GASTRON GPD-100 User manual

Design, Develop, Manufacture, Install and Maintenance Service for Gas Leak Alarm
DOC NO.GT-046IM00E
GPD-100
Instruction Manual
Revision: 1.2
Copyright ⒞GASTRON, Co., LTD. All rights reserved.
For proper use, please read this manual carefully prior to
use

GPD-100 Instruction Manual
PAGE 2 of 29
Rev 1.2(2021.09.29)
Thank you for purchasing our GASTRON’s product.
Gastron is a specialized company in producing gas detector and gas monitoring system.
We have been recognized by customers for our best quality products and excellence in easy-to-
use design. We are striving to provide the suitable product that fits customer’s needs, and
continuously put every effort to develop better gas detector to satisfy customer’s requirements.
From now on, we will be your reliable partner to shed a bright light on your concern about gas
detector. Please contact us if you have any question. You can obtain best solution from us with
great satisfaction.
This instruction manual describes how to operate the gas detector. It also briefly explains how
to repair and maintain the device. Please keep this manual in safe place after reading carefully.
This instruction manual will be of great help when you encounter any trouble or question while
you are using the device. (Instruction Manual Rev 1.2 is suitable for program version V.1.10.
Please refer to Instruction Manual Rev 1.1 up to program version V.1.01.)
If you have any problem when using our product, contact us to following address:
Address: 23, Gunpocheomdansaneop 1-ro, Gunpo City, Gyeonggi-do, KOREA
Tel : [phone]
Fax : [phone]
URL : www.gastron.com
E-mail : [e-mail]
Note
•For accurate operation of the gas detector, check and calibrate at least
once every 6 months.
(* KOSHA GUIDE : P-166-2020 / refer to 7 Calibration & maintenance No. 7.1)
• We recommend that the gas detector should be inspected and calibrated with
calibration gas prior to use for accurate operation.
•Without getting calibrated, the device might be malfunctioned due to sensor
aging problem.
•When it is necessary to disassemble the device, technician with special skills
for a gas detector must perform it.
•For more details about maintenance and calibration of gas detector, contact
our technical department via email or visiting our web site.
GASTRON reserves the right to change published specifications and designs without prior notice.
※KOSHA GUIDE : P-166-2020
→Calibration should be performed at the cycle recommended by the manufacturer. If there is
no specific calibration cycle, it should be carried out quarterly.

GPD-100 Instruction Manual
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TABLE OF CONTENTS
1. Introduction......................................................................................................................5
2. Structure ..........................................................................................................................5
3. Specification .....................................................................................................................6
3.1. General Specifications ................................................................................................6
3.2. Mechanical Specifications...........................................................................................6
3.3. Electrical Specifications (Standard Type)......................................................................6
3.4. Environmental Specifications ......................................................................................7
4. Name and Functional Description of Components..............................................................7
4.1. Composing Elements..................................................................................................7
4.2. Front Panel Display part..............................................................................................8
5. Operation .........................................................................................................................9
5.1. Connecting Sampling Probe .......................................................................................9
5.2. Power On ..................................................................................................................9
5.3. Gas Measurement Mode..........................................................................................10
5.4. Mode Configuration.................................................................................................10
5.5. Power Status............................................................................................................10
5.5.1. Power Status Details .......................................................................................11
5.6. How to use a log mode ............................................................................................11
5.6.1. Gas log file .....................................................................................................13
5.6.2. Report log file .................................................................................................13
6. System Mode..................................................................................................................15
6.1. Mode configuration .................................................................................................15
6.2. Detailed Mode description........................................................................................16
6.3. Configuration Mode.................................................................................................17
6.4. Program setting mode..............................................................................................18
6.5. Zero Calibration .......................................................................................................19
6.5.1. Auto Zero Calibration......................................................................................19
6.5.2. Manual Zero Calibration..................................................................................20
6.6. Span Calibration.......................................................................................................21
6.7. Alarm mode.............................................................................................................21
6.8. Log Save Mode ........................................................................................................23
6.8.1. Log Save Mode Setting ...................................................................................23
6.8.2. Log Save Mode Operation...............................................................................24
7. Troubleshooting..............................................................................................................25
7.1. Fault Code ...............................................................................................................25
7.1.1. Fault Alarm Clear ............................................................................................25
7.2. Warning Code..........................................................................................................26
7.3. Recovery List ............................................................................................................26

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8. Appearance and Dimensions ...........................................................................................28
9. Revision History...............................................................................................................29

GPD-100 Instruction Manual
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1. Introduction
The GPD-100 is a portable gas detector that has been developed to detect a variety of gases so
as to prevent serious accidents caused by unexpected gas leaks in hazardous areas such as
industrial plants, gas storage facilities and factories in the process of producing or consuming
combustible gases and toxic gases.
The portable gas detector GPD-100 continuously monitors the air for detecting dangerous gas
leaks and displays the measured value of gas concentration. It makes a visual signal and an
audible alarm when it detects gas leaks.
2. Structure
The body of GPD-100 is made of polycarbonate-ABS housing. A Diaphragm pump is equipped
inside the GPD-100. The sampling pump pulls the air containing leaked gas in the device.
The GPD-100 mainly consists of three parts as follows: (1) LED that presents the measured
value of gas concentration and shows alerts to the user at front panel, (2) Port that takes in and
releases gas, and (3) terminal that enables to connect USB, Micro SD card and DC jack. A sensor
is a removable cartridge type, so that it can be easily detached and replaced.
[Figure 1. GPD-100 Overview]

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3. Specification
3.1. General Specifications
I T E M S
S P E C I F I C A T I O N
Measuring Type
Auto Sampling type
Display Type
LED segment Type
Measuring Method
Electrochemical / Cartridge
Catalytic/ Cartridge
semiconductor / Cartridge
Photoionization detector(PID) / Cartridge
Detectible Gas
Flammable gas, Toxic gas, Oxygen (Note1)
Measuring Range
000.0 ~ 9999(Note1)
Accuracy
≤±3% / Full Range
Zero Drift
≤2% / Full Range
Response Time
Target gas response time may vary. Refer to the
sensor module datasheet or contact GASTRON for
specific sensor data.
Pump Type
Diaphragm Pump
Flow Rate
100 ~ 1,000 ml (Normal 300~500ml / min)
Gas Sample Line
5m ( 1/4" Tube )
Approvals Classification
CE ( No. K5004/E12 )
Storage
Micro SD Card
Warranty
Main Unit
2Year
Sensor
1Year
※Note1. Refer to the “List of detectable gases & vapours” or contact GASTRON for specific gas
3.2. Mechanical Specifications
I T E M S
S P E C I F I C A T I O N
Dimension / mm
208(W) × 95(H) × 100(D) mm
Weight including Sensor
App. 1.2kg
Sample gas vent / inlet
1/4" Teflon Tube
Body material
PC-ABS(polycarbonate-ABS)
3.3. Electrical Specifications (Standard Type)
I T E M S
S P E C I F I C A T I O N
Battery Type
Lithium-Ion 7.3 V / 5.5Ah
Charge Time
4 Hours
Operating Time
Normal Sensor Type
10 Hours
CEC Sensor Type
5 Hours
Charge Voltage
(DC Adaptor Output Voltage)
DC 12V /2A
DC Adaptor Input Voltage
AC100~230V 50/60Hz

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3.4. Environmental Specifications
I T E M S
S P E C I F I C A T I O N
Operation Temperature
Main Unit
-20 to 50 ℃
Sensor
Sensor dependant, Refer to the
sensor module datasheet or contact
GASTRON for specific sensor data.
Storage Temperature
Main Unit
-20 to 50 ℃
Sensor
Sensor dependant, Refer to the
sensor module datasheet or contact
GASTRON for specific sensor data.
Operation Humidity
Main Unit
5 to 99% RH (Non-condensing)
Sensor
Sensor dependant, Refer to the
sensor module datasheet or
contact GASTRON for specific
sensor data.
Pressure Range
90 to 110KPa
Max. air velocity
6m/s
4. Name and Functional Description of Components
4.1. Composing Elements
[Figure 2. GPD-100 composing elements]

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4.2. Front Panel Display part
[Figure 3. Front panel display part]
No
Name
Descriptions
1
Calibration icon
Indicating that calibration procedure is being processed.
2
Setting icon
Indicating that value setting operation is being processed.
3
Pump Icon
Pump Operation Status display
4
Test Icon
Indicating that gas detector operates in test mode.
5
Time setting Icon
It turns on when internal time is being set.
6
Log Status Icon
It turns on when log save is being set.
7
DC Adaptor Icon
Indicating that DC adaptor connection status
8
Battery Icon
Indicating that Battery charging status
9
Measurement Unit
Indicating that current measuring unit presented on
screen.(PPB, PPM, %VOL, %LEL)
10
Flow Rate
When this icon appears, measured value of flow is indicated as
10 different levels, while in normal measuring state.
11
Communication
Icon
This icon is turned on, when USB communication is being used.
12
Lock Icon
Indicating device is in lock mode. Configuration mode is not
allowed.
13
Pyrolyzer Icon
Indicating that Pyrolyzer operation status
14
Trouble icon
It turns on when fault is detected
15
Alarm2 icon
Indicating that 2nd alarm is set or detected.
16
Alarm1 icon
Indicating that 1st alarm is set or detected.
17
Zero, Span icon
Indicating that zero or span mode is entered during calibration
18
Gas concentration
display
It is used for displaying measured value or message to the user

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19
Power LED
This Power LED is turned on when power is successfully
supplied.
20
Trouble LED
This Trouble LED is turned on when a device is recognized as
malfunctioned
21
Alarm LED
This Alarm1 LED is turned on, when the measured value of gas
concentration exceeds the preset value of Alarm1 level
22
Power Key
Power on /off control key
23
RUN / MODE Key
This key is used for changing setting mode or measuring mode.
24
AUTO ZERO Key
Auto Zero calibration key
25
Down Key
It is a key to decrease a setting value in function setting mode.
26
Up Key
It is a key to increase a setting value in function setting mode.
27
RESET key
In function setting mode, Reset Key is used for recovering the
device’s state back to menu state or standby state.
[Table 1. Front Display part description]
5. Operation
5.1. Connecting Sampling Probe
Connect a sampling Probe(1/4”Teflon tube) to a “GAS IN” port
Figure 4. Sampling Port Connection
5.2. Power On
Press power switch( ) and hold it more than 2 seconds. Then it starts up.
Power LED turns on and ‘LOAd’is displayed (during about 15 seconds) indicating sensor
data is being loaded. After ‘WaIt’is displayed, make sure that ‘Stby ’(stand by) shows up
blinking.
➢When you turn on the power switch, version information will show up
in LCD like “UX.XX”. Then “L0Ad”(Load) message flashes on and off
during about 15 seconds. Once warming-up is finished, “Stby”(Stand by)
message will come up, which indicates that the device is now ready to
measure. If the device detects a fault in device or sensor cartridge, a
faulty alarm occurs.

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5.3. Gas Measurement Mode
➢When you press a switch “RUN/MODE”, the device will count down from
20 to 1, which is the time duration necessary to allow the sensor to
stabilize. When it reaches to 0, the measured value of gas concentration
is displayed on LCD.
Note 1) In the occurrence of fault in sensor cartridge, error message
ranging from “E-10”to “E-31”flashes in LCD and also trouble LED turns
on. (Please refer to error and warning messages)
Note 2) In case where gas concentration value is greater than 10% of
specified high scale value, “OuEr”message flashes every half a second.
Note 3) Sensor stabilization time varies depending on the sensor type.
✓In case of combustible sensor : 10 seconds
✓In case of toxic sensor & O2 sensor : 20 seconds
5.4. Mode Configuration
5.5. Power Status
Item
Power Icon display
Description
Full charge
Full charge status. Outline of the battery icon
keeps blinking. Battery is not charged in this
state.
➢While the device displays ”Stby”(Stand by), press and hold “RUN/MODE”key
more than 2 seconds. Then you will enter menu selection mode.
➢Password entering screen shows up. Input password using “ ”Key or
“ ”Key. If you press “RUN/MODE” key after entering password, then you
enter a configuration menu (“ConF”)
Note 1) Password must be entered, “FAIL” is displayed when “RUN/MODE”
key is pressed in the initial password ([--]) status. Default password value :
[00]
➢Select “COnF”(configuration) using “ ” key or “ ” key and then press
“RUN/MODE”key. You will enter environment configuration mode.

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80%
charge
more than 80% of Battery level indicator
(The outer line of the battery does not blink)
60%
charge
more than 60% of Battery level indicator
(The outer line of the battery does not blink)
40%
charge
more than 40% of Battery level indicator
(The outer line of the battery does not blink)
20%
charge
more than 20% of Battery level indicator
(The outer line of the battery does not blink)
5% charge
Battery low message shows up in LCD and
battery icon keeps blinking.
charging
status
This icon keeps blinking when battery is being
charged. When DC adaptor is recognized after it
is inserted, this icon turns on.
[Table 2. Power Status description]
5.5.1. Power Status Details
5.6. How to use a log mode
When you want to read data stored in an external memory after operating the log mode,
connect the external memory to PC.
For the log saved on the Micro SD Card, a folder will be created according to the measured
date and time, and a text file is created according to the run status in the created folder.
You can see the folders named by date when the data has been stored. The date is
determined by the date you set in “tImE” mode. (04-17 folder of the figure below, displays
the April 17)
➢If the battery is less than 5%, a warning message “BatL”(Battery Low) will
be displayed. In the “BatL” status, it is not possible to enter the gas
measurement mode even if the “RUN/MODE” key is pressed.
➢If the battery is less than 3%, a warning message “PF-5”(Power-OFF) will be
displayed and the detector will be powered off automatically after 5
seconds count.

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[Figure 5. Date folders stored in SD card]
Inside the folder named by date, there are folders named by time(hour_min_sec) stored.
Each of these folders contains log data regarding measurement record and equipment
information. (04-17 folder of the figure below, displays the April 17)
[Figure 6. Time folders generated in date folder]
Three types of files are generated as log data in the hour_min_sec folder.
[Figure 7. Log data files saved in time folder]

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File
Name
Description
Gas Log File
GAS00.TXT
Log about gas measurement records
Report File
REPORT.TXT
Log about System Status and
Measurement Status
System File
INFO.DAT
System File
[Table 3. Log File description]
5.6.1. Gas log file
Gas log files are stored in GAS00.txt name, to open using Notepad or Text editor.
In the GAS00.TXT file, gas measurement log records are saved in unit of second.
GAS00.txt file is saved for up to 12 hours, and a new GAS01.txt file is created after 12
hours. (GAS00 →01 →02 →… →99, the files after GAS99.txt are overwritten with the
GAS00.txt file).
By using notepad, you can see the stored value as shown below figure.
[Figure 8. Gas Log File]
The contents of the Text log file have the meaning as described below table.
Item
Log Format
Contents
0:0:0
0.0
Description
Measurement Time(Second unit)
Gas Data
[Table 4. Gas Log description]
5.6.2. Report log file
Report files are stored in REPROT.txt name, to open using Notepad or Text editor.
REPORT file contains data as follows: measurement equipment type, equipment setting
status, senor and log related information.
By using notepad, you can see the stored value as shown below figure.

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[Figure 9. Report file status]
Item
sub time
Description
Note
Device
Device Name
Model name of the product
F/W Version
Firmware version number
Address
Address of the device
Flow Auto
Whether or not flow auto function is
under operation
Flow Level
Setting value of flow level
Pyrolyzer
Whether or not CEC is under
operation / CEC voltage setting
Displays voltage
setting only when
CEC is ON
Sensor
Gas
Measurement Gas type
Unit
Measurement unit
Range
Measurement range
Span Lev
Span level
Span Cal time
Time when span calibration has
been done
Alarm
Latch
Whether or not alarm latch mode is
under operation
Alarm1 direction
Output polarity for alarm1
Alarm1 Level
Criterion level for alarm1
Alarm2 direction
Output polarity for alarm2
Alarm2 Level
Criterion level for alarm2
Over Level
Over level of measurement

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Log
Auto
Whether or not auto saving is under
operation
Start
Time when logging starts
Stop
Time when logging starts
Sample period(sec)
Logging sampling period (seconds)
Record Number
The number of measurement
records
MIN
Minimum value
MAX
Maximum value
AVG
Average value
Event List
Total number of events occurred
[Table 5. Report file items description]
6. System Mode
6.1. Mode configuration
Menu structure of the device is as following table.
Item
Display
Description
Note
CONFIGURATION MODE
CONF
Configuration of internal function
PROGRAM MODE
PRGM
Configuration of related gas
measurement
CALIBRATION MODE
CALB
Calibration gas
ALARM MODE
ALAM
Configuration of Alarm setting
TIME MODE
TIME
Setting of Internal Time
Factory Mode
SENSOR DATA MODE
S-DT
Check of sensor data
Factory Mode
TEST MODE
TEST
Test Mode
Factory Mode
FLOW MODE
FLOW
Configuration of flow setting
Factory Mode
Log Mode
Log
Configuration of log function
MAINTENANCE MODE
M-T
Configuration of Maintenance setting
Factory Mode
[Table 6. Mode Configuration]

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6.2. Detailed Mode description
Detailed menu and sub-menu of the device is as following table
Level 1
Level 2
Level 3
COnF
Configurat
ion
Add
Specify a detector
number
[01] ranges between 01 and 64
PSWd
Set password
[00] ranges between 00 and 99
SUPr
Set the measured gas
suppression rate
OFF or 1~50%
PyrO
Set if CEC is used or not
ON / OFF
Py-U
Indicate CEC voltage
Set value between 0.50V and 1.80V
(Display 0.50U ~ 1.80U)
U0.00
Program version number
Prgm
Measurem
ent data
UnIt
Measurement unit
%LEL, %VOL, PPM, PPB
dP-S
Specify location of the
decimal point
Set 0000, 0.000, 00.00 or 000.0
H-SL
Set Full Scale
Set value between 0 and 9999
CALb
Calibration
mode
ZERO
ZERO Calibration Mode
YES/NO
Set ZERO Calibration
0.0
Measured value display
mode
WAIt
Under zero calibration
0.0
Measured value after
completing calibration
SPAN
SPAN Calibration Mode
YES/NO
Span calibration setting
50.0
Span calibration value
50.3
Measured value of
standard gas
WAIt
Under span calibration
50.0
Measured value after
completing calibration
ALAm
Alarm
setting
LACH
Alarm occurrence setting
ON/OFF
AL-1
Alarm1 value setting
0 ~ 90% of Full scale setting
1H/1L
Alarm1 operational
direction
H: Upward Alarm
L: Downward Alarm
AL-2
Alarm2 value setting
0 ~ 100% of Full scale setting
2H/2L
Alarm2 operational
direction
H: Upward Alarm
L: Downward Alarm
LOg
Saving log
CtrL
Log saving mode
ON /OFF
AUto
Set log auto saving mode
ON /OFF
mSdC
Check the external
memory capacity
Display Remaining capacity and total
capacity (displayed in GB units)
[Table 7. Menu Table]

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6.3. Configuration Mode
➢While the device displays ”Stby”(Stand by), press and hold “RUN/MODE”key
more than 2 seconds. Then you will enter menu selection mode.
➢Password entering screen shows up. Input password using “ ”Key or
“ ”Key. If you press “RUN/MODE” key after entering password, then you
enter a configuration menu (“ConF”)
Note1) (Password must be entered, “FAIL” is displayed when “RUN/MODE”
key is pressed in the initial password([--]) status.)
➢Select “COnF”(configuration) using “ ” key or “ ” key and then press
“RUN/MODE”key. You will enter environment configuration mode.
➢“Add”message will show up. In this state, you can set an address that is
used to identify the device when communicating data.
➢If you press ”RUN/MODE”key, then you enter an address setting function.
➢Address is a mode in which you can set the device’s address so as to
identify each detector by PC uniquely. Address number(initially [01]) will
increase or decrease by pressing “ ” or “ ” key.
➢When desired address is displayed, press “RUN/MODE” key. Then the
address is set to be the number displayed in the screen. After that, the
device goes to next item.
➢This is a password mode in which to obtain an authority to change the
program of detector. Password increases or decreases by pressing “ ” or
“ ” key.
➢When the desired password is displayed, press the “RUN/MODE” key to
enter the password change check mode.
➢Select No / YES through the “ ”Key 나“ ”Key to decide whether the
password is changed or not, and press “RUN/MODE” key to check the
changed password.
➢If “No” is selected, the existing password will be retained, and if “YES” is
selected, the password will be changed to the desired password.
➢After checking the changed password, press the “RUN/MODE” key to enter
the next item, “SUPr” mode.
➢If the “RUN/MODE” key is pressed when the password value is the same as
before, it enters the “SUPr” mode without checking the password.
➢This is a suppression mode(“SUPr”) in which you can set suppression
percentage of gas concentration that is supposed to be presented as ‘0’.
The percentage number increases or decreases whenever “ ” key or “ ”

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6.4. Program setting mode
key is pressed. (Possible to set OFF or 1~50, 1% ~ 50% of High scale)
➢When desired number is displayed, press “RUN/MODE” key. Then a
suppression percentage is set to be the number displayed. After that, the
device goes to next item.
➢This is a Pyrolyzer(CEC) mode in which you can set whether Pyrolyzer is
applied or not. When you press “ ” key or “ ” key, it will switch
between ON and OFF alternatively.
➢When desired option is displayed, press “RUN/MODE” key. Then Pyrolyzer
mode is specified. After that, the device goes to next item.
➢If Pyrolyzer is On, it automatically changes to “F-LE”(Flow Level) 250 in
“FLOW” mode and if Pyrolyzer is Off, it automatically changes to “F-
LE”(Flow Level) 500 in “FLOW” mode.
➢This is a “Py-V”mode in which you can set the voltage level used by
Pyrolyzer.
➢When you press ”RUN/MODE”key, you will enter voltage setting function.
➢Pyrolyzer voltage is a mode in which you can set voltage value used by
pyrolyzer of detector. When you press “ ” key or “ ” key, the voltage
level( 1.30V ) will increase or decrease.
➢Voltage can be set between 0.5V and 1.8V. When desired value is
displayed, press “RUN/MODE”key. Then the voltage is set to the value
displayed. After that, the device goes to next item.
➢This is a mode in which program version is viewed.
➢If you press “RUN/MODE” key, you will enter a menu mode.
➢While the screen displays ”Stby”, press “RUN/MODE” key and hold it more
than 2 seconds. Then you will enter menu selection mode.
➢Password entering screen shows up. Input password using “ ”Key or
“ ”Key. If you press “RUN/MODE” key after entering password, then you
enter a configuration menu (“ConF”)
➢Select “Prgm”(programmable) using “ ” key or “ ” key. If you press
“RUN/MODE” key while “Prgm”is being displayed, then you will enter
program setting mode.

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6.5. Zero Calibration
6.5.1. Auto Zero Calibration
➢This is a mode in which gas concentration measurement unit is set. When
you press “ ” or “ ” key, unit icon will be changed at the right side of
screen. (%LEL, %VOL, PPB, PPM)
➢When desired icon is displayed, press “RUN/MODE” Key. Then
measurement unit is set as you select. After that, the device goes to next
item.
➢This is a “dP-S”(decimal point) mode in which you can set the decimal point
position for gas concentration value.
➢Press “RUN/MODE”key while “dP-S”is being displayed, then you will enter
decimal point position setting function.
➢Decimal point is necessary to change depending on measurement range.
Decimal point position can be adjusted in four ways as shown in a left
figure by pressing “ ” key or “ ” key.
➢When desired decimal point is displayed, press “RUN/MODE” Key. Then
decimal point position is set as desired. After that, the device goes to next
item.
➢This is a function to set maximum gas concentration value which is to be
displayed, denoted as “H-SL”(High scale setting).
➢When you press ”RUN/MODE” key, you can enter high scale setting
function.
➢High scale value has been specified within the range in compliance with
domestic standard and regulations when the product is released.
note 1) High scale range can be changed according to customer’s request.
➢High scale value can be adjusted depending on measurement range. When
you press “ ” key or “ ” key, scale value will increase or decrease.
➢When desired value is displayed, press “RUN/MODE” key. Then high scale
value is set to be the desired value.
Note 1) When changing High scale, the following values are automatically
changed. Span calibration gas concentration value is changed to 50% of
High scale, Alarm1 value is changed to 20% of High scale, Alarm2 is
changed to 40% of High scale
➢Alternative way to conduct zero calibration is to start calibration in
measurement state.
➢Insert clean air or 100% nitrogen through gas in port using calibration tool.
➢When you press and hold “AUTO ZERO”key in measurement mode, AUTO
ZERO calibration will start up.

GPD-100 Instruction Manual
PAGE 20 of 29
Rev 1.2(2021.09.29)
6.5.2. Manual Zero Calibration
➢While zero calibration is being performed automatically, “WAIt”message
will display on LCD. If it completes successfully, “gOOd”(Good) will appear
on LCD.
➢If Zero Calibration fails, “FAIL”will show up during 2 seconds. Then the
device will transit to the calibration mode.
➢While the screen displays ”Stby”, press “RUN/MODE” key and hold it more
than 2 seconds. Then you will enter menu selection mode.
➢Password entering screen shows up. Input password using “ ” or “ ”
key. If you press “RUN/MODE” key after entering password, then you will
go to a configuration menu (“ConF”)
➢Select “CALb”(Calibration) by using “ ” or “ ”Key and press
“RUN/MODE” key to switch to the Zero / Span Calibration standby screen.
➢While “ZERO”icon at the left corner of the bottom is blinking, press
“RUN/MODE” key. Then you will enter Zero Calibration mode.
➢You can set No/YES using “ ” key or “ ” key.
➢If you select YES, you will enter zero(0) calibration mode.
➢The screen to check the measured gas concentration value is displayed.
➢Insert clean air or 100% nitrogen through gas in port using calibration tool.
➢Once the measured value is stabilized, press “RUN/MODE” key. Then zero
calibration will be conducted automatically with indicating “WAIt”(wait)
message in LCD. If calibration is successfully finished, “g00d”(Good) will
show up.
➢If Zero Calibration fails, “FAIL”will appear and remain for 2 seconds. Then it
will return to the display where measured concentration value displays.
➢If you press “RUN/MODE” key or “RESET” key on the current measurement
concentration value screen, the “SPAN” icon blinks and the gas calibration
(Span Calibration) standby screen is displayed.