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GTD-3000ExW
Instruction Manual
6. Detector Operation Flow
5. Installation
5.5. Installation Cable Length
[Figure12. Calculation of GTD-3000ExW Installation Cable Length]
■ The maximum length between GTD-3000ExW 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-3000ExW
·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-3000ExW minimum operating voltage = 18 Vdc
·VMAXDROP = 24 - 18 = 6V
·IAMX = 0.28A(280mA)
·6 / 0.28 / 0.01318 / 2 = 812.920m = 813m
[Table 7. GTD- 3000ExW Power Cable Installation Length]
AWG
mm
2
COPPER RESISTANCE(ohms/m)
METERS
12
3.31
0.00521
2056
14
2.08
0.00828
1294
16
1.31
0.01318
813
18
0.82
0.02095
511
20
0.518
0.0333
322
■ Power cable installation for each cable type is as shown in the table below.
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-3000
[Ver X.XX]
- When the power turns on, model name is displayed on the first row and firmware version
-
of the detector is displayed on the second row of LCD (OLED).
** SELFTEST **
[>>>>>>> 0179]
- Self test is performed for 3 min '>' symbol in the second row shows the progress.
[ COMB.]
[ 0]%LEL
- It runs as below when it is normal and in gas measuring mode.
- Gas name is displayed on the first row and the current measurement and unit is displayed on the
-
second row.
※ During HART 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.
※ During 485 network, '*' is displayed on the right of the first row
* [ COMB.]
< 0]%LEL
[ COMB.]*A01
[ 0]%LEL
[ COMB.]
[ OVER]%LEL
- 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.
[ COMB.]
[ UNDER]%LEL
- When gas measurement smaller than -10%, "UNDER" displays in 1 sec interval and 4~20 mA
-
runs at 0 mA.
※ The following function only runs when UNDER is on.
[FAULT- 01]
SENSOR EMPTY
- When trouble occurs in the device, it displays fault number and message.
- At this time, 4~20 mA runs at 0 mA. (2 mA when HART is used.)
- It is a mode that displays when Fault #-1 sensor on the left is not equipped.
6.2. Measuring Mode
■ After power on, when there is no error from "SELF TEST", it automatically enters Measuring Mode.
0.28A
