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Firmware for GL840 series download

Software License Agreement

It is required to review the following license agreement before the software is downloaded. We will be deemed that the customer has to agree to the terms and conditions of the license agreement when the software had been downloaded by the customer. Please note that it is not possible to download or use the software if the customer does not agree to it.

Downloading Files

Ver.1.64 (Latest version)

Date of updated23 Mar, 2023
Supported ProductsGL840
Downloading filesSoftwareGL840_FU(V164).zip (4,272KB)
Software (*1)GL840_PTN_V110.zip (2,958KB)
  1. When updating the firmware from Ver1.60 or earlier, download GL840_PTN_V110.zip and update it.
    Unzip GL840_FU (V164) .zip and GL840_PTN_V110.zip, and update in the following steps.
    1. MainVer164Rev0001A00.GL840
    2. PatternVer110Rev0001A00.GL840.

Revision History


  1. Fixed the problem that the data values in CSV file format may become abnormal when saving the data in GBD file format with the save data between cursors function, and then save the data in CSV file format when playing back recorded data in GBD file format.
  2. Fixed the problem that the time of the main unit is set to an incorrect time in rare cases when using the network time setting function.
  3. Fixed the problem that waveforms are displayed with undefined values when playing back CSV files that were finished with the conversion rate increased in the scaling settings.


  1. Communication enhancement in the event of DoS attacks or other unauthorized access to the web server function when the main unit is connected to an externally accessible Internet line.
  2. Fixed the problem that the subsequent connection becomes unstable when a large number of connections overlap on a line with slow network speed.


  1. Fixed the problem that e-mail may not be sent correctly when the e-mail sending function with a wireless LAN connection using the B-568 (GL wireless LAN unit) or a slow communication line.
  2. Fixed the problem that the backup process after recording is stopped when the main unit becomes remote mode by communication from the control software (GL100_240_840-APS or GL-Connection) while the main unit is in recording operation under the following conditions.
    1) The stop side source setting is other than off in the trigger setting.
    2) Repeat recording function is on.
    3) Backup functions is enabled.
    4) Recording must be started from the main unit, not from the control software.
  3. Corrected Korean massage display when replacing SD card during recording.
  • Please download and update GL840_PTN_V110.zip when updating from Ver. 1.60 or later.
    Unzip GL840_V162.zip and GL840_PTN_V110.zip,
    Then after unzip MainVer162Rev0001A00.GL840,
    please unzip, PatternVer110Rev0001A00.GL840


  1. Fixed the problem that a disk error occurs when the same file is played again, if the playback is finished with the cursor position is at the last point while a file recorded in CSV format is played.
  • Please download and update GL840_PTN_V110.zip before when updating from Ver. 1.60 or later.
    Unzip GL840_V161.zip and GL840_PTN_V110.zip,
    Then after unzip 1. MainVer161Rev0001A00.GL840,
    please unzip, 2. PatternVer110Rev0001A00.GL840


  1. Support connection of the new midi LOGGER GLT400.
  • There are two update files in Ver 1.60.
    Unzip GL840_V160.zip and GL840_PTN_V110.zip,
    Then after unzip 1. MainVer160Rev0001A00.GL840,
    please unzip, 2. PatternVer110Rev0001A00.GL840.


  1. Added description of C-type thermocouple to thermocouple TC-W.
  2. Fixed the problem that logic triggers were not set correctly when saving and loading settings.


  1. Reduced file loading time at startup.
  2. Email designated time notation in English changed from “Interval” to “Time”.
  3. Changed so that processing cannot continue if SD card is not inserted when backup side SD card is replacement.


  1. Fixed the problem that it will be displayed as ++++++ during “Playback for recording (2 screens)”. if the data recorded in CSV format exceeds the measurement temperature of 200°C, when the input setting is temperature and the range is set to 500°C.


  1. Fixed the problem that unable to log in some client software when accessing the FTP server of the main unit.
  2. Fixed the problem that the data transfer function may not work after repeated communication disconnections during data transfer from the control software.


  1. Support connection to thermal printers.
  2. Fixed the problem that data downloading, and some web server functions would not work properly if data downloading failed repeatedly when connected to a network with poor communication environment.
  3. Fixed the problem that data may be out of time when data loss occurs during receiving real-time data with PC software.


  1. Added the function allowing long-term recording without using full storage media by deleting recorded files upon successful FTP backup.
  2. Added switch files by capacity and recording time function to Relay capture function.
  3. Support sending e-mail to e-mail servers that require certificates, such as Office365.


  1. Added a check-sum function for recorded files.
  2. Fixed the problem that the CSV file extension may not be CSV if the file name is blank when saving the CSV file in the result of the statistical calculation between cursor.


  1. Fixed the problem that communication sometime stopped when receiving a large number of packets at once on a wired LAN.


  1. Supported connection to the remote monitoring system, GRM-ONE Series.


  1. Added backup function in CSV file format recording.


  1. Added units for the US in the scaling function.
  2. Fixed the problem that OS system down would be caused when sending many interface commands “:MEAS:OUTP:ORDER?”.
  3. Changed some strings in the German display menu.
  4. Fixed the problem that communication becomes unstable if commands are sent to GL one character at a time when the line feed code setting is CR+LF in USB connection communication.


  1. Fixed the problem that the measured value of the GL100 sensor will be locked after several hours when the battery pack is not installed and the sampling rate is set faster than 1 second, if the GL100 sensor (AC, LX-UV, 4VT, 4TSR) is connected to the GL840 main unit.


  1. Improved the so that the connection can be restored more stably by fixing in reconnection process when the connection is rarely lost during wireless connection with GL100.


  1. Improved stability of temperature measurement where room with a large temperature gap by speeding up the interval time for room temperature compensation,


  1. Fixed the problem that the saved data during playback might not be saved with correct values depending on conditions such as sampling and recording time, when CSV data was saved during 2-screen playback for CSV recording,


  1. Fixed the problem that the file name does not switch and overwrites the same file in Relay capture function.
    (This bug occurs only in Ver. 1.24)


  1. Fixed the problem that settings could not be saved to SD2. (Previously stored in SD1.)
  2. Corrected a typo in the “Ring/Relay capture” text in the Chinese menu
  3. Fixed the problem in which communication stops when the receive buffer runs out when using a slow throughput line for LAN communication.


  1. Fixed the problem that a large error was occurred in the value when displaying in Fahrenheit with Pt100/JPt100.


  1. Improved processing when an error occurs during wireless LAN connection with GL100-WL.


  1. Support PC software GL-Connection.
    *Please update to Ver. 1.21 or later to connect GL-Connection.
    *GL-Connection requires Ver. 1.80 or later.
    The latest version of GL-Connection can be downloaded from this website.


  1. Changed some Spanish translations.


  1. Fixed the problem that rarely stop transferring halfway through when transfer of large files via FTP transfer.
  2. Fixed the problem that the lower limit is not set correctly when setting alarms and triggers from the IF command when the temperature range is 500 or 100°C.
  3. Fixed the problem that the web display does not work when accessed by a host name registered with DDNS as a URL in the website.
  4. Fixed the problem that it took a long time to display correct temperature values when power was turned on with multi-CH and slow sampling settings.


  1. Fixed the problem that only counted for 30 seconds, and the instantaneous value of the main unit pulse was reset every 30 seconds when sampling speed was slower than 30 seconds.
  2. Fixed the problem that the URL of the FTP server was returned with the network address of the wired LAN when accessed via FTP on the Web server from a wireless LAN.
  3. Improved network restart time.


  1. Added the Integral bar graph display function.
    * please refer to the user manual (GL840-UM-102) for more details.
    GL840-UM-102 can be downloaded from this website.
  2. Added Chrome, Safari, and Opera to the list of supported browsers for The Web server function.
  3. Fixed the problem that the set value became 1/10 of the original value when the span, trigger level, and alarm level of integrated CH were set by I/F commands.
  4. Reduced the error in measurement values caused by adding a light source selection function which previously caused error to the illuminance measurement value by the light source environment when using the illuminance UV sensor (GS-LXUV).
    * Only reconditioned illuminance UV sensor (GS-LXUV) is available for this function.
    Reconditioned GS-LXUV has a blue “●” sticker next to the serial number.


  1. Initial version