Eastron SDM72CT-M User manual

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
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 Measures kWh, kVArh, W, Var, VA, PF, Hz, V, A etc.
Bi-directional measurement IMP & EXP
Two pulse outputs
RS485 Modbus
Din rail mounting 35mm
1/5A CT connection
Better than Class 1/ B accuracy
SDM72CT-M
Three Phase Four Wire Energy Meter
User Manual V1.0
2018

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 2 -
Introduction
The SDM72CT-M is digital three phase 4 wire energy meter with a white back-lighted LCD screen for perfect
reading. The unit measures and displays the characteristics of three phase four wires(3p4w) supply, including
voltage, frequency, current, power ,active and reactive energy, imported or exported. Energy is measured in terms
of kWh, kVArh. The requisite current input(s) are obtained via current transformers(CT).
This meter can be configured to work with a wide range of CTs, giving the unit a wide range of operation. Built-in
interfaces provides pulse and RS485 Modbus RTU outputs. Configuration is password protected
PART 1 Specification
General Specifications
Voltage AC (Un) 3x230(400)V
Voltage Range 80~120% Un
Base Current (Ib) 5A CT input
Max. Current (Imax) 120% of Ib AC
Mini Current (Imin) 5% of Ib AC
Starting current 0.4% of Ib
Power consumption <2W/10VA
Frequency 50/60Hz
AC voltage withstand 4KV for 1 minute
Impulse voltage withstand 6KV-1.2uS wavform
Overcurrent withstand 20Imax for 0.5s
Pulse output rate Configurable ( Pulse 1)
1000imp/kWh (Pulse 2)
Display LCD with backlit
Max. Reading 9999999kWh
Active energy Class 1 IEC62053-21
Class B EN50470-3
Unit Characteristics
The Unit can measure and display:
Line voltage of all phases
Frequency
Line Currents of all phases
Power and power factor
Active energy imported and exported
Reactive energy imported and exported

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 3 -
Two pulse output indicates real-time energy measurement. An RS485 output allows remote monitoring from
another display or a computer.
Current Transformer Primary Current
The unit can be configured to operate with CT ratio between primary current and secondary current. The
secondary CT has two options: 1A/5A
RS485 Serial –Modbus RTU
This unit uses an RS485 serial port with Modbus RTU protocol to provide a means of remotely monitoring and
controlling the Unit
Set-up screens are provided for setting up the RS485 port.
Pulse output
The unit provides two pulse outputs. Both pulse outputs are passive type.
Pulse output 1 is configurable. The pulse output can be set with Modbus protocol:
0.01 kWh / imp
0.1 kWh / imp
1 kWh /imp
10 kWh / imp
100 kWh /imp
1000=1000 kWh/kVArh
Pulse width: 200/100(default)/60ms can set with Modbus protocol.
Pulse output 2 is non-configurable. It is fixed up with total kWh. The constant is 1000imp/kWh.
RS485 Output for Modbus RTU
For Modbus RTU, the following RS485 communication parameters can be configured from the Set-up menu:
Baud rate 1200,2400, 4800, 9600
Parity none (default)/odd/even
Stop bits 1 or 2
RS485 network address nnn – 3-digit number, 001 to 247
Modbus™ Word order Hi/Lo byte order is set automatically to normal or reverse. It cannot be configured
from the set-up menu.
Environment
Operating temperature -25℃to +55℃
Storage and transportation temperature -40℃to +70℃
Reference temperature 23℃±2℃
Relative humidity 0 to 95%, non-condensing
Altitude up to 2000m
Warm up time 10s
Installation category CAT III
Mechanical Environment M1
Electromagnetic environment E2

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
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Degree of pollution 2
Mechanics
Din rail dimensions 72x100x66 (WxHxD) DIN 43880
Mounting DIN rail 35mm
Sealing IP51 (indoor)
Material self-extinguishing UL94V-0
PART 2 Operation
Initialization Display
When it is powered on, the meter will initialize and do self-checking.
Full Screen
Software Version
Total active energy(kWh)
Total=Import+ Export
Max read: 9999999 kWh
Buttons function
There are two buttons on the front panel.
>Scroll the display for data checking.
>Changing option at Set-up mode
>Exit the Set-up mode

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 5 -
Scroll display
>Set-up mode entry
>Confirmation
After initialization and self-checking program, the meter display the measured values. The default page is total
kWh. If the user wants to check other information, please press the scroll button on the front panel.
Total active energy(kWh)
Total=Import+ Export
import energy
export energy
Total reactive energy (kVArh)
Imp reactive energy
Exp reactive energy

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
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Voltage L1
Voltage L2
Voltage L3
Current L1
Current L2
Current L3
Total active power (W)
Active power L1

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 7 -
Active power L2
Active power L3
Total reactive power (VAr)
Reactive power L1
Reactive power L2
Reactive power L3
Total apparent power ( VA)
Apparent power L1

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 8 -
Apparent power L2
Apparent power L3
Total Power Factor
Power Factor L1
Power Factor L2
Power Factor L3
Frequency
CT ratio

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 9 -
Pulse Constant
Modbus Address
Baud Rate
Parity
Set-up Mode
To get into Set-up Mode, the user need press the “Enter” button for 3 second.
Page
Display
Descriptions
1 Password
To get into Set-
up mode, it asks a password
confirmation. Default password: 1000
Use and to enter correct password.
The entering information is wrong. The operation fails.
2
Keep pressing for 3 second, the current selection
will flash, use and to change the Modbus
address. Options: 1~247

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 10
Keep press for 3s to confirm the selection.
3
Keep pressing for 3 second, the current selection
will flash, use and to change the Baud rate.
Options: 1.2k, 2.4k,4.8k,9.6k ( default )
Keep press for 3s to confirm the selection.
4
Keep pressing for 3 second, the current selection
will flash, use and
to change the Parity.
Options: EVEN,ODD,NONE ( default )
Keep press for 3s to confirm the selection.
5
Use to select the CT ratio option. Keep pressing
for 3 second, the current selection will flash, use
and
to enter the CT Ratio. The range is
from 0001 to 2000. For example, if using a 100A/5A
current transformer, you shall enter 0020.
Keep press for 3s to confirm the selection.
5-1
6
Use to select the Password option. Keep
pressing for 3 second, the current selection will
flash, use and
to enter the new
password. The range is from 0001 to 9999.
Keep press for 3s to confirm the selection.
6-1
Keep pressing button to exit the set-up mold.

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 11
Wiring diagram
Dimensions

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 12
Input Registers
PART 3 Modbus Protocol
Input registers are used to indicate the present values of the measured and calculated electrical quantities. Each
parameter is held in two consecutive 16 big register. The following table details the 3X register address, and the
values of the the address bytes within the message. A (*) in the column indicated the parameter is valid for the
particular wiring system, Any parameter with a cross (X) will return the value zero. Each parameter is held in the
3X registers. Modbus Protocol function code 04 is used to access all parameters.
For example, to request: Amps 1 Start address = 0006
No.of registers = 0002
Amps 2 Start address = 0008
No. Of register = 0002
Each request for data must be restricted to 30 parameters or less. Exceeding the 30 parameter limit will cause a
Modbus Protocol exception code to be returned.
Address
(Register)
Input Register Parameter
Modbus
Protocol Start
Address Hex
3
Ø
3
Ø
1
Ø
Description
Length
(bytes)
Data
Format
Units
Hi
Byte
Lo
Byte
4
W
3
W
2
W
30001 Phase 1 line to neutral volts. 4 Float V 00 00 √X √
30003 Phase 2 line to neutral volts. 4 Float V 00 02 √X X
30005 Phase 3 line to neutral volts. 4 Float V 00 04 √X X
30007 Phase 1 current. 4 Float A 00 06 √√√
30009 Phase 2 current. 4 Float A 00 08 √√X
30011 Phase 3 current. 4 Float A 00 0A √√X
30013 Phase 1 active power. 4 Float W 00 0C √X √
30015 Phase 2 active power. 4 Float W 00 0E √X X
30017 Phase 3 active power. 4 Float W 00 10 √X X
30019 Phase 1 apparent power. 4 Float VA 00 12 √X √
30021 Phase 2 apparent power. 4 Float VA 00 14 √X X
30023 Phase 3 apparent power. 4 Float VA 00 16 √X X
30025 Phase 1 reactive power. 4 Float VAr 00 18 √X √
30027 Phase 2 reactive power. 4 Float VAr 00 1A √X X
30029 Phase 3 reactive power. 4 Float VAr 00 1C √X X
30031 Phase 1 power factor (1). 4 Float None 00 1E √X √
30033 Phase 2 power factor (1). 4 Float None 00 20 √X X
30035 Phase 3 power factor (1). 4 Float None 00 22 √X X
30043 Average line to neutral volts. 4 Float V 00 2A √X X
30047 Average line current. 4 Float A 00 2E √√√
30049 Sum of line currents. 4 Float A 00 30 √√√

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
- 13
Holding Registers
30053 Total system power. 4 Float W 00 34 √√√
30057 Total system volt amps. 4 Float VA 00 38 √√√
30061 Total system VAr. 4 Float VAr 00 3C √√√
30063 Total system power factor (1). 4 Float None 00 3E √√√
30071 Frequency of supply voltages. 4 Float Hz 00 46 √√√
30073 Import Wh since last reset . 4 Float kWh 00 48 √√√
30075 Export Wh since last reset . 4 Float kWH 00 4A √√√
30077 Import VArh since last reset . 4 Float kVArh 00 4C √√√
30079 Export VArh since last reset . 4 Float kVArh 00 4E √√√
30201 Line 1 to Line 2 volts. 4 Float V 00 C8 √√X
30203 Line 2 to Line 3 volts. 4 Float V 00 CA √√X
30205 Line 3 to Line 1 volts. 4 Float V 00 CC √√X
30207 Average line to line volts. 4 Float V 00 CE √√X
30225 Neutral current. 4 Float A 00 E0 √X X
30343 Total kwh (3) 4 Float kWh 01 56 √√√
30345 Total kvarh (3) 4 Float kVArh 01 58 √√√
Notes:
1. The power factor has its sign adjusted to indicate the direction of the current. Positive refers to forward current,
negative refers to reverse current.
2. The power sum demand calculation is for import –export.
3. Total kWh / kVarh equals to Import + export.
Holding register are used to store and display instrument configuration settings. All holding registers not listed
in the table below should be considered as reserved for manufacturer use and no attempt should be made to
modify their values.
The holding register parameters may be viewed or changed using the Modbus Protocol. Each parameter is
held in two consecutive 4X registers. Modbus Protocol Function Code 03 is used to read the parameter and
Function code 10 is used to write. Write only to one parameter per massage.
Address
Register
Parameter
Number
Parameter
Modbus Protocol
Start Address Hex
Valid range
Mode
High Byte Low Byte
40013 7 Pulse 1 Width 00 OC
Write pulse on period in
milliseconds: 60, 100 or 200, default 200.
Length : 4 byte
Data Format : Float
r/w
40015 8
Access authority
(write password to
00 0E
Read: to get status of the current access.
0: failed to get the access
r/w

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
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get the access and
read the status of the
access)
(KPPA)
1 : already got the access
Write: write correct password to get the
access
Length : 4 byte
Data Format : Float
40019 10 Parity / Stop 00 12
Write the network port parity/stop bits for
MODBUS Protocol, where: 0 = One stop bit
and no parity, default. 1 = One stop bit and
even parity. 2 = One stop bit and odd parity.3
= Two stop bits and no parity.
Length : 4 byte
Data Format : Float
r/w
40021 11 Modbus Address 00 14
Write the network port node
address: 1 to 247 for MODBUS Protocol,
default 1.
Length : 4 byte
Data Format : Float
r/w
40023 12 Pulse 1 Rate 00 16
Write pulse rate index: n
= 1 to 5
1--0.01kwh/imp
2--0.1kwh/imp
3--1kwh/imp
4-10kwh/imp
5-100kwh/imp
Length : 4 byte
Data Format : Float
r/w
40025 13 Password 00 18
Read：get password
Write：change password
Length : 4 byte
Data Format : Float
r/w
40029 15 Network Baud Rate 00 1C
Write the network port baud rate for
MODBUS Protocol, where:
0 = 2400 baud. 1 = 4800 baud.
2 = 9600 baud ( default).
5 = 1200 band
Length : 4 byte
Data Format : Float
r/w
40033 17 CT ratio 00 20
CT ratio ( Range: 0001－2000)
Default: 1
Length : 4 byte
Data Format : Float
(KPPA is asked)
r/w
40059 30 Time for scrolling 00 3A Default: 0, Unit: s r/w

Eastron SDM72CT-M User Manual
Zhejiang Eastron Electronic Co.,Ltd. Tel: [phone] 83698882 Fax: [phone]
Address: No.1369 Chengnan Road, Jiaxing, Zhejiang, 314001, China. Web: www.eastron.com.cn Email: [e-mail]
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display Range: 0~30, ( 0 means close scrolling)
Length : 4 byte
Data Format : Float
40061 31 Time of back light 00 3C
Default: 0. Unit: min
Rang :0~120. ( 0 means the back light will
work all the time )
Length : 4byte
Data Format : Float
r/w
40087 44 Pulse 1 Energy Type 00 56
Write MODBUS Protocol
input parameter for pulse
output 1：
1: import active energy
2: total active energy
4: export active energy, default
5: import reactive energy
6: total reactive energy
8: export reactive energy
Length : 4 byte
Data Format : Float
r/w
464513 32257 Serial Number FC 00
Serial number
Length : 4 byte
Data Format : unsigned int32
Note: Only read
ro