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5. Installation
[Figure 9. 4-20mA 3Wire Sink Configuration]
5.3.3. 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-
2000TxW to'GND' terminal. Then, turn off the J1 jumper.
5.4. Installation Cable Length
■ The maximum length between GTD-2000TxW 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-2000TxW
·
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-2000TxW minimum operating voltage = 18 Vdc
·
VMAXDROP = 24 - 18 = 6V
·
IMAX = 0.15A( 150mA )
·
6 ÷ 0.15 ÷ 0.01318 ÷ 2 = 1,517.451m ≒ 1,517m