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17
GTD-5000F
Instruction Manual
5. Installation
5. Installation
5.4. RS-485 Terminal Configuration
Device Terminal Name
Master Terminal Name
Notes
RS485A
'TRXD+' or 'A' or 'P'
RS485B
'TRXD- or 'B' or 'N'
■ Connect RS-485A and RS-485B of CN17 with MODBUS Master terminal as shown below.
Note1) Use cable designated for RS-485
Note 2) When there is no RS485 option available for GTD-5000F, the following function does not run.
[Table 3. GTD-5000F Power Cable Installation Length]
AWG
mm
2
COPPER RESISTANCE(ohms/m)
METERS
12
3.31
0.00521
1046
14
2.08
0.00828
658
16
1.31
0.01318
413
18
0.82
0.02095
260
20
0.518
0.0333
163
5.5. Installation Cable Length
[Figure 8. GTD-5000F Installation Cable Length Calculation]
■ The maximum length between GTD- 2000Tx 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-5000F minimum operating voltage = 18 V DC
·
VMAXDROP = 24 - 18 = 6V
·
IMAX = 0.55A ( 550mA )
·
6 ÷ 0.55 ÷ 0.01318 ÷ 2 = 413.8502m ≒ 413m
Power cable installation for each cable type is as shown in the table below.
