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5. Installation
5. Installation
GTD-2000ExW
Instruction Manual
5.2.3. Wiring for 4~20mA 3Wire Sink Operation Type
■ 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-2000ExW to 'GND' terminal. Then, turn off
the J1 jumper.
[Figure 9. 4-20mA 3Wire Sink Configuration]
5.3. Installation Cable Length
■ The maximum length between GTD-2000ExW 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-2000ExW
·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-2000ExW minimum operating voltage = 18 Vdc
·VMAXDROP = 24 - 18 = 6V
·IMAX = 0.2A (200mA)
·6 ÷ 0.2 ÷ 0.01318 ÷ 2 = 2276m ≒ 2.000m
■ 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
2879
14
2.08
0.00828
1811
16
1.31
0.01318
1138
18
0.82
0.02095
715
20
0.518
0.0333
450
[Figure 10. Calculation of GTD-2000ExW Installation Cable Length]
[Table 4. GTD- 2000ExW Power Cable Installation Length]