GASTRON GTD-1000T Series User manual

GTD-1000Tx(M)
Instruction Manual
Headquarters / Engineering research laboratory :
23 Gunpo Advance d Industry 1-ro(Bugok-dong), Gunpo-si, Gyeonggi-do
Tel [phone] Fax [phone]
Yeongnam business office / Plant :
55 Gonghangap-gil 85beon-gil, Gangseogu, Busan Metropolitan City
Tel [phone] Fax [phone]
E-mail : [email protected]
www.gastron.com
Read in detail for correct use.

* KOSHA GUIDE : P-135/6-2018
Calibration must be performed at a frequency requested by the manufacturer and shall be performed quarterly
when the calibration period is not specified.
Gas & Flame
Detection System
GTD-1000Tx(M)
Instruction Manual
www.gastron.com
02_03
Greetings
When abnormalities occur after purchasing the
product, please contact the following address.
· Address : 23 Gunpo Advanced Industry 1-ro,
Gunpo-si, Gyeonggi-do
· Tel : [phone]
· Fax : [phone]
· URL : www.gastron.com
· e-mail : [email protected]
We sincerely thank you for purchasing the product of Gastron Co. Ltd.
Our Gastron Co.Ltd. is a company specialized in Gas detector and Gas Monitoring System, being recognized
by many consumers due to the best quality and use convenience. We always enable you consumers to find
desired products nearby and are ceaselessly studying and striving for development of Gas detectors satisfying
customers. From now on, solve all anguishes concerning Gas detector with the products of Gastron Co. Ltd,
We Gastron Co. will take a responsibility and give you satisfaction.
In the present instruction manual, operation method for Gas detector as well as simple methods for
maintenance and repair, etc. are recorded If you read it in detail and keep it well, for reference when you
have questions, then it will give you much help.
The present product and the product manual can be changed without advance notice for performance improvement
and use convenience of the product.
■ForaccurateoperationofGasdetector,checkupandcalibrateformorethanonceinevery6months.
( * In reference to KOSHA GUIDE: P-135/6-2018 / 7.2 In-house inspection, section 2 )
■ForaccurateoperationofGasdetector,checkupandcalibrationwithcalibrationgasbefore
measurement is recommended.
■Whennotcalibrated,itmaycausemalfunctionoftheequipmentduetoproblemsresultingfrom
Sensor aging.
■Whenthepresentinstrumentshouldbedismantled,thosewithprofessionalskillsforGasdetector
should conduct the operation.
■Forpowersupplycable,wirespecificationsshouldbedeterminedbyreferringtotheitemof"Length
 ofinstalledcable".
■ForthecontentsoncheckupandcalibrationofGasdetector,pleaseuseourcompany'sengineering
department , e-mail, or web site.

www.gastron.com
04_05
ContentsContents
GTD-1000Tx(M)
Instruction Manual
7.2.1. Zero Calibration······································································································································· 21
7.2.2. Span Calibration······································································································································ 22
7.3. ALARM Mode···················································································································································· 23
7.4. Device Mode······················································································································································ 24
8. Troubleshooting·························································································································································· 25
8.1. Fault List ····························································································································································· 25
8.2. Recovery List······················································································································································· 25
9. Interface Configuration············································································································································· 26
9.1. MODBUS RS485 ················································································································································ 26
9.1.1. Interface setting ······································································································································ 26
9.1.2. MODBUS RS485 Register map··············································································································· 26
10. Drawings and Dimensions········································································································································ 27
10.1. Standard Type ···················································································································································· 27
11. Precautions before Installation ································································································································ 28
11.1. Selecting a Place for Installation (Occupation Safety and Health Act Data) ···················································· 28
11.2. Selecting a Site for Installation (High-Pressure Gas Safety Control Act Data) ················································· 28
11.3. Precautions during Installation·························································································································· 28
12. Revision History··························································································································································· 30
1. Overview ······································································································································································ 6
2. Configuration······························································································································································ 6
3. Specification ································································································································································ 7
3.1. Basic Specifications ············································································································································ 7
3.2. Mechanical Specifications ································································································································· 7
3.3. Electrical Specifications (Standard Type)··········································································································· 8
3.4. Environmental Specifications ···························································································································· 8
4. Name and Description of Each Part························································································································ 9
4.1. Components ······················································································································································ 9
5. Installation ····························································································································································· 11
5.1. Detachment of Housing Cover·························································································································· 11
5.2. Main PCB Configuration···································································································································· 12
5.3. Terminal Configuration······································································································································ 13
5.3.1. Wiring for 4~20mA Source Operation Type ·························································································· 14
5.3.2. Wiring for 4~20mA Sink Operation Type······························································································· 14
5.3.3. Wiring for 4~20mA 3Wire Sink Operation Type···················································································· 15
5.4. Installation Cable Length ··································································································································· 15
6. Detector Operation Flow ·········································································································································· 17
6.1. Initial Operation Status (Power On) ·················································································································· 17
6.2. Measuring Mode ··············································································································································· 17
6.3. Operation Flow ·················································································································································· 18
6.4. Menu Configuration Table ································································································································ 19
7. System Mode ······························································································································································ 20
7.1. PROGRAM MODE ············································································································································· 20
7.2. CALIBRATION MODE········································································································································· 21

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06_07
3. Specication
GTD-1000Tx(M) toxic gas detector has been developed to detect gas leaked from industrial sites and various toxic gases
generated from factories, gas storages, and manufacturing processes that produce or use toxic gases and to prevent
accidents in advance.
GTD-1000Tx(M) toxic gas detector is installed in areas with gas leak hazards and continuously monitors gas leak. It
provides DC 4-20 mA standard output signal and RS-485 network signal. Also, DC 4~20 mA standard output enables
transmission distance of the output signal between detector and receiver at maximum 2,500 m (when using cables with
CVVS or CVVSB 1.5 sq or higher). RS-485 network signal can be transmitted up to 1,000 m (when using a designated
cable for RS-485). GTD-1000Tx(M) toxic gas detect must be used at a height below 1,000 m above sea level.
Body of GTD-1000Tx(M) is made of Aluminum alloy and the gas sensor module is made of stainless steel. It consists of
a complete explosion-proof enclosure (Ex d IIC T6). This product can be installed in all areas prone to toxic gas leak and
explosion hazards.
Internal configuration consists of 1 terminal PCB board that outputs measurements externally (DC 4-20 mA, RS-485).
External configuration consists of detector part that monitors gas leak and cable inlets.
It can perform calibration using detachable display (LCD or OLED), therefore maintenance is convenient.
2. Conguration
1. Overview
GTD-1000Tx(M)
Instruction Manual
[Figure 1. GTD-1000Tx(M) Overview]
Gas
Sensor Module
(GSA860EX)
Main Board
(Transmitter)
+24V DC
4-20mA Analog
Signal Output
Transmitter enclosure
Safety Power Supply Unit
(24VDC)
Safety Controller
(PLC or DCS)
GTD-1000TX(M) Gas Detector
Hazardous Area (Filed) Safe Area
제어Signal
External Interface
Power Line
Legend
※Note1.Refertothemeasuredgaslistformeasuredgasesandtheirranges.Contactusforspecialgas.
3.1. Basic Specifications
3.2. Mechanical Specifications
ITEMS SPECIFICATION
Measuring Type Diffusion
Measuring Method
- Electro-Chemical Cell
- Heated-semiconductor Cell
- Photoionization detector(PID)
Detectible Gas Toxic Gas (Note1)
Measuring Range Capable to display 000.0 ~ 10000 (Note 1)
Accuracy ≤±3%/FullRange
Zero Drift ≤2%/FullRange
Response Time Depends on Sensor Module.
Refer to Sensor Specification or Contact in case for Special Gas.
Approvals Classification) KCs: Ex d llC T6,T5,T4, IP65
Basic Interface Analog 4-20mA current interface
Rs-485 Interface RS-485 MODBUS (Option)
Option
RS-485 Board
GTL-100 Warning Light
Rain Cover
Warranty Transmitter 2Year
Sensor 1Year
ITEMS SPECIFICATION
Eexplosion Proof type Explosion-proof enclosure
Dimension 136(W) × 176(H) × 95 (D) mm
Weight including Sensor App. 1.5kg
Mounting type Wall mount
Mounting Holes Ø7±0.1
Cable inlet 3/4"PF(1/2"or3/4"NPT)
Body material Transmitter aluminum alloy
Sensor Stainless Steel (STS316)

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08_09
4. Name and Description of Each Part
3.3. Electrical Specifications (Standard Type)
ITEMS SPECIFICATION
Input Voltage(Standard)
※CustomersuppliedPSUmustmeet
requirements IEC1010-1 and CE
Marking requirements.
Absolute min:
Nominal:
Absolute max:
Ripple maximum allowed:
18V
24V
31V
1V pk-pk
Wattage Max. wattage:
Max. current:
3.6W @+24 VDC
150mA @+24 VDC
Analog output Current
0-20mA(500 ohms max load)
Allreadings±0.2mA
Measured-value signal:
4mA(Zero) to 20mA(Full Scale)
Fault:
0-100%LEL:
100-109%LEL:
Over110%LEL:
Maintenance:
0mA
4mA - 20mA
20mA - 21.4mA
22mA
3mA
Analog output current ripple & noise max ±20uA
Wiring requirement Power CVVS or CVVSB with shield
Analog CVVS or CVVSB with shield
Cable Connection Length Analog 2500m
RS-485 1000m
EMC Protection: Complies with EN50270
3.4. Environmental Specifications
ITEMS SPECIFICATION
Operation Temperature Transmitter -20to50℃
Sensor Refer to Sensor Specification
Storage Temperature Transmitter -20to50℃
Sensor Refer to Sensor Specification
Operation Humidity Transmitter 5to99%RH(Non-condensing)
Sensor Refer to Sensor Specification
Pressure Range 90 to 110KPa
Max. air velocity 6m/s
3. Specication
GTD-1000Tx(M)
Instruction Manual
4.1. Components
[Figure 2. GTD-1000Tx(M) Components]
NO NAME DESCRIPTIONS
1Housing Body Protects PCB Board built in Sensor and Housing from external environmental change and shock.
2Housing Cover It is assembled with detector housing body and protects PCB Board built in Sensor and Housing from
external environmental change and shock
3Sensor It is a site that detects actual gas leak. It converts the amount of gas leak into electrical signal and
transmits to the Main PCB.
4Internal Ground It must be grounded to inside of detector for protection from external noise or strong electric field.
- Use a conductor that is 4 mm or longer when coupling ground line.
5External Earth Ground It must be grounded to outside of detector for protection from external noise or strong electric field.
- Use a conductor that is 4 mm or longer when coupling ground line.
6Conduit Connection It is supplied for inlet of power supply and measurement output signal for the detector during
installation.Forcableinlet,PForNPT1/2",3/4"areprepared.
7Main PCB Amplifies fine outputs generated from Sensor Element to transmit a converted output in 4~20 mA
DC standard. It sends data to display part.
8Mount Hole Hole to fix the gas detector on external wall or other installation sites.

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No ITEMS SPECIFICATION
9Power/Signal Terminal
CN6 consists of DC 24 V power supply and DC 4~20 mA standard output connection terminal
(VISO, +24V, mA, GND, ETH).
CN7 is RS-485 Modbus network terminal.
10 Sensor Terminal CN5 is Sensor Connection Terminal.
11 Display Terminal CN5 is a terminal that connects to display board. Display board is attached for test and calibration.
12 Model Name Plate It displays product’s model name, measuring gas, and serial number, etc.
13 Set Screw(M4-L6) It is a set screw that prevents cover opening from the detector housing body.
[Table 1. GTD-1000Tx(M) Components Description]
4. Name and Description of Each Part
GTD-1000Tx(M)
Instruction Manual
[Figure 3. Slotted Set Screw]
5. Installation
■Itisprohibitedforanindividual,otherthananapproveduseroratechnicianresponsibleforinstallationandrepair
from the head office, to install a gas leak sensor on site or open the cover of the installed gas leak sensor and
manipulate it. This may cause serious loss of life and property from fire, explosion, and etc. In addition, please check
whether there is any remaining explosive gas or combustible material in the surroundings. Power must be turned off
before performing work.
5.1. Detachment of Housing Cover
■<Warning-Donotopenwhenelecticalcurrentisflowing>
■Turntheslottedsetscrew(M4x1ea)fixingthecoverpartofmainbody3~4tunscounterclockwise(ccw)using
a hex wrench (M2) then turn the cover of gas leak detector ccw to detach the cover. When the cover is detached, LCD
appears.

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5. Installation5. Installation
GTD-1000Tx(M)
Instruction Manual
[Figure 4. Main PCB Terminal Layout]
5.2. Main PCB Configuration
■Afterdetachingthedisplayparts,theMainPCBterminallayoutappearsasshowninthefigurebelow.
■UsingOC1,OC2,andOC3showninthelayoutabove,RS-485optionboardcanbeattachedand3ØScrew 
holes located at top left of RS-485 option board are used for fixing.
[Table 2. Main PCB Key Part Description]
No NAME DESCRIPTION
1CN6 Power & Output Signal Terminal
3CN7 RS-485 Terminal
3J1 4~20mA Source / Sink Selection Jumper ( ON: Source Type, OFF: Sink Type)
4CN4 Display LCD Connector
5CN5 Sensor Connector
6CN2 Program download Connector
7D1 Status LED (Flashes in 1 sec interval during normal operation)
8OC1,OC2,OC3 RS-485 Option Board Connector
9CN3 Warning light (GTL-100) Interface Connector
5.3. Terminal Configuration
■<Warning-Turnoffpowerbeforeconnectingpowerterminal>
■Loosen5terminalfixingscrewslocatedattoppartofdetachedterminalblockCN6(VIS,+,mA,-,ETH)Connectorby
 turningcounter-clockwiseusingaΘdriver.ConnectDC18~24Vpowerto+,and-thenconnectsignalcabletomA.
Tighten 5 terminal fixing screws clockwise (cw) so that terminal does not leave the track then insert Main PCB as the
same condition before disassembly.
[Table 3. CN6 Terminal Detailed Description]
NO PCB SILK PIN NAME DESCRIPTION
4~20mA Source Drive (J1 Jumper ON) 4~20mA Sink Drive (J1 Jumper OFF)
1VISO VIS N.C 4~20mA Sink In(+)
2+24V ++24V / POWER (+)
3mA mA 4~20mA Source Out 4~20mA Sink Out(-)
4GND -GND / POWER (-)
5ETH ET EARTH
■UseCVVSorCVVSB2.0sq↑ShieldCableforterminalconfiguration.
[Table 4. CN7 Terminal Detailed Description]
NO PCB SILK DESCRIPTION
1RS485A RS485A Terminal
2RS485B RS485B Terminal
[Figure 5. CN6, CN7 Terminal Configuration]
Terminal Set Screw

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5. Installation5. Installation
GTD-1000Tx(M)
Instruction Manual
5.3.1. Wiring for 4~20mA Source Operation Type 5.3.3. Wiring for 4~20mA 3Wire Sink Operation Type
5.3.2. Wiring for 4~20mA Sink Operation Type 5.4. Installation Cable Length
■Connect4-20mAsignalterminalatPLCsideto'mA'
of GTD-1000Tx(M). GND terminal is used in common
with power. Then, turn on the J1 jumper.
■Connect(+)and(-)terminalsfor4-20mAsinkoutput
at PLC side to VISO terminal and power (24V DC)
 (-)terminal,respectively.Connect'mA'terminalof
 GTD-1000Tx(M)to'GND'terminal.Then,turnoffthe
J1 jumper.
■Connect(+)and(-)terminalsfor4-20mAsink
 outputatPLCsidetoVISOterminaland'mA'terminal,
respectively.
Then, turn off the J1 jumper.
■ThemaximumlengthbetweenGTD-1000Tx(M)andpowersupplyisdecidedbywirespecification.
■Max.InstallationLength=VMAXDROP÷IMAX÷WIRER/m÷2
 ·VMAXDROP:MaximumPowerLoopVoltageDrop(=PowerSupplyvoltage
- min operating voltage)
 ·IMAX:Max.CurrentofGTD-1000Tx(M)
 ·WIRER/m:Theresistanceofthewire(ohms/metervalueavailableinwiremanufacturer'sspecificationdatasheet)
■Exampleofinstallationlengthsusing24Vpowersupplyand16AWGisasfollows.
 ·GTD-1000Tx(M)minimumoperatingvoltage=18Vdc
 ·VMAXDROP=24-18=6V
 ·IMAX=0.15A(150mA)
 ·6÷0.15÷0.01318÷2=1,517.451m≒1,517m
[Figure 6. 4-20mA Source Configuration] [Figure 8. 4-20mA 3Wire Sink Configuration]
[Figure 7. 4-20mA Sink Configuration]

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16_17
5. Installation
GTD-1000Tx(M)
Instruction Manual
■Powercableinstallationforeachcabletypeisasshowninthetablebelow.
AWG mm2 COPPER RESISTANCE(ohms/m) METERS
12 3.31 0.00521 3838
14 2.08 0.00828 2415
16 1.31 0.01318 1517
18 0.82 0.02095 954
20 0.518 0.0333 600
[Figure 9. Calculation of GTD-1000Tx(M) Installation Cable Length]
[Table 5. GTD- 1000Tx(M) Power Cable Installation Length]
6. Detector Operation Flow
Display board is connected and used during maintenance and repair. For normal display operation after connecting in
operation status, contact ‘RESET’ key.
6.1. Initial Operation Status (Power On)
■ AfterwiringtopowerterminalatthetopofMainPCBboardthensupplypower,thefollowingcontentsare 
displayed on LCD. Approx. 30 min of stabilization of time is needed from the initial supply of operation power and
it starts to operate normally after sufficient stabilization.
GTD-1000
[V X.XX] - When power turns on, model name and product firm ware version are displayed on LCD.
SELF TEST
[ >>>0179]
-Selftestisperformedfor3min(30minforO2set-up),'>'symbolinthesecondrowshows
- the progress.
[ %LEL]
[ 0.0]
- In normal operation mode, it runs as below.
- In the first row, measured gas name and unit are displayed in 1 sec interval. In the second row,
- the current measurement is displayed.
-Inthecurrentscreen,touchingthemagnet-baron'Func'keyfor2secorlongerchangestosettingmode.
※DuringModbusnetwork,'*'isdisplayedontheleftofthefirstrow.
※ENG.Whenthemodeison,'<'isdisplayedontheleftofthesecondrow.
[ COMB.]
[ 0.0]
[ %LEL]
[ 30]
- When alarm1 or 2 occurs, it runs as below. (It runs only when alarm used setting in alarm mode is on.)
- The first row runs the same as in normal status. In the second row, alarm message and gas
- measurement are displayed in 1 sec interval.
- When GTL100 explosion-proof warning light is installed, upon an event of alarm1, red LED and buzzer
- flicker and run in 1 sec interval. Upon an event of alarm2, they continuously run without flickering.
- If alarm latch is on, the alarm continuously run until it is released using the reset key.
[ %LEL]
[ ALARM1 ]
[ %LEL]
[ OVER ]
-Whengasmeasurementlargerthan10%ofsethighscalevalue,"OVER"displaysin1secinterval.
- At this time, 4~20 mA runs as 22 mA.
[ %LEL]
[ UNDER ]
-Whengasmeasurementsmallerthan-10%,"UNDER"displaysin1secintervaland4~20mAruns
- below 2 mA.
- ※ThefollowingfunctiononlyrunswhenUNDERison.
[FAULT8]
SEN HUNT
- When trouble occurs in the device, it displays fault number and message.
- At this time, 4~20 mA runs below 2 mA.
- Fault #8 on the left is a mode that is displayed when there is repeated hunting error from the sensor.
6.2. Measuring Mode
■Afterpoweron,whenthereisnoerrorfrom"SELFTEST",itautomaticallyentersMeasuringMode.

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18_19
GTD-1000Tx(M)
Instruction Manual 6. Detector Operation Flow6. Detector Operation Flow
6.3. Operation Flow 6.4. Menu Configuration Table
■Operationkeysfordetectorsystemmodearedefinedasbelow.
[Figure 10. GTD-1000Tx(M) Mode Configuration]
ITEM NAME DESCRIPTION
FUNC Function key Detector Mode Setting Entry Function (Insert Magnetic-bar for 2 sec or longer in measuring mode)
Level2 Next stage entering function and setting saving function
RESET Reset key Move to the previous stage from the level entered.
↑Up key Next level mode that is configured in LEVEL1 and Change in Level2 setting Plus
↓Down key Next level mode that is configured in LEVEL1 and Change in Level2 setting Minus
LEVEL1 LEVEL2 DEFAULT
NAME PARAMETER
PROGRAM
MODE
GAS TYPE (Gas Type) [DEFIN./USER] DEFIN.
GAS SEL(Gas Select) Built-in gas name selection COMB.
UNIT SEL (Unit Select) %/%LEL/PPM/PPB %LEL
D-POINT(Decimal Point) 0.100/1.00/10.0/100 100
HIGH SCL (High Scale) 1~10000 100
PASSWORD 00~99 00
CALIBRA.
MODE
(Calibration Mode)
CALIBRA.
[ZERO]
(Calibration Zero)
ZERO CAL
[NO,YES] [NO]
ZERO GAS
[ 0]
ZERO>>>>
[SUCCESS / FAIL]
CAL. DATA
[ 0/ FAIL]
CALIBRA.
[SPAN]
(Calibration Span)
SPAN CAL
[NO , YES] [NO]
SPAN GAS
[ 0]
SPAN SET
[ 50/ FAIL] 50
SPAN>>>>
[SUCCESS / FAIL ]
CAL. DATA
[ 0]
ALARM
MODE
ALM USED (Alarm Used) [OFF / ON] OFF
AL LATCH (Alarm Latch) [OFF / ON] OFF
A1 LEVEL (Alarm-1 Level) [1 ~ 10000] 20
A1 TYPE (Alarm-1 Type) [INC / DEC] INC
A1 DBAND (Alarm-1 Dead Band) [0.0~10.0%F.S] 0
A1 TIME (Alarm-1 Time) [0~ 60]SEC 1
A2 LEVEL (Alarm-2 Level) [1 ~ 10000] 40
A2 TYPE (Alarm-2 Type) [INC / DEC] INC
A2 DBAND (Alarm-2 Dead Band) [0.0~10.0%F.S] 0
A2 TIME (Alarm-2 Time) [0~ 60]SEC 1
DEVICE MODE 485 B/D [CHECK / EMPTY]
ADDRESS [0 ~ 64] [1]
SENSOR MODE Factory Setting
MAINTEN.MODE Factory Setting
VERSION MODE Factory Setting
TEST MODE Factory Setting
■Afterpoweron,itpassesself-diagnosticprocessthenentersMeasuringMode.Here,byoperatingfrontkeys,
you can go to internal System Mode.
■TimeoutforLevel1andLevel2are10sec.Itissetto1hforLevel2CalibrationandTestMode.
■When"RESET:keycontactsatProgramModeScreen,itreturnstoMeasuringMode.When"RESET"keycontacts
at each Program Setting Screen, it returns to the parent step.

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20_21
GTD-1000Tx(M)
Instruction Manual
7.1. PROGRAM MODE
PASSWORD
[**]
-Contacting"FUNC"keyfor2secorlongerinMeasuringModeentersPasswordmode.
-AftersettingPasswordusing"↑"or"↓"key,contact“FUNC"key.
PROGRAM
MODE
- If password is correct, it enters Program mode.
-Bycontacting"↑"or"↓"key,modechangesindefinedorder.
- (PROGRAM->CALIABRA.->ALARM->SENSOR->MAINTEN.->DEVICE->VERSION->TEST)
GAS TYPE
[ DEFIN. ]
-Modethatsetsgasnametypeandcontacting"↑"or"↓"keychangesgastype.
- (DEFIN. / USER)
- DEFIN. Is acronym for Define and is selected when using built-in setting of gas name.
- USER is selected when the user directly sets a gas name.
-Whenadesiredgastypeisdisplayed,contact"FUNC"keytosetthegasnameandenterProgramMode.
GAS SEL
[ COMB. ]
-Modethatsetsgasnameandcontacting"↑"or"↓"keychangesgasname.
- When gas type is set to DEFIN., built-in gas names can be selected for use. When it is set to USER,
- the user shall set gas name using 5 character for use. Characters allowed for use are number, capital
- Alphabet, space, and period. When position is moved by setting characters, a cursor in black box shape
- appears as shown in the figure on left.
USER GAS
[■ ]
UNIT SEL
[ %LEL ]
-Modethatsetsgasmeasuringunitandcontacting"↑"or"↓"keychangesgasmeasuringunit.
- (%/%LEL/PPM/PPB).
-Whenadesiredgasmeasuringunitisdisplayed,contact"FUNC"keytosettheunitandenterProgram
- Mode.
D-POINT
[ 100]
-Modethatchangesdecimalplaceandcontacting"↑"or"↓"keychangesdecimalplace.
- (0.100/1.00/10.0/100)
-Whenadesireddecimalplaceisdisplayed,contact"FUNC"keytosetthedecimalplaceandenterthe
- next Program Mode.
HIGH SCL
[ 100]
-Modethatsetshighscalevaluethatshouldbedisplayedforfullrange.Contacting"↑"or"↓"key
- increases or decreases the scale value.
- ( 1 ~ 10000 )
-Whenadesiredhighscaleisdisplayed,contact"FUNC"keytosetthehighscalevalueandenterthe
next Program Mode.
PASSWORD
[00]
- It is password setting mode. This password is checked when entering Program Mode.
-Setusing"↑"or"↓"keythencontact"FUNC"keytosetthepasswordandenterthenextProgramMode.
7. System Mode7. System Mode
7.2. Calibration Mode
7.2.1. Zero Calibration
PASSWORD
[**]
-Contacting"FUNC"keyfor2secorlongerinMeasuringModeentersPasswordmode.
-AftersettingPasswordusing"↑"or"↓"key,contact"FUNC"key.
CALIBRA.
MODE
-Contact"↑"or"↓"keytoselect"CalibrationMode".
-Contact"FUNC"keywhen"CALIBRA.MODE"isdisplayedtoenterCalibrationMode.
-Contact"RESET"keytoreturntoMeasuringMode.
CALIBRA.
[ZERO]
-When“CALIBRATIONMODE”isdisplayed,contacting"FUNC"keyselectsZeroCalibration.
-Contact"↑"or"↓"keytoachieve[ZERO]thencontact"FUNC"keytoenterZeroCalibration.
ZERO CAL
[ NO] -Contact"↑"or"↓"keytoachieve[YES]thencontact"FUNC"keytoperformZeroCalibration.
ZERO GAS
[ 0]
-Usingacalibrationtool,injectcleanairor100%nitrogenintothesensorataflowrateof500mL/min
- for1min.Contact"FUNC"keywhenmeasurementisstabilizedtoautomaticallyperformZeroCalibration.
ZERO >>
[SUCESS]
-Whenzerocalibrationissuccessful,“ZEROSUCCESS"isdisplayedfor2seconLCDdisplaythenit
- changesto"CALIBRATIONDATA"Mode.
-Whenzerocalibrationisnotsuccessful,"ZEROFAIL"isdisplayedfor2secanditchangesto
- "CALIBRATIONDATA"Mode.
-ZEROFAILoccurswhensensorinputvalueexceeds70%oftotalADCinputrange.
ZERO >>
[ FAIL ]
CAL.DATA
[ 0]
- It is a mode to display measurement after calibration and checks whether calibration is successful after
- performing auto calibration.
-Whenitfailed,itdisplays"FAIL"andthecurrentmeasurementin1secinterval.
-Contact"RESET"keytoreturnto"Calibrationmode".
■Duetocharacteristicsofthegasdetector,minimum30minofstabilizationtimeisrequiredandmaintenance
condition may change depending on site condition..

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22_23
GTD-1000Tx(M)
Instruction Manual 7. System Mode
7.2.2. Span Calibration
CALIBRA.
MODE
-Contact"↑"or"↓"keytoselect"CalibrationMode".
-Contact"FUNC"keywhen"CALIBRA.MODE"isdisplayedtoenterCalibrationMode.
CALIBRA.
[SPAN] -Contact"↑"or"↓"keytoachieve[SPAN]thencontact"FUNC"keytoenterSpanCalibrationmode.
SPAN CAL
[ NO] -Contact"↑"or"↓"keytoachieve[YES]thencontact"FUNC"keytoperformSpanCalibration.
SPAN GAS
[ 50]
- Using a calibration tool, inject the standard gas to the sensor at a flow rate of 500 mL/min for 90 sec.
- Afterthemeasurementisstabilized,contact"FUNC"keytoenterthenextmode.
- When Hold function in Maintenance Mode is on, the current maximum SPAN gas value is held and
- displayed in the first row.
- The current measurement is displayed in the second row.
[ 50]
[ 50]
SPAN SET
[ 50]
-Itisamodetosetstandardgasvalue.Whenthereisno"Fail"message,contact"↑"or"↓"keyto
- set a value.
- When the inject standard gas value is abnormal, it displays Fail message. Fail message is as follows.
- Fail message and span set value are displayed alternatively.
- ①"LOWFAIL"occurswhenthedifferencebetweeninjectedgasvalueandzerocalibrationvalueis
below1%.
- ②"HIGHFAIL"occurswheninjectedgasvalueisabove95%oftotalADCinputrange.
-"RINGFAIL"occurswheninjectedgasvaluerunsinthecurrentsetspanvalue,itexceeds95%ofADC
- input range. The above FAIL messages are automatically released if the status is normal after adjusting
- SPAN value.
SPAN SET
LOW FAIL
SPAN SET
HIGH FAIL
SPAN >>
[SUCESS]
-Aftercompletingstandardgasvaluesetting,contacting"FUNC"keyautomaticallyrunsSpan
- Calibration.Whenitsuceeds,"SPANSUCCESS"isdisplayedonLCDdisplayfor2secthenitchanges
- to"CALDATA"Mode.
-Whenspancalibrationisnotsuccessful,"SPANFAIL"isdisplayedfor2secanditchangesto
- "Cal.DataMode".
SPAN >>
[ FAIL ]
CAL.DATA
[ 0]
- It is a mode to display measurement after calibration and checks whether calibration is successful after
- performing auto calibration.
-Contact"RESET"keytoreturnto"Calibrationmode".
7. System Mode
7.3. ALARM MODE
PASSWORD
[**]
-Contacting“FUNC”keyfor2secorlongerinMeasuringModeentersPasswordmode.
-AftersettingPasswordusing"↑"or"↓"key,contact"FUNC"key.
ALARM
MODE
-Contact"↑"or"↓"keytoselect"AlarmMode".
-Contact"FUNC"keywhen"ALARMMODE"isdisplayedtoenterAlarmsettingmode.
-Contact"RESET"keytoreturntoMeasuringMode.
ALM USED
[ ON]
- It is a setting where Alarm Mode Setting is turned on or off.
-Contact"↑"or"↓"keytochangeON/OFFstatus.WhenitisON,AlarmfunctionandAlarmMode
- setting can be performed.
- GTL-100 explosion-proof warning light can only be used when it is ON.
-Contacting"FUNC"keyentersthenextmode.
AL LATCH
[ ON]
-ItisamodethatsetsResetmethodafterrunningofAlarm1.Contact"↑"or"↓"keytochange"ON"and
- "OFF".
-"OFF"setstoautomaticallyresetthealarm."ON"settoresetthealarmonlywhenResetkeyispressed.
-Contact"FUNC"keywhenadesiredmodeisdisplayedtosetthenenterthenextalarmsettingmode.
A1 LEVEL
[ 20]
-ItisamodethatsetsAlarm1level.Contact"↑"or"↓"keytoincreaseordecreaseAlarm1level,
- respectively.
-Whenadesiredalarm1thresholdisdisplayed,contact"FUNC"keytosetitandenterthenextitem.
A1 TYPE
[INC] -ItisamodethatsetsoperationaldirectionofAlarm1.Contact"↑"or"↓"keytodisplay"INC"or"DEC".
-"INC"modeoperateswhenthevalueisequalorlargerthansetalarmthreshold."DEC"modeoperates
- when the value is equal or less than set alarm threshold.
-Contact"FUNC"keywhenadesiredmodeisdisplayedtosetthenenterthenextmode.
A1 TYPE
[DEC]
A1 DBAND
[ 0]%F
-ItisamodethatsetsDeadbandvalueforAlarm1operation.Use"↑"or"↓"keytosetavalue.
- It is a function where Alarm1 operates at values above the sum of Alarm1 level and dead band values
- and releases at values below Dead band value subtracted from Alarm1 level.
-Whenadesiredalarm1deadbandisdisplayed,press"FUNC"KEYtosetitandenterthenextitem.
A1 TIME
0 SEC
- It is a function to prevent instantaneous malfunction of detector due to external shock and noise other
- than from normal operation and time can be set in a range between 0~60 sec.
-ForAlarm1dwelltimesetting,press"↑"or"↓"keytoincreaseordecreaseinunitof1sec,respectively.
-WhenadesiredAlarm1dwelltimeisdisplayed,press"FUNC"KEYtosetitandenterthenextitem.
-Ex.)Alarmthresholdvalue:20%LEL/Delaytime:Whenitisat5sec,Alarmtriggerswhenthe
- measuredvalueisabovethesetvaluebasedon20%LELfor5secorlonger.Whenitgoesdownbelow
- the set value within 5 sec, alarm is not triggered.
A2 LEVEL
[ 20]
-ItisamodethatsetsAlarm2level.Contact"↑"or"↓"keytoincreaseordecreaseAlarm2level,respectively.
-Whenadesiredalarm2thresholdisdisplayed,press"FUNC"KEYtosetitandenterthenextitem.

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24_25
GTD-1000Tx(M)
Instruction Manual 7. System Mode
A2 TYPE
[INC]
-ItisamodethatsetsoperationaldirectionofAlarm2.Contact"↑"or"↓"keytodisplay"INC"or
- "DEC".
-"INC"modeoperateswhenthevalueisequalorlargerthansetalarmthreshold."DEC"mode
- operates when the value is equal or less than set alarm threshold.
-Contact"FUNC"keywhenadesiredmodeisdisplayedtosetthenenterthenextmode.
A2 TYPE
[DEC]
A2 DBAND
[ 0]%F
-ItisamodethatsetsDeadbandvalueforAlarm2operation.Use"↑"or"↓"keytosetavalue.
- It is a function where Alarm2 operates at values above the sum of Alarm2 level and dead band
- values and releases at values below Dead band value subtracted from Alarm2 level.
-Whenadesiredalarm2deadbandisdisplayed,press"FUNC"KEYtosetitandenterthenextitem.
A2 TIME
0 SEC
- It is a function to prevent instantaneous malfunction of detector due to external shock and
- noise other than from normal operation and time can be set in a range between 0~60 sec.
-ForAlarm2dwelltimesetting,press"↑"or"↓"keytoincreaseordecreaseinunitof1sec,respectively.
-WhenadesiredAlarm2dwelltimeisdisplayed,press"FUNC"KEYtosetitandenterthenextitem.
-Ex.)Alarmthresholdvalue:40%LEL/Delaytime:Whenitisat5sec,Alarmtriggerswhenthe
- measuredvalueisabovethesetvaluebasedon40%LELfor5secorlonger.Whenitgoesdownbelow
- the set value within 5 sec, alarm is not triggered.
7.4. Device Mode
PASSWORD
[**]
-Contacting"FUNC"keyfor2secorlongerinMeasuringModeentersPasswordmode.
-AftersettingPasswordusing"↑"or"↓"key,contact"FUNC"key.
DEVICE
MODE
-Contact"↑"or"↓"keytoselect“CALIBRA.MODE".When"DEVICEMODE"isdisplayed,
- contact"FUNC"keytoenterDeviceMode.
-Contact"RESET"keytoreturntoMeasuringMode.
485 B/D
CHECK
- It is a setting where connection status of RS-485 Board is confirmed.
- When it is connected, it displays CHECK. If not, it displays EMPTY.
ADDRESS
[ OFF ] - It is a setting where RS-485 Modbus Address is set.
-Contact"↑"or"↓"keytochangetheaddress.
ADDRESS
[ 1 ]
8.Troubleshooting
8.1. Fault List
[Table 6. Fault List]
FAULT MESSAGE DESCRIPTION & CONDITION CAUSE
FAULT2
"SENHIGH" Sensor output is above ADC max. value. Defective sensor module or transmitter board ADC
FAULT3
"SENLOW" Sensor output is below ADC min. value. Defective sensor module or transmitter board ADC
FAULT4
"EROMERR" Defective Transmitter EEPROM Checksum Defective Transmitter board EEPROM
FAULT5
"+24VLOW"
It occurs when 24 V main input power is inputed
with voltage below 17V.
Input power below 17 V or defective Transmitter
ADC
FAULT6
"ADCFAIL" Defective Transmitter ADC Defective Transmitter ADC
FAULT7
"H/WREV" H/W Version Error Defective MPU inside Transmitter
FAULT8
"SENHUNT
When there is repeated hunting error in gas
measurement
Sensor output status may be poor or check for input
power noise.
8.2. Recovery List
[Table 7. Recovery List]
No CAUSE SOLUTION
1Defective Sensor Module Change Sensor
2Defective Transmitter Board ADC Change Transmitter Board
3Defective Transmitter Board EEPROM 1) Perform Factory Initialization then correct parameter and re-calibrate
2) Change sensor unit when the same problem occurs again
4Defective MPU inside Transmitter Change Transmitter Main Board
5Poor Sensor Output Status Change Sensor
6Check Input Power Noise Check External Input Voltage Noise Status

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26_27
GTD-1000Tx(M)
Instruction Manual 10. Drawings and Dimensions9. Interface Conguration
9.1. MODBUS RS485 10.1. Standard Type
[Figure 11. GTD-1000Tx(M) Standard Type Drawing]
TYPE ADDRESS BITS DESCRIPTION
Measured Gas
Concentration 30001 BIT15~0 Gas Measurement (Integer/Decimal point is not considered)
High Scale Setting 30002 BIT15~0 High Scale Setting (Integer/Decimal point is not considered)
Alarm 1 Setting 30003 BIT15~0 Alarm 1 Setting (Integer/Decimal point is not considered)
Alarm 2 Setting 30004 BIT15~0 Alarm 2 Setting (Integer/Decimal point is not considered)
Gas detector
status value 10000
BIT0 Alarm 1 Active Status
BIT1 Alarm 2 Active Status
BIT2 Fault Active Status
BIT3 Maintenance Mode Status
BIT4 Test Mode Status
BIT5 Calibration Mode Status
BIT6 Reserved
BIT7 Toggle Bit (Bit reversal in 2 sec interval)
External Test 3BIT0~7 Gas Detector Test Mode Setting
External Reset 2BIT0~7 Exit Gas Detector Test Mode
9.1.1. Interface setting
9.1.2. MODBUS RS485 Register map
■DataFormat:RTU
■Baudrate:9600bps
■Databits:8bits
■Stopbit:1bits
■Parity:Even
■Fordetails,pleasegotowww.modbus.org
[Table 8. RS485 Address Configuration]

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28_29
GTD-1000Tx(M)
Instruction Manual 11. Precautions before Installation
11.1. Selecting a Place for Installation (Occupational Health & Safety Act Data)
A gas leak detector alarm shall be installed in the following places.
■ Around chemical equipment and accessories that have concerns of gas leak. This includes compressors, valves, reactors,
pipe joints, etc. installed inside and outside of a building that handle combustible and toxic materials.
■Placesthatareeasierforgasestostaysuchasareasaroundmanufacturingfacilitieswithignitionsourceslikeheating
furnace, etc,
■Areasaroundequipmentforfillingcombustibleandtoxicmaterials.
■Substations,panelrooms,controlrooms,andetc.locatedwithinexplosivearea.
■Otherareasthatareeasierforgasestostay.
11.2. Selecting a Site for Installation (High-Pressure Gas Safety Control Act Data)
Gas detector of gas leak detector alarm must be installed as close to the areas with concerns of gas leakage as possible.
However, for areas where direct gas leakage is not expected but are easier for leaked gas to stay, the detector must be
installed at the point 1 of the following.
■ Gas leak detector alarm installed outside a building shall be installed at points where gas is likely to stay in consideration
to wind direction, wind speed, specific gravity of gas, etc.
■Gasleakdetectoralarminstalledinsideabuildingshallbeinstallednearthefloorwhenthespecificgravityofgasis
heavier than air and near ventilation of ceiling when it is lighter than air.
■Alarmforgasleakdetectoralarmmustbeinstalledatsiteswherethegasdetectorisinstalledandworkersarepresent.
11.3. Precautions during Installation
Avoid areas with electrical barriers such as rain water, etc. It is recommended to be installed in areas that are easier to
work in since regular maintenance is needed. Avoid areas with vibration or shock since they can affect output values.
Sensor part must be installed towards the direction of gravity.
■Thisequipmenthasexplosion-proofconstructionforinternalpressureandbelongstoGROUPIIforgasandvaporin
general work sites and chemical plants. It can be used in ZONE 1 (ONE) and ZONE 2 (TWO) hazardous sites.
■Allowabletemperatureis85Corbelow,whichcorrespondstoT6.
■Surroundingtemperatureshallbeinarangeof-20to50°C(forMainbody.Forsensor,refertoeachsensormanual.)
■InstallationHeight:1,000Mbelowsealevel
■RelativeHumidity:5%~99%(Non-condensing)
■InstallationSite:IndoorandOutdoor
■ExplosionIgnitionGroupforTargetGasorVapor:ExdIICT6
■ During wiring work, use explosion-proof cable gland at cable inlet or tightly seal cable conduit during metal cable wiring
construction to prevent spread of flames in case of explosion or movement of gas, etc. through the cable conduit within
50 mm. All materials including materials used for sealing of unused inlets must have safety certificates!
■Whenconnectingtheequipmentwithcable,screwthreadmustbetightened5threadsormore.
■ Work in conditions satisfying other [Standards for Selection, Installation, and Maintenance, etc. of Explosion-proof Electric
Machine and Equipment Wiring, etc. at Work Site]
11. Precautions before Installation
[Figure 12. High-Pressure Packing Type] [Figure 13. Y Sealing Compound]
Cable Cable
Inside Inside
Outside Outside
Lead-in unit connector
Lead-in unit connector
Charging compound
Cable-fixing device
Pipe for piping
Cable-fixing device
Sealing ring
Sealing
ring
Connector
Pipe for piping
Compressed
element
Connector for fixing
compressed element

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30_31
GTD-1000Tx(M)
Instruction Manual 12. Revision History
VERSION CONTENTS DATE
1.0 * Manual Initial Revision 2017.11.17
1.1 Changed Address 2018.01.04