Queclink GL521MG User manual

GL521MG User Manual
EGPRS/LTE Cat-M1/LTE Cat-NB2/GNSS Tracker
QSZTRACGL521MGUM0100
Version: 1.00

GL521MG User Manual
QSZTRACGL521MGUM0100
Document Title
GL521MG User Manual
Version
1.00
Date
2021-11-28
Status
Released
Document Control ID
QSZTRACGL521MGUM0100
General Notes
Queclink offers this information as a service to its customers, to support application and
engineering efforts that use the products designed by Queclink. The information provided is
based upon requirements specifically provided to Queclink by the customers. Queclink has not
undertaken any independent search for additional relevant information, including any
information that may be in the customer’s possession. Furthermore, system validation of this
product designed by Queclink within a larger electronic system remains the responsibility of the
customer or the customer’s system integrator. All specifications supplied herein are subject to
change.
Copyright
This document contains proprietary technical information which is the property of Queclink.
Copying of this document, distribution to others or using or communication of the contents
thereof is forbidden without express authority. Offenders are liable to the payment of damages.
All rights are reserved in the event of a patent grant or the registration of a utility model or
design. All specifications supplied herein are subject to change without notice at any time.
Copyright © Queclink Wireless Solutions Co., Ltd. 2021

GL521MG User Manual
QSZTRACGL521MGUM0100
Contents
0. Revision History............................................................................................................................... 1
1. Introduction..................................................................................................................................... 2
1.1. GL521MG Product................................................................................................................ 2
1.2. Reference..............................................................................................................................2
1.3. Terms and Abbreviations......................................................................................................2
2. Product Overview............................................................................................................................ 3
2.1. Product Appearance.............................................................................................................3
2.2. Key Description.....................................................................................................................3
2.3. LED Description.................................................................................................................... 4
2.4. Parts List............................................................................................................................... 5
3. Interface Definition..........................................................................................................................6
4. Getting Started................................................................................................................................ 7
4.1. Opening and Closing the Case..............................................................................................7
4.2. Turning on/off the Device.................................................................................................... 7
4.3. Installing a SIM Card............................................................................................................. 8
5. Installation Precautions................................................................................................................... 9
6. Troubleshooting and Safety Info................................................................................................... 10
6.1. Troubleshooting..................................................................................................................10
6.2. Safety Info...........................................................................................................................10
7. Appendix: Supported Accessories.................................................................................................11

GL521MG User Manual
QSZTRACGL521MGUM0100 1
0. Revision History
Revision
Date
Author
Description of Change
1.00
2021-11-28
Heymi Lin
Initial

GL521MG User Manual
QSZTRACGL521MGUM0100 2
1. Introduction
GL521MG is an IP67 waterproof GNSS tracker that features up to 1-year standby time
powered by internal batteries and supports wireless charging. The device is ideal for asset
monitoring & lot management that require tamper detection & temperature monitoring.
GL521MG supports LTE Cat M1/NB2 network on multiple bands for operation in America,
Europe, and Oceania with a fallback to GPRS.
1.1. GL521MG Product
Table 1. GL521MG Product
Model No.
Region
Technology
LTE Category
Operating Band
GL521MG
Global
GSM/LTE
eMTC/NB-IoT
GSM850/GSM900/DCS1800/PCS1900
LTE-FDD:
B1/B2/B3/B4/B5/B8/B12/B13/B18/B19/
B20/B25/B26/B27/B28/B66/B85
LTE-FDD:
B1/B2/B3/B4/B5/B8/B12/B13/B18/B19/
B20/B25/B28/B66/B71/B85
1.2. Reference
Table 2. GL521MG Protocol Reference
SN
Document Name
Remark
[1]
GL521M Series @Track Air
Interface Protocol
The air interface protocol between GL521MG and
backend server
1.3. Terms and Abbreviations
Table 3. GL521MG Terms and Abbreviations
Abbreviation
Description
RXD
Receive Data
TXD
Transmit Data
GND
Ground

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QSZTRACGL521MGUM0100 3
2. Product Overview
2.1. Product Appearance
Figure 1. GL521MG Product View
2.2. Key Description
Table 4. GL521MG Key Description
Key Functions
To power on: Long press for more than 3 seconds
To check the device status: Press the key for one time
To power off (needs to be configured): Long press for more than 3s after
power on
Light Alarm Sensor
Key
LEDs
Light Tamper Sensor

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2.3. LED Description
Figure 2. GL521MG LEDs
There are two LEDs on GL521MG. They can work separately and in combination to indicate the
status of the device. For the details when they work separately, please see the table below:
Table 5. GL521MG LED Description (work separately)
Fast flash: 100ms on/200ms off
Slow flash: 200ms on/1000ms off
Note: The LEDs will be on about 5 minutes after power on. After that, they will always be off.
When they work in combination, the details are described as below:
Table 6. GL521MG LED Description (work in combination)
LED
Event
State
Status LED
(Green)
Searching network
Fast flash
The device has been registered on network
Slow flash
SIM is locked by PIN
Solid on
Network modem off
Solid off
GPS LED
(Blue)
GPS is in the process of fixing
Fast flash
GPS is on and GPS gets fix
Slow flash
GPS off
Solid off
During power on
Both the LEDs will be on to indicate the device is being
powered on.
When checking the device status
Both the LEDs will be on to indicate the device still
works.
During power off
Both the LEDs will flash simultaneously to indicate the
device is being powered off.
During charging
Both the LEDs will flash simultaneously to indicate the
device is being charged.
When fully-charged
Both the LEDs will be solid on to indicate the device is
fully charged.
LEDs

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2.4. Parts List
Table 7. GL521MG Parts List
Name
Picture
Description
GL521MG Locater
EGPRS/LTE Cat-M1/LTE
Cat-NB2/GNSS Tracker
GL521MG Back Glue
Used to install GL521MG
GL521MG Magnetic Case
(Optional)
Used to install GL521MG
on metal surface for
convenient taking off
GL521MG Plastic Bracket
(Optional)
Used to hold GL521MG
Series on plastics bracket
which is installed on
surfaces where screw
holes can be drilled
GL521MG Data Cable
(Optional)
USB data cable which
can be used for firmware
upgrade and
configuration
GL521MG Wireless
Charger Accessory Kit
For battery charging
Note: Remove the
magnetic case when
charging the device with
the wireless charger kit

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QSZTRACGL521MGUM0100 6
3. Interface Definition
GL521MG has an internal 4-pin connector. It can be used to configure the device. The definition
of the pins is in the following table.
Figure 3. 4-pin Connector of the GL521MG
Table 8. Description of 4-pin Connections
Index
Pin Name
Description
1
USB_5V
Not used
2
RXD
MCU UART RXD
3
TXD
MCU UART TXD
4
GND
Power and digital ground

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4. Getting Started
4.1. Opening and Closing the Case
Figure 4. GL521MG Screw Position
To open/close the case: Unfasten or tighten the 4 screws at backside.
4.2. Turning on/off the Device
Figure 5. GL521MG Power Key
To turn on: Long press the key for more than 3 seconds.
To turn off (needs to be configured): Long press for more than 3s after power on.
Power Key