Instrument rating
Power factor
0.5S
1
2
Direct access instrument
-
0.004Ib
0.005Ib
1
Access via CT
0.001Ib
0.002Ib
0.003Ib
1
3.3. Defluction
When adding voltage while there is no current on the current circuit, the test output of the
instrument shall not produce another pulse. When testing, the current circuit shall be opened, and the

DTSU666 series and DSSU666 series
three phase electronic energy meter
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User manual
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added voltage for voltage circuit shall be 115% of the referenced voltage.
Shortest testing time
Δt
：
For instrument of class 0.5S and class1：
6
max
600 10
Δt [mi n]
n
k m U I

  
For instrument of class 2：
6
max
480 10
Δt [mi n]
n
k m U I

  
From the formula, k represents meter constant (imp/kWh), m represents measuring components,
Un represents referenced voltage (V) and Imax represents the maximized current (A).
3.4.Electrical parameters
Table 7 Electrical parameters
Specified operating voltage range
0.9Un～1.1Un
Extended operating voltage range
0.8Un～1.15Un
Ultimate operating voltage range
0 Un～1.15Un
Power consumption of the voltage
circuit
≤1.5W and 6VA
Power consumption of the current
circuit
Ib＜10A
≤0.2VA
Ib≥10A
≤0.4VA
Data save time after power off
≥10 years
4.Key components adoption
Table 8 Key components adoption
Model
DTSU666
Metering chip
HT7036
Crystal
oscillator
5.5296MHz，32.768kHz
Printed PCB
ZTY8.067.2267，ZTY8.067.2837，ZTY8.067.2288
Power
transformer
EE19-0.9mH-B
Current
HLX1

DTSU666 series and DSSU666 series
three phase electronic energy meter
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5.Main function
5.1.Displayed function
From the displayed interface, the electrical parameter and energy data are all primary side data
(that is, the multiplied by current and voltage ratios). The energy measuring value will be displayed
seven bits, with the displaying range from 0.00kWh to 9999999MWh.
Figure 3 Liquid crystal display
Table 9 Display interface
No.
Display interface
Instruction
No.
Display interface
Instruction
1
Combined
active energy
=10000.00kWh
11
Phase C
current
=5.002A
2
Forward active
energy
=10000.00kWh
12
Combined
phase active
power
=3.291kW
3
Reserve active
energy
=2345.67kWh
13
Phase A
active power
=1.090kW
4
Protocol:
ModBus-RTU;
address =001
Baudrate=9600
None parity, 1
stop bits
14
Phase B
active power
=1.101kW
5
15
Phase C
active power
=1.100kW
transformer

DTSU666 series and DSSU666 series
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6
Phase A
voltage
=220.0V
16
Combined
phase power
factor
PFt=0.500
7
Phase B
voltage
=220.1V
17
Phase A
power factor
PFa=1.000
8
Phase C
voltage
=220.2V
18
Phase B
power factor
PFb=0.500
9
Phase A
current
=5.000A
19
Phase C
power factor
PFc=-0.500
10
Phase B
current
=5.001A
NOTE1：The factory default baud rate is 9600bps,n.8.1;The communication address of Modbus
protocol is 01 (1 ~ 247), E1 means even check 1 stop bit, O1 means odd check 1 stop bit Two stop bits,
N2 means two stop bits without check;
NOTE2：The above interface is used to show the meaning of the display content. Due to the
different functions of the instrument, the display symbols will increase or decrease.
NOTE3：When RS485 communicating, the telephone sign will flashes.
5.2.Programming function
5.2.1.Programming parameter
Table 10 Programming parameter
Parameter
Value range
Instruction
1～9999
Current ratio, used for setting the input loop current ratio:
When the current is connected to the line via the
transformer, Ct=the rated current of the primary loop / the
rated current of the secondary circuit;

DTSU666 series and DSSU666 series
three phase electronic energy meter
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When the current is directly connected to the line, Ct shall
be set as 1.
0.1～999.9
Voltage ratio, used for setting the voltage ratio of the input
loop;
When the voltage is connected to the line via the
transformer, Pt= the rated voltage of the primary loop / the
rated voltage of the secondary circuit;
When the voltage is directly connected to the line, Pt shall
be set as 1.0.
1：645;
2：n.2;
3：n.1;
4：E.1;
5：O.1;
Communication protocol switches:
1：Dl/T 645-2007；
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;
0：1200；
1：2400；
2：4800；
3：9600；
4: 19200;
Communication baud rate:
0：Communication baud rate to be 1200bps；
1：Communication baud rate to be 2400bps；
2：Communication baud rate is 4800bps；
3：Communication baud rate is 9600bps；
4：Communication baud rate is 19200bps；
1～247
Communication address
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.
0:n0；1:E
The setting is 1, representing the allowed instrument energy
data clearance, which will be zero reset after clearing.
0:P；1:Q；
Pulse output:

DTSU666 series and DSSU666 series
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2:S；
0：active energy pulse; 1: reactive energy pulse; 2：Others.
0～30
Display in turns(second)
0：Timely display；
1～30：Time interval of actual display.
0～30
Backlight lighting time control（minutes）
0：Normally light；
1～30：backlight lighting time without button operation
5.2.2.Programming operation
Button description: “SET” button represents “confirmation”, or “cursor shift” (when input digits),
“ESC” button represents “exit”, “→” (“ ”) button represents “add”. The input code is (default
701).
Figure 4 Setting examples for current ratio

DTSU666 series and DSSU666 series
three phase electronic energy meter
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Figure 5 Setting examples for communication address and Baud Rate
5.3. Communication function
Characterized with a RS485 communication interface, the baud rate can be changed between
1200bps, 2400bps, 4800bps , 9600bps and 19200. The default baud rate is 9600bps, with the
calibration bit and stop bit to be N.1, and instrument address 01 (please see instrument factory number
or crystal display screen).
Communication protocol: complied with the requirement of Modbus communication protocol.
The following table is the common ModBus protocol address table. ModBus_RTU protocol read
command is 03H, write command is 10H.
Table 11 ModBus protocol address table
Parameter
address
Parameter
code
Instructions of parameters
Data type
Data
length
Word
Read
Write
Keyboard parameters (specific parameters see the instructions of programming parameters, the actual value
with (*) parameter＝communication parameter value × 0.1）
0000H
REV.
Software Version
Signed
1
R
0001H
UCode
Programming code codE(1～9999)
Signed
1
R/W
0003H
net
Network selection (0:three phase four
wire,1:three phase three wire)
Signed
1
R/W
0006H
IrAt
Current transformer rate IrAt(1～9999)
Signed
1
R/W
0007H
UrAt
Voltage transformer rate UrAt（*）
(1～9999 represents voltage ratio 0.1～999.9)
Signed
1
R/W
000AH
Disp
Rotating display time（s）
Signed
1
R/W
000BH
B.LCD
Backlight time control（m）
Signed
1
R/W
000CH
Endian
Reserve
Signed
1
R/W
002CH
Protocol
Protocol switching
(1:DL/T645;2:n.2;3:n.1;4:E.1;5:o.1)
Signed
1
R/W
002DH
bAud
Communication baud rate bAud
(0:1200;1:2400;2:4800;3:9600;4:19200)
Signed
1
R/W
002EH
Addr
Communication address Addr(1～247)
Signed
1
R/W

DTSU666 series and DSSU666 series
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Electricity data on the secondary side
2000H
Uab
Three phase line voltage data, Unit V(×0.1V)
float
2
R
2002H
Ubc
float
2
R
2004H
Uca
float
2
R
2006H
Ua
Three phase voltage data, Unit V(×0.1V)
(Invalid for three phase three wire)
float
2
R
2008H
Ub
float
2
R
200AH
Uc
float
2
R
200CH
Ia
Three phase current data, Unit A(×0.001A)
float
2
R
200EH
Ib
float
2
R
2010H
Ic
float
2
R
2012H
Pt
Combined active power, Unit W(×0.1W)
float
2
R
2014H
Pa
A phase active power, Unit W(×0.1W)
float
2
R
2016H
Pb
B phase active power, Unit W(×0.1W)
(Invalid for three phase three wire)
float
2
R
2018H
Pc
C phase active power, Unit W(×0.1W)
float
2
R
201AH
Qt
Combined reactive power, Unit var(×0.1var)
float
2
R
201CH
Qa
A phase reactive power, Unit var(×0.1var)
float
2
R
201EH
Qb
B phase reactive power, Unit var(×0.1var)
(Invalid for three phase three wire)
float
2
R
2020H
Qc
C phase reactive power, Unit var(×0.1var)
float
2
R
202AH
PFt
Combined power factor(forward number：
inductive，reverse number：capacitive) (×0.001)
float
2
R
202CH
PFa
A phase power factor(forward number：
inductive，reverse number：capacitive)
(Invalid for three phase three wire) (×0.001)
float
2
R
202EH
PFb
B phase power factor(forward number：
inductive，reverse number：capacitive)
(Invalid for three phase three wire) (×0.001)
float
2
R
2030H
PFc
C phase power factor(forward number：
inductive，reverse number：capacitive)
(Invalid for three phase three wire) (×0.001)
float
2
R
2044H
Freq
Frequency, Unit Hz(×0.01Hz)
float
2
R
Power secondary side data
101EH
ImpEp
（current）Total Forward active energy(kWh)
float
2
R

DTSU666 series and DSSU666 series
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1020H
ImpEpA
（current）A Forward active energy(kWh)
float
2
R
1022H
ImpEpB
（current）B Forward active energy(kWh)
float
2
R
1024H
ImpEpC
（current）C Forward active energy(kWh)
float
2
R
1026H
NetImpEp
（current）Net Forward active energy(kWh)
float
2
R
1028H
ExpEp
（current）Total Reverse active energy(kWh)
float
2
R
102AH
ExpEpA
（current）A Reverse active energy(kWh)
float
2
R
102CH
ExpEpB
（current）B Reverse active energy(kWh)
float
2
R
102EH
ExpEpC
（current）C Reverse active energy(kWh)
float
2
R
1030H
NetExpEp
（current）Net Reverse active energy(kWh)
float
2
R
Note 1：When the ratio of the voltage transformer is 1, the data of read voltage transformer ratio
register UrAt is 10. When the ratio of voltage transformer is 1, ignore the above
table(UrAt×0.1).
Note 2：Single-precision floating point adopts standard IEEE754 format, total 32 bit(4 word). The
single-precision floating point mode is assumed to be ABCD(high type in the front, low byte
behind).
Note 3: The table only give the regular correspondence address. If you need the primary data address
and other addresses, you can call for the detailed communication protocol.
5.4. Energy measurement function
The horizontal axis of the measurement plane represents the current vector I (fixed on the
horizontal axis), and the instantaneous voltage vector is used to represent the current power
transmission. Compared with the current vector I, it has phase angleφ.
The counter-clockwise direction φangle is positive. A schematic diagram of the four-quadrant is
shown in Figure 6

DTSU666 series and DSSU666 series
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Figure 6 Measurement schematic diagram for energy four quadrants
6. Outline and installation size
Table 12 Installation size
Model
modulus
Outline size (length×
width× height) mm
Installation size
(din rail)
Weight
(g)
DTSU666
4
100×72×65.5
DIN35 Standard
din rail
440
DSSU666
4
440
DTSU666-CT
4
440
Figure 7 Access via CT Outline size diagram (four modulus)

DTSU666 series and DSSU666 series
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Figure 8 Direct access instrument Outline size diagram (four modulus)
Note 1: The undeclared tolerance is ± 1 mm;
Note 2: Only indicates the size, and the shape of different specifications is slightly different.
Figure 9 current cable terminal (Conductor Cross-sectional Area Range ≤16 mm2)
Figure 10 RS485 cable terminal (Conductor Cross-sectional Area Range 0.25-1mm2 )
7. Installation and operation manual
7.1. Inspection Tips
When unpacking the carton, if the shell has obvious signs caused by severe impact or falling,
please contact with the supplier as soon as possible.

DTSU666 series and DSSU666 series
three phase electronic energy meter
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After the instrument being removed from the packing box, it should be placed on a flat and safe
plane, facing up, not overlaying for more than five layers. If not installed or used in a short time, the
electric meter shall be packed and placed to the original packing box for storage.
7.2. Installation and tips
7.2.1. Installation and Inspection
If the model No or configuration in the original packing box is not in accordance with the
requirement, please contact with the supplier. While, if the inner package or shell has been damaged
after removing the instrument from the packing box, please do not install, power on the instrument,
please contact with the supplier as soon as possible, instead.
7.2.2.Installation
It requires experienced electrician or professional personnel to install it and you must read this
operation manual. During the installation, if the shell has obvious damage or marks caused by violent
impact or falling, please do not install it or power on and contact with the supplier as soon as possible.
Figure 11 Installation Diagram
7.3.Typical wiring
Three phase four wire: direct connect Three phase three wire: direct connect

DTSU666 series and DSSU666 series
three phase electronic energy meter
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Figure 12 Figure 13
Three phase four wire: via current transformer Three phase three wire: via current transformer
Figure 14 Figure 15
RS485 Pulse output
Figure 16 Figure 17
◆Voltage signal (only for connection via current transformer)
2-------UA(Phase A voltage input terminal) 5 -------UB (Phase B voltage input terminal)
8-------UC (Phase C voltage input terminal) 10------UN (Phase N voltage input terminal)
◆Current signal:
1-------IA*(Phase A current input terminal) 3------IA (Phase A current output terminal)
4-------IB*(Phase B current input terminal) 6------IB (Phase B current output terminal)
7-------IC*( Phase C current input terminal) 9------IC(Phase C current output terminal)
◆RS485 Communication wire
24-------A（RS485 Terminal A）25-------B（RS485 Terminal B）
◆Auxiliary function
19------ Active energy and reactive energy output high terminal
21------ Active energy and reactive energy output low terminal
NOTICE:In the Figure 12、13、14、15，the L1、L2、L3 correspond to PhaseA、Phase B、Phase C
8.Diagnosis, analysis and elimination for common faults
Fault phenomenon
Reason analysis
Elimination
Notes

DTSU666 series and DSSU666 series
three phase electronic energy meter
ZTY0.464.1448
User manual
Page 19, Total 21
No display when
powered on
1. Incorrect wiring
2. Abnormal voltage for
the instrument
1. If it is wrongly connected,
please reconnect based on the
right wiring mode (see the
wiring diagram).
2. If the supplied voltage is
abnormal, please choose the
specified voltage.
3. If not the above problems,
please contact with the local
supplier.
Abnormal RS485
communication
1. RS485
communication cable
is opened, short
circuit or reversely
connected.
2. Address, baud rate,
data bit and check bit
is not in accordance
with the host
computer.
3. The end of RS485
communication cable
has not been matched
with resistance (when
the distance over than
150 meters)
4. Not matched with the
communication
protocol order of the
host computer
1. If there is any problem with the
communication cable, please
change it.
2. Set the address, baud rate, data
bit and check bit through
buttons and confirm it is the
same with the host computer,
then set the operation to be
“parameter settings”.
3. If the communication distance
is over than 150 meters, and the
communication parameter
settings are the same as the host
computer, but cannot be
communicated, then please
lower the baud rate or add a
resistance of 120Ωat the start
terminal and ending terminal.
Abnormal data for the
electrical parameter
(voltage, current, power,
etc.)
1. The transformer's
ratio hasn’t been set,
and the instrument
displays the
secondary side data.
1. If setting the transformer ratio,
please set the voltage ratio and
current ratio based on “parameter
setting”
2. If wrongly connected, please