SST Automation GT100-MQ-IE User manual

Modbus / Modbus TCP / MQTT Gateway
GT100-MQ-IE
User Manual
V 3.0
REV A
SST Automation
Email: [e-mail]
[e-mail]
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Important Information
Warning
The data and examples in this manual cannot be copied without authorization. SST Automation reserves the right
to upgrade the product without notifying users.
The product has many applications. The users must make sure that all operations and results are in accordance
with the safety of relevant fields, and the safety includes laws, rules, codes and standards.
Copyright
Copyright © 2022 by SST Automation. All rights reserved.
Trademark
is the registered trade mark of SST Automation.
Technical Support Contact Information
www.sstautomation.com
E-mail: [e-mail]

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Catalog
1 Product Overview ......................................................................................................................................................1
1.1 Product Function ............................................................................................................................................ 1
1.2 Product Feature ...............................................................................................................................................2
1.3 Technical Specifications .................................................................................................................................3
1.4 Related Products .............................................................................................................................................5
1.5 Revision History .............................................................................................................................................5
2 Hardware Descriptions .............................................................................................................................................. 6
2.1 Product Appearance ........................................................................................................................................6
2.2 LED Indicators ............................................................................................................................................... 7
2.3 Configuration Button ......................................................................................................................................7
2.4 Interface .......................................................................................................................................................... 8
2.4.1 Power Interface ................................................................................................................................... 8
2.4.2 RS485 Serial Interface ........................................................................................................................ 8
2.4.3 Ethernet Interface ................................................................................................................................ 9
2.4.4 Nano SIM Card Slot ............................................................................................................................9
3 Hardware Installation .............................................................................................................................................. 10
3.1 Machine Dimension ..................................................................................................................................... 10
3.2 Installation Method ...................................................................................................................................... 10
4 Quick Start Guide .................................................................................................................................................... 11
4.1 Connection ....................................................................................................................................................11
4.2 Configuration ................................................................................................................................................12
5 Software Instructions ...............................................................................................................................................16
5.1 Software Interface Description .................................................................................................................... 16
5.2 Wireless Internet .......................................................................................................................................... 18
5.2.1 NB-IoT/eMTC ...................................................................................................................................18
5.2.2 Advanced Config ...............................................................................................................................20
5.2.3 MQTT Topic ......................................................................................................................................22
5.3 Modbus TCP Client / Server Configuration .................................................................................................23
5.3.1 Modbus TCP Client Configuration ................................................................................................... 23
5.3.2 Modbus TCP Server Configuration .................................................................................................. 26
5.4 Subnet Configuration ................................................................................................................................... 27
5.4.1 Modbus Master Interface configuration ............................................................................................29
5.4.2 Modbus Slave Interface Configuration .............................................................................................32
5.5 GPS ...............................................................................................................................................................33
5.6 Tool ............................................................................................................................................................... 33
5.6.1 Upload Config and Download Config .............................................................................................. 34
5.6.2 AutoMap ............................................................................................................................................36
5.6.3 Confilict Detection ............................................................................................................................ 36
5.6.4 Export Excel ......................................................................................................................................37
5.6.5 Traffic Forecast ................................................................................................................................. 37

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5.6.6 Remote Update Server File ............................................................................................................... 38
5.7 Property Operations ......................................................................................................................................39
5.7.1 Property Configuration ......................................................................................................................39
5.7.2 Name Properties in Order ................................................................................................................. 40
5.7.3 Properties Name Conflict Detection ................................................................................................. 40
6 Working Principle ....................................................................................................................................................41
6.1 Connection Process ...................................................................................................................................... 41
6.2 Data Exchange ..............................................................................................................................................42
Appendix A: MQTT Message Format ....................................................................................................................... 43
A.1 Default Format .............................................................................................................................................43
A.2 Custom Message Format .............................................................................................................................48
Appendix B: Change Product Firmware Mode ..........................................................................................................50

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1 Product Overview
1.1 Product Function
The GT100-MQ-IE is a RS485 and 10/100M-RJ45 based wireless gateway with GPS function. The gateway can
connect Modbus RTU/ASCII and Modbus TCP devices to the IoT Cloud by MQTT. Wireless networks support
eMTC and NB-IoT,It supports the MQTT connection to various IoT cloud platforms, such as Amazon AWS IoT,
Microsoft Azure IoT and generic MQTT servers.
Note:The authentication method to connect to AWS or Azure, you need to use a security certificate.
GT100-MQ-IE integrates two firmware modes, which can be switched by downloading the BIN file of the
corresponding mode. For details, please refer to Appendix B.
The following table shows the specific functions corresponding to the two modes:
Firmware Mode
Description
A: Modbus TCP Client / Modbus Master
Modbus TCP Client, Modbus RTU/ASCII Master
B: Modbus TCP Server/ Modbus Master-Slave
Modbus TCP Server, Modbus RTU/ASCII Master/Slave
The GT100-MQ-IE is wildly used in unmanned industrial spots such as water quality monitor stations,
environmental monitor stations, intelligent building systems, intelligent agriculture systems, and energy and
electricity systems that require remote monitoring.

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Modbus RTU/ASCII and Modbus TCP devices to the IoT Cloud by MQTT
1.2 Product Feature
One RS485 Interface - Modbus Master/Slave
As Modbus Master: Connects field devices to the IoT Cloud Platform, implementing data acquisition
and device control via eMTC / NB-IoT network.
As Modbus Slave: Integrates PLC, DCS and other Modbus master station with the IoT Cloud Platform
via eMTC / NB-IoT network.
One Ethernet Interface - Modbus TCP Client/Server

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As Modbus TCP Client: Connects Modbus TCP Server devices, such as intelligent instruments.
As Modbus TCP Server: Connects Modbus TCP Client devices, such as SCADA systems.
Supports GPS.
eMTC / NB-IoT network is always online. Supports connection detect and auto reconnect functions.
Supports MQTT broker URL connection.
TLS V1.2 and DTLS 1.0/1.2. Supports custom Client ID.
Supports MQTT version 3.1.1. Uses JSON format to upload data to the cloud platform, users can customize
the JSON content format.
QoS 0 and 1 supported.
Supports two publish mode:
1Publish when data changes.
2Publish periodically at custom cycle time, which can reduce the data traffic.
Supports two Message Types: Register message or Property message.
Real-time device status monitoring on the IoT Cloud Platform.
eMTC / NB-IoT network quality detection and display.
Applies to industrial field with high reliability. Supports real-time monitoring and automatic reset.
1.3 Technical Specifications
[1] eMTC / NB-IoT network
Supported standard:
● CAT-M(eMTC): B1/B2/B3/B4/B5/B8/B12/B13/B14/B18/B19/B20/B25/B26/B27/B28/B66/B85
● CAT-NB(NB-IoT): B1/B2/B3/B4/B5/B8/B12/B13/B18/B19/B20/B25/B26/B28/B66/B71/B85
Note: APN (Access point name) identifies the mobile network type. The APN is automatically obtained
by default. Users can configure the APN if they have special requirements.
Transmission speed:
● CAT-M: Uplink: 1119Kbps; Downlink:589Kbps
● CAT-NB: Uplink: 150Kdps; Downlink:136Kdps

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[2] One serial interface
Physical standard: RS485.
Parity: Odd, Even, None, Mark, Space.
Stop bits: 1 or 2.
Baud rate: 600~115200 bps.
Protocol: Modbus RTU/ASCII Master/Slave.
Modbus Function codes: 01, 02, 03, 04, 05, 06, 15, 16.
Interface type: 3.81 mm 3-pin port.
Galvanic isolation: 1kV photoelectric isolation.
[3] One Ethernet interface
Physical standard: RJ45, full-duplex / half-duplex.
Speed: 10/100 Mbps, auto-detected.
Protocol: Modbus TCP Client/Server (supports Function codes: 01, 02, 03, 04, 05, 06, 15, 16).
Supports DHCP and Manual Assign.
[4] Maximum data and connections:
Modbus RTU/ASCII:
Input bytes ≤ 512 bytes
Output bytes ≤ 512 bytes
Maximum connections: 31 serial devices
Maximum commands: 100 commands (as Modbus master)
Modbus TCP:
Input bytes ≤ 512 bytes
Output bytes ≤ 512 bytes
Maximum connections: 4 Clients or 4 Servers
Maximum commands: 100 commands (as Modbus TCP Client)
Maximum properties:
The maximum total number of all the properties that can be configured on the configuration software:
1000 properties.

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[5] Power: 24 VDC (11~30 VDC)
[6] Operating temperature: -4°F~140°F (-20°C~60°C). Humidity: 5%~95% (non-condensing).
[7] Dimensions: 1.0 in * 4.0 in * 3.6 in (25 mm * 100 mm * 90 mm).
[8] Installation: 1.4 in (35 mm) DIN RAIL.
[9] Protection level: IP20.
1.4 Related Products
The related products include: GT200-MQ-IE etc.
To get more information about related products, please visit SSTCOMM website: www.sstautomation.com.
1.5 Revision History
Revision
Date
Chapter
Description
V3.0, REV A
12/24/2021
ALL
New release

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2 Hardware Descriptions
2.1 Product Appearance
Note: This picture is for reference only. The product appearance is subject to the actual product.
LED Indicators
GPS Antenna
Ethernet Interface
Power Interface
NB-IoT/eMTC
Antenna
RS485 Interface
Button
Nano SIM Card Slot

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2.2 LED Indicators
Indicator
State
State description
STA
OFF
The wireless module is not started.
Green, slow blinking
(200 ms ON / 1800 ms OFF)
The gateway is searching available network.
Green, slow blinking
(1800 ms ON / 200 ms OFF)
The wireless module is in standby.
Green, quick blinking
(125 ms ON /125 ms OFF)
Data transmission via wireless module.
SG
Green,OFF
The SIM card is invalid.
Green, ON
The connection is being established or could not be
established.
Green, slow blinking
(1000 ms ON / 1000 ms OFF)
Poor signal
Green, blinking
(500 ms ON / 500 ms OFF)
Weak signal
Green, quick blinking
(200 ms ON / 200 ms OFF)
Strong signal
TX/RX
Green, blinking / OFF
The RS485 interface receives/receives no data.
Red,blinking / OFF
The RS485 interface Sends / Sends no data.
ENS
Green, slow blinking
No Modbus TCP connection.
Green, quick blinking
Fixed IP Address: 192.168.0.10
Red, blinking
Locating the gateway / Disconnect after successful TCP
connection.
Green,ON
Modbus TCP connections.
2.3 Configuration Button
The function and operation instructions of the buttons are as follows:

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Button action
Function Description
Long press for 3 seconds
The IP address is set to 192.168.0.10 and the ENS is blinking green quickly. Press
the button again to set back to normal status.
(This function can be used if you do not know the IP address of the gateway or
cannot search the gateway using the configuration software.)
Double press
Uploading/downloading configuration is disabled. The GT100-MQ-IE can be
searched but can’t be configured. Press the button again to set back to normal
status.
(This function can be used to prevent this gateway from being modified by others.
For example, when there are multiple GT100-MQ-IEs in the LAN, misoperation is
likely to occur.)
Press and then power on
This function is used to modify the mode of the gateway to adapt to support
different Modbus protocol content.
Please refer to Appendix B for specific operation steps.
2.4 Interface
2.4.1 Power Interface
GND
NC
24V+
1
2
3
2.4.2 RS485 Serial Interface
The GT100-MQ-IE has a RS485 serial interface. The interface is a 3-pin port and the wiring is as follows:
Pin
Function
1
Power ground
2
Not connected
3
24V+, DC
Pin
Function
1
GND
2
D-
3
D+

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RS485 Specification:
1. Network topology: Linear bus with active terminal resistors at both sides. If the communication quality is
unstable, it can be considered to add terminal resistor (120Ω, 1/2W) at both ends.
2. Physical Media: Shielded twisted-pair cable that also can cancel the shielding, depending on environmental
conditions (EMC).
3. Station number: 31 stations per section (without repeater), and up to 127 stations in total (with repeaters).
2.4.3 Ethernet Interface
The Ethernet interface is a RJ45 socket.
2.4.4 Nano SIM Card Slot
Please use NB card (for CAT-NB network) or eMTC card (for CAT-M network).
Format: Nano-SIM (4FF)
Length * Width: 12.3mm * 8.8 mm (0.48 in * 0.35 in)
Thickness: 0.67 mm (0.026 in)
Pin
Signal description
S1
TXD+
S2
TXD-
S3
RXD+
S4
-
S5
-
S6
RXD-
S7
-
S8
-

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3 Hardware Installation
3.1 Machine Dimension
Size (width * height * depth):
1.0 in * 4.0 in * 3.6 in (25 mm * 100 mm * 90 mm)
3.2 Installation Method
Using 1.4 in (35mm) DIN RAIL.

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4 Quick Start Guide
4.1 Connection
1. Insert the Nano SIM card into the slot behind the GT100-MQ-IE correctly.
2. Connect NB-IoT /eMTC network antenna (long straight antenna) and GPS antenna (square head antenna).
3. Connect the power supply as follows.
Note: Please do not power on the devices before finishing all the connections.
24V+
24V DC Power
GND
NC
24V+
GT100-MQ-IE Power
GND
4. Connect the serial devices.
Note: The GT100-MQ-IE doesn’t have the terminal resistor in the RS485 serial interface. When connecting
multiple RS485 serial devices, it’s recommended to connect a terminal resistor (120Ω, 1/2W) in parallel at
both ends of the communication lines to ensure stable communication.

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5. Connect the Modbus TCP clients/servers via Ethernet cable.
6. Connect the GT100-MQ-IE with the PC via Ethernet cable.(Use when configuring)
7. Power on the GT100-MQ-IE.
4.2 Configuration
1. Download the configuration software SST-MQT-CFG from https://www.sstautomation.com/Download1/ and
install it. Open the software and select the GT100-MQ-IE, then confirm the gateway mode.
2. Configure the Wireless Internet (MQTT Server configuration).

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3. Add or edit MQTT Topic.
4. Configure the Modbus TCP and Subnet Interface parameters.

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5. Configure the properties.
6. Check the mapping buffer and the property names. Use the “Auto Mapping” and “Name Properties in Order”
functions.
7. Save the configuration and download to GT100-MQ-IE through network cable configuration.

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Notes：
1Make sure that the GT100-MQ-IE and your computer are in the same network segment.
2If you can’t discover any gateways, please test the network connection first. Please refer to the note
“How to Use the Ping Command” located on our Support page on the sstautomation.com website.
3If the Assign IP mode is DHCP, and there is no DHCP Server or you can’t search the GT100-MQ-IE.
Please power on, then press and hold the button for 3 seconds. At this time, the IP address is restored to
192.168.0.10, and the device can be searched under the same network segment as the gateway and computer, and
the configuration can be uploaded and downloaded.

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5 Software Instructions
SST-MQT-CFG is the configuration software which can be used to configure GT100-MQ-IE.
It can be downloaded from the product page or Download page( www.sstautomation.com/Download1/) of
website.
The software is based on Windows OS.
Operating System: Win7, Win10.
5.1 Software Interface Description
Double click on the SST-MQT-CFG icon to enter Device Select interface.
Select “GT100-MQ-IE” and click OK, then select the mode:
Note: Please select Mode according to the actual Firmware type in GT100-MQ-IE. The default factory firmware
mode is “A: Modbus TCP Client / Modbus Master”. If you want to change the firmware model of the gateway,
please refer to Appendix B.