Ebyte E851-RTU User manual

E851-RTU(4440-ETH) User Manual

Chengdu Ebyte Electronic Technology Co.,Ltd E851-RTU(4440-ETH) User Manual
Copyright ©2012–2019, Chengdu Ebyte Electronic Technology Co.,Ltd
1
Contents
1. Quick Start................................................................................................................................................................................................3
1.1. Port connection..............................................................................................................................................................................3
1.1.1. RS485 connection...............................................................................................................................................................3
1.1.2. Switch Input Connection.................................................................................................................................................... 4
1.1.3. Relay output connection..................................................................................................................................................... 4
1.1.4. Differential analog input connection..................................................................................................................................4
1.2. Quick Use...................................................................................................................................................................................... 5
2. Product Introduction.................................................................................................................................................................................7
2.1. Basic parameters............................................................................................................................................................................7
2.2. Size, interface description............................................................................................................................................................. 8
2.3. Reload touch button description..................................................................................................................................................11
3. Modbus...................................................................................................................................................................................................11
3.1. Modbus address table.................................................................................................................................................................. 11
3.2. Modbus Address Table................................................................................................................................................................ 12
3.3. RS485 Serial Port Baud Rate Code Table................................................................................................................................... 13
4. Product Function.................................................................................................................................................................................... 14
4.1. Working mode............................................................................................................................................................................. 14
4.1.1.Slave mode........................................................................................................................................................................ 14
4.1.2. Host mode........................................................................................................................................................................ 15
4.2. Basic functions of IO...................................................................................................................................................................16
4.2.1. Switch DO Output............................................................................................................................................................16
4.2.2. Read switch DI input........................................................................................................................................................18
4.2.3. Read analog AI input........................................................................................................................................................19
4.2.4. Analog AI range setting....................................................................................................................................................21
4.3. IO Feature Function.................................................................................................................................................................... 21
4.3.1.Pulse count and count clear...............................................................................................................................................21
4.3.2. Switching input DI is automatically reported.................................................................................................................. 22
4.3.3. DO Time Settings for Switch Output............................................................................................................................... 23
4.4 Network related functions............................................................................................................................................................ 24
4.4.2. Custom registration package............................................................................................................................................ 25
4.4.3. Heartbeat package............................................................................................................................................................ 27
4.4.4. Heartbeat packet time.......................................................................................................................................................28
4.4.5. Heartbeat packet mode..................................................................................................................................................... 29
4.4.6. IP parameter setting of local WAN port........................................................................................................................... 30
4.4.7. DNS settings.....................................................................................................................................................................31
4.4.8. Ebyte Cloud Transparent Transmission............................................................................................................................32
4.4.9. Clear cache....................................................................................................................................................................... 32
4.4.10. Keep alive connection.................................................................................................................................................... 32
4.4.11. Timeout restart................................................................................................................................................................33
4.4.12. SOCKET Local Port Settings.........................................................................................................................................33
Important statement....................................................................................................................................................................................34
Revision History.........................................................................................................................................................................................34

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Features
Support 4 differential analog inputs, default current detection;
Supports 4-way digital input, dry contact as default ;
Support 4-way relay output;
Support socket connection to remote server, support TCP Client;
Data processing using Modbus TCP/RTU protocol;
Support connection to Ebyte cloud, command control;
Support two working modes, host mode, slave mode, slave can connect to multiple devices through RS485;
Support reload touch button, long press 5s, Modbus device address, RS485 serial baud rate and check digit to
restore factory settings;
Hardware watchdog with high reliability;
Multiple indicator lights show working status.
The power supply has good functions of over-current, over-voltage and anti-backconnection.
Note: Customization functions are available, such as conditional control (how to output based on input state)

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1. Quick Start
This chapter is a quick introduction to E851-RTU (4440-ETH) series products. It is recommended that users read this
chapter systematically and operate it according to the instructions. It will have a systematic understanding of the module
products. Users can also choose the chapters you are interested in to read according to their needs. For specific details
and instructions, please refer to the following chapters.
1.1. Port connection
1.1.1. RS485 connection
Note: When the 485 bus high frequency signal is transmitted, the signal wavelength is shorter than the transmission line.
The reflected wave will form at the terminal of the transmission line and interfere with the original signal. Therefore,
terminal resistance should be added at the end of the transmission line so that the signal will not reflect when it reaches
the end of the transmission line. The terminal resistance should be the same as the impedance of the communication
cable with a typical value of 120 ohms. Its function is to match the bus impedance and improve the anti-interference and
reliability of data communication.

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1.1.2. Switch Input Connection
1.1.3. Relay output connection
1.1.4. Differential analog input connection

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1.2. Quick Use
Wiring: Computer connects to E851-RTU (4440-ETH) via USB to RS485
Networking: Plug the network cable into the RJ45 port
Power supply: E851-RTU (4440-ETH) working voltage is DC 8~28V
1.2.1. RS485 Bus Control
Select the appropriate port and click “Search” to search for the device.
After searching for the device, click “Stop”.

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At this time, the device address of the current device can be seen, and the "auto refresh" processing can be performed,
and the switch output control, the digital input read, and the differential analog input can be read.

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1.2.2. Network control
Input http://yun.cdebyte.com/www/data_direct,The acquisition can be controlled by command, which adopts Modbus
TCP/RTU protocol.
2. Product Introduction
E851-RTU (4440-ETH) is a network IO product that supports 4-way digital input (default trunk connection), 4-way
differential analog input and 4-way relay output. Support Modbus TCP/RTU protocol. The product is highly user-friendly,
and users can easily and quickly integrate into their own systems to achieve remote control based on Ethernet.
2.1. Basic parameters
Name
Value
Hardware parameters
Product size(H*W*D)
172*107*29mm
Product weight
457.5±5g
Working temperature
-20℃~+70℃
Storage temperature
-40℃~+85℃
Working humidity
5%~95%
Storage humidity
1%~95%
Working voltage
8V~28V
Current acquisition range
0mA~20mA
Precision
0.2%
Data interface
RS485：1200~115200bps

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Software parameters
Network Type
Ethernet
Configuration command
Modbus TCP/RTU
Network protocol
Modbus TCP/RTU
Working mode
Host mode、Slave mode
Data transmission mode
TCP Client
2.2. Size, interface description

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SN
Ports
Function
Illustration
1
DC-IN transposon
DC socket 5.5*2.1mm
Power input，DC 8V~28V, 12V/24V is recommended,cannot
be powered with the crimp terminal at the same time
2
DC-IN +
Crimped power input positive
power input,DC 8V~28V，12V/24V is recommended,cannot
be powered with the DC socket at the same time
3
DC-IN -
Crimped power input negative
Power reference ground
4
RS485 B
RS485 interface B
RS485 interface B is connected with device B interface
5
RS485 A
RS485 interface A
RS485 interface A is connected with device A interface
6
RS485 G
Signal reference
can be unconnected
7
DIG
Switching input
Can be used in pairs with DI 4
8
DI 4
Switch input channel 4
Form dry contact with DIG
9
DIG
Switching input
Can be used in pairs with DI 3
10
DI 3
Switch Input Channel 3
Form dry contact with DIG
11
DIG
Switching input
Can be used in pairs with DI 2
12
DI 2
Switch Input Channel 2
Form dry contact with DIG
13
DIG
Switching input
Can be used in pairs with DI 1
14
DI 1
Switch Input Channel 1
Form dry contact with DIG
15
AIG
Differential analogue input
Can be used in pairs with AI 4
16
AI 4
Differential analog input channel 4
Differential analog input pin, forming input with AIG

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17
AIG
Differential analogue input
Can be used in pairs with AI 3
18
AI 3
Differential analog input channel 3
Differential analog input pin, forming input with AIG
19
AIG
Differential analogue input
Can be used in pairs with AI 2
20
AI 2
Differential analog input channel 2
Differential analog input pin, forming input with AIG
21
AIG
Differential analogue input
Can be used in pairs with AI 1
22
AI 1
Differential analog input channel 1
Differential analog input pin, forming input with AIG
23
Ethernet
Mesh port
Ethernet Connection Port
24
Reload
Reset button
Long press 5s to work
25
NC 1
Normally closed pin of Relay 1
Cooperate with common end of relay 1
26
COM 1
Relay 1 Common End
Cooperate with the normally open/closed pin of relay 1
27
NO 1
Normally open pin of Relay 1
Cooperate with common end of relay 1
28
NC 2
Normally closed pin of Relay 2
Cooperate with common end of relay 2
29
COM 2
Relay 2 Common End
Cooperate with the normally open/closed pin of relay 2
30
NO 2
Normally open pin of Relay 2
Cooperate with common end of relay 2
31
NC 3
Normally closed pin of Relay 3
Cooperate with common end of relay 3
32
COM 3
Relay 3 Common End
Cooperate with the normally open/closed pin of relay 3
33
NO 3
Normally open pin of Relay 3
Cooperate with common end of relay 3
34
NC 4
Normally closed pin of Relay 4
Cooperate with common end of relay 4
35
COM 4
Relay 4 Common End
Cooperate with the normally open/closed pin of relay 4
36
NO 4
Normally open pin of Relay 4
Cooperate with common end of relay 4
37
Ground screw
Connected to the earth
Connected to the earth
LED light
AI 1
Differential analog input channel 1 indication
Green LED, lights up when input ≥0.5mA
AI 2
Differential analog input channel 2 indication
Green LED, lights up when input ≥0.5mA
AI 3
Differential analog input channel 3 indication
Green LED, lights up when input ≥0.5mA
AI 4
Differential analog input channel 4 indication
Green LED, lights up when input ≥0.5mA
DI 1
Switch Input Channel 1 indication
Green LED,lights up when DI 1、DIG short connect
DI 2
Switch Input Channel 2 indication
Green LED,lights up when DI 2、DIG short connect
DI 3
Switch Input Channel 3 indication
Green LED,lights up when DI 3、DIG short connect
DI 4
Switch Input Channel 4 indication
Green LED,lights up when DI 4、DIG short connect
DO 1
Relay 1 output indication
Green LED,lights up when NO 1, COM 1 closed
DO 2
Relay 2 output indication
Green LED,lights up when NO 2, COM 2 closed
DO 3
Relay 3 output indication
Green LED,lights up when NO 3, COM 3 closed

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DO 4
Relay 4 output indication
Green LED,lights up when NO 4, COM 4 closed
NET
Network indication
Yellow LED, long bright after entering the network
DATA
Serial data indication
Yellow LED, lights up when there’s data transmitted in RS485
interface (expressively flashes)
WORK
Work/reset indication
Yellow LED, flashing regularly / flashing after successful reset
PWR
Power indicator
Red LED, long bright
Note:
Grounding: It is recommended to connect the housing to the ground.
2.3. Reload touch button description
Long press 5S is valid, after the reset is successful, the WORK lamp flashes quickly, and the Modbus device address,
RS485 serial port baud rate and check digit are restored to the factory settings.
3. Modbus
3.1. Modbus address table
Register address table（function code：0x01H、0x05H、0x0FH、0x03H、0x06H、0x10H）
Register address
Register
quantity
Register attribute
Register type
Register value range
Support
function code
00017 (0x0010)
1
DO1 Switch Output
Read / write
0x0000 or 0xFF00
（0x05function code）
0-1
（0x01、
0x0Ffunction
code）
0x01
0x05
0x0F
00018 (0x0011)
1
DO2 Switch Output
Read / write
00019 (0x0012)
1
DO3 Switch Output
Read / write
00020 (0x0013)
1
DO4 Switch Output
Read / write
Reserve
10017 (0x0010)
1
DI1 Switch input
Read only
0-1
0x02
10018 (0x0011)
1
DI2 Switch input
Read only
10019 (0x0012)
1
DI3 Switch input
Read only
10020 (0x0013)
1
DI4 Switch input
Read only
Reserve
30017 (0x0010)
1
AI1 input value，Unit(uA)
Read only
0-20000
0x03
0x04
30018 (0x0011)
1
AI2 input value，Unit(uA)
Read only
30019 (0x0012)
1
AI3 input value，Unit(uA)
Read only
30020 (0x0013)
1
AI4 input value，Unit(uA)
Read only
Reserve
40049 (0x0030)
1
DI1 pulse counting value
Read only
0-65535
0x03
40050 (0x0031)
1
DI2 pulse counting value
Read only
0-65535
40051 (0x0032)
1
DI3 pulse counting value
Read only
0-65535
40052 (0x0033)
1
DI4 pulse counting value
Read only
0-65535
Reserve

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40065 (0x0040)
1
DI1-DI4 Pulse count clear
Write
only
0x00 - 0x0F
0x06
Reserve
40078 (0x004D)
1
Device address
Read/write
1 - 247
0x03
0x06
0x10
40079 (0x004E)
1
Baud rate
Read/write
0 - 7
40080 (0x004F)
1
Parity bit
Read/write
0 - 2
40081(0x0050)
1
Host mode or slave mode
Read/write
0 - 1
40082 (0x0051)
1
Automatic report of switch
qty
Read/write
0 - 2
40083 (0x0052)
1
Switch output time setting
(ms)
Read/write
300-65535
40084(0x0053)
1
Analog range setting
Read/write
0 - 1
40085 (0x0054)
1
Switch restart output status
setting
Read/write
0x00 - 0x10
Reserve
40100 (0x0063)
22
Server IP or domain name
(domain name ASCII)
Read/write
--
0x03
0x06
0x10
40122 (0x0079)
1
Server Port
Read/write
1 - 65535
40123 (0x007A)
1
Protocol type (UDP、TCP)
Read/write
0 - 1
40124(0x007B)
22
Custom registration
package
Read/write
--
40146(0x0091)
1
Registration package
mechanism
Read/write
0 - 4
40147(0x0092)
22
Heartbeat package
Read/write
--
40169（0x00A8)
1
Heartbeat packet time
Read/write
0 - 65535
40170（0x00A9)
1
Heartbeat packet mode
Read/write
0 - 1
40171（0x00AA)
1
Cloud transparent
transmission
Read/write
0 -1
40172（0x00AB）
3
Active connection
Read/write
0，2-7200
40173（0x00AE）
1
Ethernet timeout restart
Read/write
0，60-65535
40174（0x00AF）
1
Clear cache
Read/write
0 - 1
40175（0x00B0）
1
Local port number
Read/write
0-65535
40176（0x00B1）
1
IP acquisition method
Read/write
0 -1
40177（0x00B2）
11
Local IP address
Read/write
--
40188（0x00BD）
11
Subnet mask
Read/write
--
40199（0x00C8）
11
Gateway
Read/write
--
40210（0x00D3）
11
Preferred DNS
Read/write
--
40221(0x00DE)
11
Standby DNS
Read/write
--
40232（0x00E9)
11
MAC value
Read only
--
0x03
40243（0x00F4)
11
SN code value
Read only
--
Reserve
40300(0x012B)
1
version number
Read only
--
0x03
3.2. Modbus Address Table
Modbus address table
1（default）
1

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2
2
3
3
…
…
245
245
246
246
247
247
3.3. RS485 Serial Port Baud Rate Code Table
Baud Rate Code Table
0
1200
1
2400
2
4800
3（default）
9600
4
19200
5
38400
6
57600
7
115200
3.4. RS485 serial port check bit value table
check bit value table
0（default）
No check
1
even parity check
2
Odd parity check
3.5. Host computer configuration parameters
Select the "Parameter Settings" column, you can read parameters, write parameters. For the specific realization of
functions, see the product functions described below.

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4. Product Function
4.1. Working mode
The working mode has host mode and slave mode, which is configured by Modbus register 40081 (0x0050). It will be
Host mode when the register value is 0; slave mode when the register value is 1, default slave mode.
4.1.1.Slave mode
In slave mode (register value 0x01), the data sent to the device by the network or 485 terminal (sender) satisfies the
Modbus RTU, Modbus TCP protocol, and the address in the data is the device address, and the device will reply with the
same protocol. If the data sent by the network or 485 bus to the device does not satisfy the Modbus RTU, Modbus TCP
protocol, or the Modbus RTU or Modbus TCP protocol is met but the data address is not the device address, the data of
the sender will be discarded.
In slave mode, the device can connect to the device in host mode directly through 485 bus, so that the data of slave can
also be accessed by the network terminal when the slave is not connected to the network.

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4.1.2. Host mode
In host mode (register value is 0x00), the data sent by the network or 485 bus (transmitter) to the device satisfies the
Modbus RTU, Modbus TCP protocol, and the address in the data is the device address, and the device responds to the
sender with the same protocol. If the data sent by the network or 485 bus to the device does not satisfy the Modbus RTU,
Modbus TCP protocol, or satisfy the Modbus RTU, Modbus TCP protocol but the data address is not the device address,
the data from the 485 bus will be transmitted to the network, and the data from the network will be transmitted to the 485
bus.
This function of host mode can realize the cascade function of devices and the data transmission between 485 bus and
network.

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4.2. Basic functions of IO
4.2.1. Switch DO Output
4.2.1.1 Read Switch DO Output
Function code: 01, read coil status
Address range: 00017 (0x0010) ~ 00020 (0x0013)
Explanation: When equipment relay passive output and coil is not powered on, relay NC port and COM port are usually
closed, NO port and COM port are often open, with a value of 0; when coil is energized, the phenomenon is opposite,
relay NC port and COM port are disconnected, NO port and COM port are closed, with a value of 1. Query relay status
by instruction.
Example:
Read the 4-way switch output state, assuming a return value of 03, corresponding to the binary bit 0000 0011, the lower
four bits and four bits represent the switch output state, which in turn is DO4, DO3, DO2, DO1.
Modbus RTU protocol reads switching output:
Transmit
01
01
00 10
00 04
3C 0C
Device ModBus address
Function code
Switch start address
Read switch quantity
CRC check code
Receive
01
01
01
03
11 89
Device ModBus address
Function code
Return bytes
Switch output value
CRC check code

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Modbus TCP protocol reads switching output:
Transmit
00 01
00 00
00 06
01
01
00 10
00 04
Transmission
identifier
Protocol
identifier
length
Unit
identification
Function
code
Switch start
address
Read switch
quantity
Receive
00 01
00 00
00 04
01
01
01
03
Transmission
identifier
Protocol
identifier
length
Unit
identification
Function
code
Return bytes
Switch Output
Value
4.2.1.2. Control switch quantity DO output
Function code: 05, write single coil state; 0F, write multiple coil state
Address range: 00017 (0x0010) ~00020 (0x0013)
Description: Equipment relay passive output, coil is not energized, relay NC port and COM port are closed, NO port and
COM port are disconnected; coil is energized, relay NC port and COM port are disconnected, NO port and COM port are
closed. The state of relay is controlled by command.
Example:
Function code 0x05 write DO2 switch output, make NC2, COM2 open, NO2, COM2 close, write value is FF 00; make
NC2, COM2 close, NO2, COM2 open, write value 00 00.
Modbus RTU protocol write switch output:
Transmit
01
05
00 11
FF 00
DC 3F
Device ModBus address
Function code
Switching address
Write value
CRC check code
Receive
01
05
00 11
FF 00
DC 3F
Device ModBus address
Function code
Switching address
Write value
CRC check code
Modbus TCP protocol write switch output:
Transmit
00 01
00 00
00 06
01
05
00 11
FF 00
Transmission
identifier
Protocol
identifier
length
element ID
Function code
Switching address
Write value
Receive
00 01
00 00
00 06
01
05
00 11
FF 00
Transmission
identifier
Protocol
identifier
length
element ID
Function code
Switching address
Write value

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Function code 0x0F writes DO2, DO3 switch output, making NC2, COM2 disconnected, NO2, COM2 closed; NC3,
COM3 disconnected, NO3, COM3 closed. Write value should be 0x03, corresponding to binary bit 0000 0011
Modbus RTU protocol write switch output:
Transmit
01
0F
00 11
00 02
01
03
62 95
Device ModBus
address
Function code
Switching address
Write switch
quantity
Bytes
Write value
CRC check
code
Receive
01
0F
00 11
00 02
84 0F
Device ModBus address
Function code
Switching address
Write value
CRC check code
Modbus TCP Write Switch Output:
Transmit
00 01
00 00
00 08
01
0F
00 11
00 02
01
03
Transmission
identifier
Protocol
identifier
length
element
ID
Function
code
Switching
address
Write Switch
Quantity
Bytes
Write
value
Receive
00 01
00 00
00 06
01
0F
00 11
00 02
Transmission
identifier
Protocol
identifier
length
element ID
Function code
Switching
address
Write Switch Quantity
4.2.2. Read switch DI input
Function Code: 02, Read (Switch) Input Status
Address range: 10017 (0x0010) ~10020 (0x0013)
Description: Default Dry Contact Input for Device, when DI and COM are short connected, the read value should be 1;
when DI and COM are not short connected, the read value should be 0.
Example:
Read 4 way switch input value, In DI input terminal, DI1, COM1 short connection, DI2, COM2 are not short connection,
DI3, COM3 short connection, DI4, COM4 are not short connection. The input digital input value is 0x05, corresponding
to the binary bit 0000 0101, and the four bits of the lower four bits represent the digital input value, which are in turn DI4,
DI3, DI2, DI1.
Modbus RTU protocol reads switching input:
Transmit
01
02
00 10
00 04
78 0C
Device ModBus
address
Function code
Switch start address
Read the quantity of
switches
CRC check code

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Receive
01
02
01
05
61 8B
Device ModBus
address
Function code
Return bytes
Switch Input Value
CRC check code
Modbus TCP protocol reads switch input:
Transmit
00 01
00 00
00 06
01
02
00 10
00 04
Transmission
identifier
Protocol
identifier
length
element ID
Function
code
Switch start address
Read the quantity
of switches
Receive
00 01
00 00
00 04
01
02
01
05
Transmission
identifier
Protocol
identifier
length
element ID
Function
code
Return bytes
Switch Input Value
4.2.3. Read analog AI input
Function code: 03, read holding register; 04, read input register
Address range: 30017 (0x0010) ~30020 (0x0013)
Note: The input unit of differential analogue is uA.
Example:
Function code 0x03, read AI1 input, assuming AI1 input is 9946uA, the corresponding value should be 0x0x26DA
The Modbus RTU protocol reads the differential analog input:
Transmit
01
03
00 10
00 01
85 CF
Device ModBus
address
Function code
Analog start address
Read quantity
CRC check code
Receive
01
03
02
26 DA
23 BF
Device ModBus
address
Function code
Return bytes
Input value of
differential analogue
CRC check code