Ebyte E851-RTU User manual

Chengdu Ebyte Electronic Technology Co., Ltd.
E851-RTU(4440-ETH) User Manual
Copyright © 2012–2019, Chengdu Ebyte Electronic Technology Co., Ltd.

Chengdu Ebyte Electronic Technology Co., Ltd. E851-RTU(4440-ETH) User Manual
Copyright © 2012, Chengdu Ebyte Electronic Technology Co., Ltd.
2
Contents
Features ................................................................................................................................................................................. 3
1 Quick Start .........................................................................................................................................................................4
1.1 port connection........................................................................................................................................................ 4
1.1.1 RS485 connection.................................................................................................................................................4
1.2 Quck Use ..................................................................................................................................................................5
1.2.1 RS485 bus control.................................................................................................................................................6
2 Product Introduction ........................................................................................................................................................ 9
2.1 Basic parameters......................................................................................................................................................9
2.2 Dimensions, interface description..........................................................................................................................10
2.3 Description of Reload touch button .......................................................................................................................13
3 Modbus .............................................................................................................................................................................14
3.1 Modbus address table.............................................................................................................................................14
3.2 Modbus address table.............................................................................................................................................15
3.3 RS485 serial port baud rate code value table.........................................................................................................15
3.4 RS485 serial port parity code value table.............................................................................................................. 16
3.5 Configure parameters through the host computer..................................................................................................16
4 Product Functions ........................................................................................................................................................... 17
4.1 Working mode .............................................................................................................................................................. 17
4.2 IO basic functions .........................................................................................................................................................18
4.3 IO Features.............................................................................................................................................................22
4.4 Network related functions......................................................................................................................................24
Revision history .................................................................................................................................................................. 32
Contact us ........................................................................................................................................................................... 32

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E851-RTU(4440-ETH ) Features
Support 4 differential analog inputs, default current detection;
Support 4 digital inputs, default dry contact;
Support 4 relay outputs;
Support socket connection to remote server, support TCP Client;
Using Modbus TCP/RTU protocol data processing;
Support connection to Ebyte cloud, command control;
Support 2 working modes, host mode and slave mode, the slave can cascade multiple devices through RS485;
Support Reload touch button, long press for 5s, Modbus device address, RS485 serial port baud rate and parity digit restore
factory settings;
Hardware watchdog with high reliability;
Multiple indicator lights show working status;
The power supply has good over-current, over-voltage, anti-reverse and other functions.
Note: Customers can customize functions, such as conditional control (determine how to output according to the input state)

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1 Quick Start
This chapter is a quick introduction to the E851-RTU (4440-ETH) series products. It is recommended that users systematically
read this chapter and follow the instructions to have a systematic understanding of the module products. Users can also choose what
you are interested in according to their needs. chapters to read. For specific details and instructions, refer to subsequent 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, and the
signal will form a reflected wave at the end of the transmission line, which will interfere with the original signal. Therefore, it is
necessary to add a terminal resistor at the end of the transmission line so that the signal does not reflect after reaching the end of the
transmission line. The terminal resistance should be the same as the impedance of the communication cable, the typical value is 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 Digital input connection
1.1.3 Relay output connection
1.1.4 Differential Analog Input Connections
1.2 Quck Use
Wiring: Computer connects to E851-RTU (4440-ETH) via USB to RS485
Networking: the network cable is inserted into the RJ45 port
Power supply: E851-RTU (4440-ETH) working voltage is DC 8~28V

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1.2.1 RS485 bus control
Select the corresponding port and click Search to search for devices.
After the device is found, click Stop .
At this time, you can see the device address of the current device, and for the "automatic refresh" √ process, you can perform
switch output control, switch input reading, and differential analog input reading .

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1.2.2 Network acquisition control (static IP connection directly controls the product)
Step preview: network control hardware connection - PC computer settings - product connection parameter setting - use network
debugging tools to connect products - send control/acquisition instructions
(1) Network acquisition control hardware connection: use a network cable to directly connect the computer network port to this
product, and use a USB to RS485 tool to connect the computer USB to the product RS485.

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(2) PC-side computer settings: set the computer to a static IP, the steps are as shown in the figure below.
（3）Product connection parameter setting: as shown in the figure below (default factory setting).

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（4）Connect to the product with a network debugging tool: here we take the sscom .exe debugging tool as an example.
1 Open a TCPServer service——2 Output the server IP connected to the product: 192.168.4.101 and service port
8886——3 Click Listen (that is, connect to the product, if the word "Listen" cannot be grayed out, please check the above
Parameter setting and hardware connection) - 4 Set data sending rules - 5 Edit product instructions (the picture shows reading the
AI1 channel acquisition value, see " Chapter 4 Product Functions " for more instructions) - 6 Click "Send" ——7 Return
message received——successful.
（5）See " 4.1 Working Mode " for more connection methods.
2 Product Introduction
E851-RTU (4440-ETH) is a network IO product that supports 4 digital inputs (default dry contact), 4 differential analog inputs,
and 4 relay outputs. Support Modbus TCP/RTU protocol. The product is highly usable, and users can easily and quickly integrate it
into their own systems to realize Ethernet-based remote control.
2.1 Basic parameters
project
index
hardware parameters
Product size (H*W*D)
172*107*29mm
product weight
457.5± 5g
Operating temperature
-20℃~+70℃
storage temperature
-40℃~+85℃
Working humidity
5%~95%
storage humidity
1%~95%
Operating Voltage
8V~28V

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Current acquisition range
0mA~20mA
precision
0.2%
Data interface
RS485: 1200~115200bps
software parameters
Network Type
ethernet
configuration command
Modbus TCP/RTU
Network protocol
Modbus TCP/RTU
Operating mode
Master mode, slave mode
data transfer method
TCP Client
2.2 Dimensions, interface description

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serial number
Port and other
definitions
Features
illustrate
1
DC-IN seat
DC socket 5.5*2.1mm
Power input terminal, DC 8V~28V, 12V/24V is
recommended, and it cannot be powered at the same
time as the crimping terminal
2
DC-IN+
Pressure wire type power
input positive pole
Power input, DC 8V~28V, it is recommended that
12V/24V cannot be powered simultaneously with the
DC socket
3
DC-IN -
Negative pole of crimping
power input
power reference ground
4
RS485B
RS485 interface B
RS485 interface B is connected to device B interface
5
RS485A
RS485 interface A
RS485 port A is connected to device A port
6
RS485G
signal reference ground
Signal reference ground, may not be connected
7
DIG
switch input ground
Can be paired with DI 4
8
DI 4
Digital input channel 4
Form dry contact with DIG
9
DIG
switch input ground
Pair with DI 3
10
DI 3
Digital input channel 3
Form dry contact with DIG
11
DIG
switch input ground
Can be paired with DI 2
12
DI 2
Digital input channel 2
Form dry contact with DIG
13
DIG
switch input ground
Can be used as a pair with DI 1
14
DI 1
Digital input channel 1
Form dry contact with DIG
15
AIG
Differential analog input
ground
Can be paired with AI 4
16
AI 4
Differential analog input
channel 4
Differential analog input pin, forms input with AIG
17
AIG
Differential analog input
Can be paired with AI 3

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ground
18
AI 3
Differential analog input
channel 3
Differential analog input pin, forms input with AIG
19
AIG
Differential analog input
ground
Can be paired with AI 2
20
AI 2
Differential analog input
channel 2
Differential analog input pin, forms input with AIG
twenty one
AIG
Differential analog input
ground
Can be paired with AI 1
twenty two
AI 1
Differential analog input
channel 1
Differential analog input pin, forms input with AIG
twenty three
Ethernet
Network port
Ethernet port
twenty four
Reload
reset button
Long press 5s to work
25
NC 1
Relay 1 normally closed
pin
Used in conjunction with relay 1 common
26
COM 1
Relay 1 common terminal
Works with Relay 1 normally open pin/normally
closed pin
27
NO 1
Relay 1 normally open pin
Used in conjunction with relay 1 common
28
NC 2
Relay 2 normally closed
pin
Use with Relay 2 Common
29
COM 2
Relay 2 common terminal
Works with Relay 2 normally open pin/normally
closed pin
30
NO 2
Relay 2 normally open pin
Use with Relay 2 Common
31
NC 3
Relay 3 normally closed
pin
Used in conjunction with relay 3 common
32
COM 3
Relay 3 common terminal
Works with Relay 3 normally open pin/normally
closed pin
33
no 3
Relay 3 normally open pin
Used in conjunction with relay 3 common
34
NC 4
Relay 4 normally closed
pin
Use with relay 4 common
35
COM 4
Relay 4 common terminal
Works with Relay 4 normally open pin/normally
closed pin
36
no 4
Relay 4 normally open pin
Use with relay 4 common
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 for sufficiently large input (≥0.5mA)
AI 2
Differential analog input
channel 2 indication
Green LED, lights up for sufficiently large input (≥0.5mA)
AI 3
Differential analog input
channel 3 indication
Green LED, lights up for sufficiently large input (≥0.5mA)
AI 4
Differential analog input
channel 4 indication
Green LED, lights up for sufficiently large input (≥0.5mA)

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DI 1
Digital input channel 1
indication
Green LED, DI 1, DIG short circuit lights up
DI 2
Digital input channel 2
indication
Green LED, DI 2, DIG short circuit lights up
DI 3
Digital input channel 3
indication
Green LED, DI 3, DIG short circuit lights up
DI 4
Digital input channel 4
indication
Green LED, DI 4, DIG shorted on
DO 1
Relay 1 output indication
Green LED, NO 1, COM 1 closed light up
DO 2
Relay 2 output indication
Green LED, NO 2, COM 2 closed light up
DO 3
Relay 3 output indication
Green LED, NO 3, COM 3 closed light up
DO 4
Relay 4 output indication
Green LED, NO 4, COM 4 closed light up
NET
network instructions
Yellow LED, always on after connecting to the network
DATA
Serial port data indication
Yellow LED, lights up when the RS485 interface has data transmission
(expressed as flashing)
WORK
Work/reset indication
Yellow LED, flashes regularly/flashes quickly after successful reset
PWR
Power indicator
Red LED, always on
Notice:
Grounding: It is recommended to connect the shell to the earth
2.3 Description of Reload touch button
Long press for 5 seconds is effective. After the reset is successful, the WORK light flashes quickly, and the Modbus device
address, RS485 serial port baud rate and check digit are restored to factory settings.

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3 Modbus
3.1 Modbus address table
Register address table (function code: 0x01H, 0x05H, 0x0FH, 0x03H, 0x06H, 0x10H)
register address
number
of
registers
Register properties
register
type
Register value
range
Support
function
code
00017 (0x0010)
1
DO1 switch output
read/write
0x0000 or
0xFF00 (0x05
function code)
0-1 (0x01, 0x0F
function 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 count value
read only
0-65535
0x03
40050 (0x0031)
1
DI2 pulse count value
read only
0-65535
40051 (0x0032)
1
DI3 pulse count value
read only
0-65535
40052 (0x0033)
1
DI4 pulse count value
read only
0-65535
reserve
40065 (0x0040)
1
DI1-DI4 pulse count reset
just
write
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
Check Digit
read/write
0 - 2
40081(0x0050)
1
Master mode or slave mode
read/write
0 - 1
40082 (0x0051)
1
Switching value automatic
reporting
read/write
0 - 2
40083 (0x0052)
1
Switching output time setting
(milliseconds)
read/write
300-65535
40084(0x0053)
1
Analog range setting
read/write
0 - 1
40085 (0x0054)
1
Switch value restart output state
setting
read/write
0x00 - 0x10
reserve
40100 (0x0063)
twenty
two
Server IP or domain name
(domain name in 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

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40124(0x007B)
twenty
two
custom registration package
read/write
--
40146(0x0091)
1
Registry Package Mechanism
read/write
0 - 4
40147(0x0092)
twenty
two
heartbeat packet
read/write
--
40169 (0x00A8)
1
Heartbeat packet time
read/write
0 - 65535
40170 (0x00A9)
1
Heartbeat mode
read/write
0 - 1
40171 (0x00AA)
1
cloud transmission
read/write
0-1
40172 (0x00AB)
3
keep alive 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
Alternate 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
2
2
3
3
…
…
245
245
246
246
247
247
3.3 RS485 serial port baud rate code value table
Baud rate code value table
0
1200
1
2400
2
4800
3 (default)
9600
4
19200
5
38400
6
57600
7
115200

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3.4 RS485 serial port parity code value table
check digit code value
table
0 (default)
no parity
1
even parity
2
Odd parity
3.5 Configure parameters through the host computer
Select the "Parameter Setting" column to read and write parameters. For specific functions, see the product function introduction
below.

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4 Product Functions
4.1 Working mode
The working mode is divided into master mode and slave mode, configured through Modbus register 40081 (0x0050). When the
register value is 0, it is the master mode; when the register value is 1, it is the slave mode, and the default slave mode.
4.1.1 Slave mode
In the slave mode (register value is 0x01), the data sent by the network end or the 485 bus end (transmitter) to the device meets
the Modbus RTU and Modbus TCP protocols, and the address in the data is the device address, and the device will respond with the
same protocol to send If the data sent by the network end or 485 bus end to the device does not meet the Modbus RTU, Modbus TCP
protocol, or meets the Modbus RTU, Modbus TCP protocol but the data address is not the device address, the data at the sending end
will be discarded.
In the slave mode, the device can directly connect to the device in the master mode through the 485 bus, so that when the slave is
not connected to the Internet, the network can also access the data of the slave through the master.
4.1.2 Host Mode
In the host mode (the register value is 0x00), the data sent by the network terminal or the 485 bus terminal (transmitter) to the
device meets the Modbus RTU and Modbus TCP protocols, and the address in the data is the device address, and the device will
respond to the sender with the same protocol ; If the data sent by the network end or the 485 bus end to the device does not meet the
Modbus RTU, Modbus TCP protocol, or meets the Modbus RTU, Modbus TCP protocol but the data address is not the device address,

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the data from the 485 bus will be transmitted to the network The data from the network will be transmitted to the 485 bus.
This function of the host mode can realize the device cascading function and the data transmission between the 485 bus and the
network.
4.2 IO basic functions
4.2.1 Digital DO output
4.2.1.1 Read switch DO output
Function code: 01, read coil status
Address range: 00017(0x0010)~00020(0x0013)
Explanation: When the device relay is passive output, when the coil is not powered, the NC port and COM port of the relay are
normally closed, and the NO port and COM port are normally open, and the value is 0; when the coil is powered on, the phenomenon
is opposite, and the relay NC port and COM port are disconnected. Open, the NO port and the COM port are closed, and the value is 1.
Query the status of the relay through the command.
example:
Read the 4-way switching output status, assuming the return value is 03, corresponding to the binary digits 0000 0011, the lower
four bits represent the switching output status, which are DO4, DO3, DO2, DO1 in sequence.
Modbus RTU protocol to read switch output:
send
01
01
00 10
00 04
3C 0C
Device ModBus address
function
code
switch start address
Read switch quantity
CRC check code

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take over
01
01
01
03
11 89
Device ModBus address
function
code
returns the number of
bytes
Switch output value
CRC check code
Modbus TCP protocol to read switch output:
send
00 01
00 00
00 06
01
01
00 10
00 04
Transmissi
on ID
Protocol
ID
length
Unit ID
function
code
switch start address
Read switch
quantity
take over
00 01
00 00
00 04
01
01
01
03
Transmissi
on ID
Protocol
ID
length
Unit ID
function
code
returns the number of
bytes
Switch output value
4.2.1.2 Control switch DO output
Function code: 05, write single coil status; 0F, write multiple coil status
Address range: 00017(0x0010)~00020(0x0013)
Explanation: The device relay is passively output, the coil is not powered, the NC port of the relay is closed to the COM port, and
the NO port is disconnected from the COM port; the coil is powered on, the NC port of the relay is disconnected from the COM port,
and the NO port is closed to the COM port. The state of the relay is controlled by commands.
example:
Function code 0x05 writes DO2 switching output, disconnects NC2 and COM2, closes NO2 and COM2, and writes a value of FF
00; closes NC2 and COM2, disconnects NO2 and COM2, and writes a value of 00 00.
Modbus RTU protocol write switch output:
send
01
05
00 11
FF 00
DC 3F
Device ModBus
address
function code
switch address
write value
CRC check code
take over
01
05
00 11
FF 00
DC 3F
Device ModBus
address
function code
switch address
write value
CRC check code
Modbus TCP protocol write switch output:
send
00 01
00 00
00 06
01
05
00 11
FF 00
Transmissi
on ID
Protocol
ID
length
Unit ID
function
code
switch address
write value
take over
00 01
00 00
00 06
01
05
00 11
FF 00
Transmissi
on ID
Protocol
ID
length
Unit ID
function
code
switch address
write value
Function code 0x0F write DO2, DO3 switch output, make NC2, COM2 open, NO2, COM2 close; make NC3, COM3 open, NO3,
COM3 close. The written value should be 0x03, corresponding to the binary bit 0000 0011
Modbus RTU protocol write switch output:

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send
01
0F
00 11
00 02
01
03
62 95
Device ModBus
address
function code
switch address
Write switch
quantity
Bytes
write
value
CRC check
code
take over
01
0F
00 11
00 02
84 0F
Device ModBus
address
function code
switch address
write value
CRC check code
Modbus TCP protocol write switch output:
send
00 01
00 00
00 08
01
0F
00 11
00 02
01
03
Transmissi
on ID
Protocol
ID
length
Unit ID
function
code
switch
address
Write switch
quantity
Bytes
write
value
take
over
00 01
00 00
00 06
01
0F
00 11
00 02
Transmiss
ion ID
Protocol
ID
length
Unit ID
function
code
switch address
Write switch quantity
4.2.2 Read digital DI input
Function code: 02, read (switch value) input state
Address range: 10017(0x0010)~10020(0x0013)
Note: The device defaults to dry contact input. When DI and COM are short-circuited, the read value should be 1; when DI and
COM are not short-circuited, the read value should be 0.
example:
To read the 4-way switch input value, the DI input terminals DI1 and COM1 are short-circuited, DI2 and COM2 are not
short-circuited, DI3 and COM3 are short-circuited, and DI4 and COM4 are not short-circuited. The read digital input value is 0x05,
corresponding to the binary bit 0000 0101, and the lower four bits represent the digital input value, which are DI4, DI3, DI2, and DI1
in turn.
Modbus RTU protocol to read digital input:
send
01
02
00 10
00 04
78 0C
Device ModBus
address
function code
switch start address
Read switch quantity
CRC check code
take over
01
02
01
05
61 8B
Device ModBus
address
function code
returns the number of
bytes
Switch value input value
CRC check code
Modbus TCP protocol to read digital input:
send
00 01
00 00
00 06
01
02
00 10
00 04
Transmissi
on ID
Protocol
ID
length
Unit ID
function
code
switch start address
Read switch
quantity