Graphtec America GL840-M - Isolated/Universal Input, Standalone Multi-Channel Datalogger
GL840 expands to two models for application specific use
- GL840-M Multi-Inputs Model
Suitable for temperature measurement in multiple channels
- GL840-WV Withstand-Voltage Model
Suitable for voltage measurement in battery pack or high-precision temperature measurements.
Wireless measurement using wireless LAN (option)
Wireless LAN option enables the wireless communication with other device. When the GL840 is set as a station, PC and smart devices will be able to access the WLAN unit directly.
Various functions, such as a bar chart data display, alarm output function, navigation function, and networking features, are available in the GL840 to assist be conveniently used.
Built-in 4GB Flash Memory with SD Card Support
The new GL series enables reliable long term measurment with its built-in 4GB flash memory and SD card slot for external storage devices.
* The built-in Flash memory is available for units with the following serial numbers, please contact your local representative for the details.
Three Types of Input Systems Enable Measurement of Various Signals
Along with the basic analog signal, Logic/Pulse, and digital sensors can be all connected to monitor a variety of measurements.
Combining GL100-WL and GL840
GL100-WL can now be connected to the GL840 as a remote sensor using the WLAN feature. GL840 supports up to five units of the GL100-WL.
Maximum Sampling Interval up to 10ms
Provides faster sampling rate 10ms for voltage measurement.
Three types of input system enable to measure various phenomena
Input system 1 : Multifunction analog input ports
Contains a highly isolated input system which ensures that signals are not corrupted by noise from other channels. The GL840's inputs are suitable for combined measurements from voltage, temperature, humidity, logic, and pulse signals.
The standard configuration has 20 analog input channels. It is expandable to 200 channels by adding optional 20 channels extension terminal base unit (B-566) and input terminal units (B-564 or B-565).
|Withstand voltage & Accuracy||Multi-input type (B-564)||Withstand-voltage type (B-565)|
|Voltage||Input voltage range||20 mV to 100 V||20 mV to 100 V|
|Max. voltage (Input - GND)||60 Vp-p||300 Vp-p|
|Temp.||Thermocouple||R, S, B, K, E, T, J, N, W (WRe5-26)|
|RTD (Resistance Temp. Detector)||Pt100 (IEC751), Pt1000 (IEC751), JPt100 (JIS)|
|Accuracy||Voltage||± 0.1% of F.S.||± (0.05% of FS + 10μV)|
|Temperature*||± 1.55 ºC||± 1.1 ºC|
* Accuracy rating for K-type thermocouple at 100˚C includes reference junction compensation. Accuracy varies by temperature levels and thermocouple types.
The following shows how a standard configuration is expanded to more than 40 channels
Configuration for additional channels
Number of channels
GL840 unit (GL840-M or GL840-WV)
Connection cable (B-567-05 or -20)
Terminal base (B-566)
Input terminal (B-564 or B-565 )
Offers longer cable for the input terminals
Input terminal blocks can be connected directly (in daisy chain), or using the B-565 cable(s). This allows the input terminals to be placed in separate locations according to the need of the application.
The input terminal unit and the GL840 main body can be extended by using an extended connections cable.
*If the signal is affected by noise, it may be required to use a slower sampling.
Input system 2 : Support digital sensors
Digital sensors and input terminal/adapters for the GL100 connects to the GL840 directly
Input system 3 : 4 channels of Logic/Pulse inputs
Supports 4-channels logic or pulse signal inputs. Pulse mode allows cumulative, instant, or rotational values for industrial measurement capability with speed and flow.
Maximum sampling interval of up to 10ms
Provides faster sampling rates for voltage measurements. Up to 10ms sampling speed is achievable when limiting the number of channels in use.
|Sampling Interval||Number of channels||Measuring|
Built-in 4GB Flash memory with SD card support
The new GL series enables reliable long term measurment with its built-in 4GB flash memory and SD card slot for external storage devices. The SD card slot supports an SDHC memory card of up to 32GB.
The captured data can be stored in GBD (Graphtec binary data) or CSV file format.
Capturing time* (when all 20 analog channels are being used with Logic/Pulse inputs turned off.)
|Sampling||GBD format||CSV format|
|10ms||31 days||3 days|
|50ms||77 days||11 days|
|100ms||95 days||16 days|
|200ms||108 days||21 days|
|500ms||270 days||54 days|
|1s||Over 365||109 days|
|10s||Over 365||Over 365|
*Figures are approximate. File size of captured data is 2GB in GBD or CSV file format on this chart.
Sampling interval is limited by the number of channels in use. (10ms:1ch, 50ms:5ch, 100ms:10ch)
Limited sampling speed is available when digital sensors and GL100-WL are used as a remote monitoring device.
Ring Capture Function
The most recent data is saved when the memory is configured in ring memory mode. (Number of capturing data is 1000 to 2000000 points)
Relay Capture Function
Data is continuously saved to multiple files up to 2GB without losing any data until capturing is stopped when the memory is configured in the relay mode.
Hot-Swapping the SD Memory Card
SD card can be replaced during data capturing when the sampling interval is 100ms or slower.
Displays the data by a bar chart (in firmware ver.1.10 or later)
The integrated data that is measured by the digital sensors can be displayed by a bar chart in the GL840 series.
|Available GS sensors||Measurement||Unit|
|GS-TH (Temp/Humidity) sensor||Integrated temperature||℃h|
|GS-DPA-AC adapter with GS-Acxxx sensor (AC current/power)||Integrated power||kWh|
|GS-LXUV (Illuminance/UV) sensor||Integrated illuminance||lxh or klxh|
Alarm Output Function
Alarm signals can be placed using the four channel alarm output ports based on set conditions for each channel.
* Optional cable (B-513) is required.
USB Drive Mode
USB drive mode function enables data to be transferred to the PC from GL840 by drag & drop feature.
Simple to use navigation screen allows setting operation for measurement and wireless LAN adapter.
Large Easy-to-Read 7-Inch Wide Color LCD
Monitoring data can be displayed in waveform or digital form. Parameter settings can be displayed on the screen.
3 Types of Power Source
Choose from AC power supply, DC supply* or the rechargeable battery pack.*
Various functions are available using a network.
GL840 Main Unit Specifications
|Number of analog input channels||20 channels in standard configuration, Expandable up to 200 channels|
|Number of analog input terminals||Up to 10 terminals (20 channels / terminal), standard config: 1|
|Type of analog input terminal||Multi-input type, Withstand-voltage type|
|Port for digital sensor||1 port for the sensor/input terminal/adapter of the GL100|
output *1(Input *2)
|Trigger or Sampling (1 channel), Logic/Pulse (4 channels)|
output *1 (Output *3)
|Alarm (4 channels)|
|Sampling interval||10 ms to 1 hour (10ms to 50ms: voltage only) *4, External signal|
|Time scale of waveform display||1 sec. to 24 hour /division|
Alarm function (Trigger action)
|Start or stop capturing data by the trigger|
Alarm function (Repeat action)
|Off, On (auto rearmed)|
Alarm function (Trigger source)
|Start: Off, Measured signal, Alarm, External, Clock, Week or Time
Stop: Off, Measured signal, Alarm, External, Clock, Week or Time
Alarm function (Condition Setting)
|Combination: OR or AND
Analog signal: Rising (High), Falling (Low), Window-in, Window-out
Logic signal: Pattern (combination of each input signal in high or low)
Pulse (number of count): Rising (High), Falling (Low), Window-in, Window-out
Alarm function (Alarm output)
|Outputs a signal when alarm condition occurs in the input signal *5|
function - Rotation count
|Counts the number of pulses per sampling interval and converts to rpm
(rotations per minute), Number of pulses for one rotation can be set to
50, 500, 5000, 50k, 500k, 5M, 50M, 500M rpm/F.S. (rpm./Full Scale)
function - Accumulating
|Accumulates the number of pulses from the start of measurement
50, 500, 5000, 50k, 500k, 5M, 50M, 500M C/F.S. (Counts/Full Scale)
function - Instant count
|Counts the number of pulses per sampling interval
50, 500, 5000, 50k, 500k, 5M, 50M, 500M C/F.S. (Counts/Full Scale)
function - Between channels
|Addition, Subtraction, Multiplication, and Division for analog input|
function - Statistical
|Select two calculations from Average, Peak, Maximum, Minimum, RMS|
|Search function||Search for analog signal levels, values of logic or pulse or alarm point
in captured data
|Interface to PC||Ethernet (10 BASE-T/100 BASE-TX), USB (Hi-speed), WLAN (using B-568 option)|
device - Internal
|Built-in 4GB Flash Memory *6|
device - External
|One SD card slot (Support SDHC memory card, up to 32GB) *7|
device - Saved contents
|Captured data, Setting conditions, Screen copy|
|Capturing mode||Mode: Normal, Ring, Relay
Ring: Saves most recent data (Number of capturing data: 1000 to 2000000 points) *8
Relay: Saves data to multiple files without losing data until dada capturing is stopped
|Replay data||Replays captured data that was saved in the GL840 (in GBD or CSV format)|
|Scaling (Engineering unit) function||Measured value can be converted to specified engineering unit
• Analog voltage: Converts using four reference points (gain, offset)
• Temperature: Converts using two reference points (offset)
• Pulse count: Converts using two reference points (gain)
|Action during data capture||• Displaying past data (using dual display mode (Current + Past data))
• Hot-swapping the SD memory card
• Saving data in between cursors
|Display Size||7-inch TFT color LCD (WVGA: 800 x 480 dots)|
|Display Language||English, French, German, Chinese, Korean, Russian, Spanish, Japanese|
|Display Information *9||Waveform in Y-T with digital values, Waveform only, Digital value, Digital values
and statistics values
|Operating environment||0 to 45 ºC, 5 to 85 % RH (non condensed)
(When operating with battery pack 0 to 40 ºC, charging battery 15 to 35 ºC)
|Power source - AC adapter||100 to 240 V AC, 50/60 Hz (1 pc of adapter is attached as standard accessory)|
|Power source - DC power||8.5 to 24 V DC (DC drive cable (option B-514) is required)|
|Power source - Battery pack||Mountable two battery packs (battery pack (option B-569): 7.2V DC, 2900mAh)|
|Power consumption *10||Max. 38 VA|
|External dimensions (W x D x H
in mm, Excluding projections)
|Approx. 240 x 158 x 52.5|
|Weight *11||Approx. 1010 g|
*1 Input/Output cable for GL (option B-513) is required to connect the signal.
*2 Input signal;
- Voltage range: Up to 24V (common ground)
- Signal type: Voltage, Open collector, Contact (relay)
- Threshold: Approx. + 2.5 V (Hysteresis: Approx. 0.5V (2.5V to 3V))
*3 Output signal: Open collector (pull-up to 5V by 10kΩ resistor)
- Voltage: Max. 30V
- Current: Max. 0.5A
- Collector dissipation: Max. 0.2W
*4 Minimum interval varies by number of channels used.
*5 Output port can be specified in each input channel.
*6 The built-in Flash memory is available for units with serial numbers C604XXXX or later. Please contact your local representative for more information.
*7 SD memory card cannot be used on the SD card slot while the wireless LAN unit (opton B-568) is used.
*8 Size of the capture data will be limited to 1/3 of available memory.
*9 Display mode is switched every time the dedicated key is pressed. In magnified digital value mode, the
displayed channel number can be specified. In the waveform display mode, the changing of the time scale will
be effective from the point of the next displayed data.
*10 Rating under maximum power consumption using the AC adapter, with LCD display on, and battery pack(s)
*11 Excludes AC adapter and battery pack.
Software Specifications for PC
|Supported OS||Windows 10, 8.1, 8, 7, Vista (32/64-bit edition)|
|Supported device||GL840 (USB, Ethernet, WLAN), GL100 (USB, WLAN)|
|Functions||Control the GL series, Real-time data capture, Replay data, and Data format conversion|
|Supported units & channels||Up to 1000 channels total, Up to 4 groups (number of units is limited by model)|
|Settings control||Input condition, Capturing condition, Trigger/Alarm condition, Report, etc.|
|Capturing - data Saved to PC||Saves captured data in real time (in GBD binary or CSV format)|
|Capturing data - Saved to GL unit||Saves to the SD memory card (in GBD binary or CSV format)|
|Displayed information||Y-T waveform, Digital values, Report, X-Y graph (specified period of data, data
reply only), Two displays for the current and past data, and Statistical calculation
|File operation||Converting data format to CSV from GBD binary, merge multiple data files
in the time axis or as an additional channel
|Warning function||Send e-mail to the specified address when the alarms occur|
|Statistical calculation||Maximum, Minimum, and Avarage during data capturing|
|Report function||Creates the daily or monthly report automatically|
Software specifications for Smart device
|Supported OS||Android 4.1 to 6.0, iOS 7/8/9 (up to 9.3.4)|
|Supported device||GL840 (WLAN), GL100 (WLAN)|
|Functions||Control the GL series, Display measured data in waveform or digital value|
|Supported units||Up to 10 units|
|Settings control||Start/Stop, Sampling interval|
|Capturing data||Saves captured data in the GL main body (data cannot be saved in the smart device)|
|Displayed information||Data captured in real time by digital value, Replay the data stored in the GL body by the waveform|
Wireless LAN Unit (option) Specifications
|Communication method||Wireless communication (using radio waves in the 2.4GHz band)|
|Supported WLAN system||IEEE802.11b/g/n
WPS: Push button or PIN method
Security protocols: WEP64, WEP128, WPA-PSK/WPA2-PSK, AKIP/AES
Communication distance: Approx. 40m (depending on the conditions of radio
|Installed location||Attaches to the SD card slot *7|
|Function||Access Point mode: Communicate with the GL100-WL as a remote sensor
(captured data in the GL100-WL is transferred to GL840)
Station mode: Communicate with PC or Smart device (control GL840 and
transfer the data from GL840)
|Connected number of GL100-WL||GL840: Up to 5 units of the GL100-WL|
GL840 Analog Input Specifications
|Input method||All channels isolated balanced input *12, Scans channels for sampling|
|Type of input terminal||Screw terminal (M3 screw)|
|Measurement range (Voltage)||20, 50, 100, 200, 500 mV, 1, 2, 5, 10, 20, 50, 100 V, and 1-5V F.S. (Full Scale)|
|Measurement range (Thermocouple)||Type: K, J, E, T, R, S, B, N, W (WRe5-26)
Range: 100, 500, 2000 ºC *13
|Measurement range (RTD - Resistance Temperature Detector)||Type: Pt100, Pt1000 (IEC751), JPt100 (JIS)
Range: 100, 500, 2000 ºC *13
|Measurement range (Humidity)||0 to 100 % RH - using the humidity sensor (option B-530)|
|Filter||Off, 2, 5, 10, 20, 40 (moving average in selected number)|
|Voltage||± 0.1% of F.S. (Full Scale)|
(TS: Temp Sense)
|R||0 ≤ TS ≤ 100 ºC||± 5.2 ºC|
|100 < TS ≤ 300 ºC||± 3.0 ºC|
|300 < TS ≤ 1600 ºC||± (0.05% of rdg. + 2.0 ºC)|
|S||0 ≤ TS ≤ 100 ºC||± 5.2 ºC|
|100 < TS ≤ 300 ºC||± 3.0 ºC|
|300 < TS ≤ 1760 ºC||± (0.05% of rdg. + 2.0 ºC)|
|B||400 ≤ TS ≤ 600 ºC||± 3.5 ºC|
|600 < TS ≤ 1820 ºC||± (0.05% of rdg. + 2.0 ºC)|
|K||-200 ≤ TS ≤ -100 ºC||± (0.05% of rdg. + 2.0 ºC)|
|-100 < TS ≤ 1370 ºC||± (0.05% of rdg. + 1.0 ºC)|
|E||-200 ≤ TS ≤ -100 ºC||± (0.05% of rdg. + 2.0 ºC)|
|-100 < TS ≤ 800 ºC||± (0.05% of rdg. + 1.0 ºC)|
|T||-200 ≤ TS ≤ -100 ºC||± (0.1% of rdg. + 1.5 ºC)|
|-100 < TS ≤ 400 ºC||± (0.1% of rdg. + 0.5 ºC)|
|J||-200 ≤ TS ≤ -100 ºC||± 2.7 ºC|
|-100 < TS ≤ 100 ºC||± 1.7 ºC|
|100 < TS ≤ 1100 ºC||± (0.05% of rdg. + 1.0 ºC)|
|N||-200 ≤ TS < 0 ºC||± (0.1% of rdg. + 2.0 ºC)|
|0 ≤ TS ≤ 1300 ºC||± (0.1% of rdg. + 1.0 ºC)|
|W||0 ≤ TS ≤ 2000 ºC||± (0.1% of rdg. + 1.5 ºC)|
|R.J.C||± 0.5 ºC|
(TS: Temp Sense)
|Pt100||-200 ≤ TS ≤ 100 ºC||± 1.0 ºC|
|100 < TS ≤ 500 ºC||± 1.0 ºC|
|500 < TS ≤ 850 ºC||± 1.0 ºC|
|Pt1000||-200 ≤ TS ≤ 100 ºC||± 0.8 ºC|
|100 < TS ≤ 500 ºC||± 0.8 ºC|
|JPt100||-200 ≤ TS ≤ 100 ºC||± 0.8 ºC|
|100 < TS ≤ 500 ºC||± 0.8 ºC|
General GL840 Analog Input Specifications
|A/D converter||Sigma-Delta type, 16 bits (effective resolution: 1/40000 of the measuring full range)|
|Input resistance||1MΩ ±5%|
|Allowable signal source resistance||Up to 300Ω|
|Maximum input voltage - Between (+) / (-) terminal||20 mV to 2 V range: 60 Vp-p, 5 V to 100 V range: 110 Vp-p|
|Maximum input voltage - Channels ((-) / (-))||60 Vp-p|
|Maximum input voltage - Channel / GND||60 Vp-p|
|Max. voltage (withstand) - Between channels||350 Vp-p (1 minute)|
|Max. voltage (withstand) - Channel / GND||350 Vp-p (1 minute)|
*12 The terminal "b" for using the RTD is connected each other across all channels.
*13 If the specifications of the temperature sensor is lesser or greater than the selected measurement range, GL840
can measure up to the specifications of the sensor.
*14 Subject to the following conditions:
- Room temperature is 23 oC ± 5 oC.
- When 30 minutes or more have elapsed after power has turned on.
- Filter is set to 10.
- Sampling rate is set to 1 sec, using 20-channel in GL840-M and 10-channel in GL840-WV.
- GND terminal is connected to ground.
*15 Wire size of thermocouple used is 0.32mm diameter in the T or K type and 0.65mm diameter in other types.
*16 Supports 3-wire type sensor.
Options and Accessories
|Input terminal (Multi-inputs)||B-564||20ch input terminal, multi-input type|
|Input terminal (Withstand voltage||B-565||20ch input terminal, withstand-high-voltage type|
|Base unit for input terminal||B-566||Base unit for input terminal (B-564 or 566)|
for extension terminal
|B-567-05||Cable to connect GL840 and B-566, 50 cm long|
|B-567-20||Cable to connect GL840 and B-566, 2 m long|
|Wireless LAN unit||B-568||WLAN adapter, IEEE802.11 b / g / n|
|Battery pack||B-569||Rechargeable Lithium-ion battery (7.2 V, 2900mAh)|
|Bracket for DIN rale (GL840 main body)||B-570||Bracket for DIN rail (GL840 main body), Build-to-order|
|Bracket for DIN rail (extension terminal)||B-540||Bracket for DIN rail (Input terminal), Build-to-order|
|Input/Output cable for GL series||B-513||2 m long (no clip on end of cable)|
|DC drive cable||B-514||2 m long (no clip on end of cable)|
|Humidity sensor||B-530||With 3 m long signal cable (with power plug)|
|Shunt resistor||B-551-10||250 ohms 0.1% (it converts the signal to the "1-5V" from the "4-20mA")|
|AC power adapter||ACADP-20||Input: 100 to 240 V AC, Output: 24 V DC|
|Temp & Humidity sensor||GS-TH||Temperature and humidity measurement|
|Illuminance & UV sensor||GS-LXUV||Illuminance and UV intensity measurement, cable 20cm long|
|Carbon Dioxide (CO2) sensor||GS-CO2||CO2 measurement, cable 20cm long|
|Acceleration & Temp sensor||GS-3AT||Acceleration and temperature measurement, cable 20cm long|
|Thermistor input terminal||GS-4TSR||Temp measurement (using a Thermistor), cable 20cm long|
|Thermistor sensor (Normal type)||GS-103AT-4P||Temperature sensor (-40 to 105 ºC), 3m long, 4pcs/set|
|Thermistor sensor (Ultrathin type)||GS-103JT-4P||Temperature sensor (-40 to 120 ºC), 3m long, 4pcs/set|
|AC current sensor adapter||GS-DPA-AC||Current measurement (using a CT), cable 20cm long|
|AC current sensor (50A)||GS-AC50A||Current sensor (CT) 50A, cable 20cm long|
|AC current sensor (100A)||GS-AC100A||Current sensor (CT) 100A, cable 20cm long|
|AC current sensor (200A)||GS-AC200A||Current sensor (CT) 200A, cable 20cm long|
|Voltage & Temp input terminal||GS-4VT||Voltage or Temperature (using a thermocouple), cable 20cm long|
|Module extension cable||GS-EXC||Extension cable for the sensor / terminal / adapter module, 1.5m long|
|Dual port adapter||GS-DPA||Connect up to 2 sensor modules|
Do you have a Isolated/Universal Input, Standalone Multi-Channel Datalogger that needs to be calibrated?
We offer standard traceable calibration and ISO 17025 accredited calibration services.Get your Isolated/Universal Input, Standalone Multi-Channel Datalogger calibrated today! Click Here!