C.2 rs-422 cable configuration, C.2.1 rs-422 connection – SATEC SLC500 User Manual
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C.2 RS-422 Cable Configuration
C.2.1 RS-422 Connection
TxD
RxD
TxD-
RxD-
TxD
RxD
6
7
6
2
1
9
RxD'
TxD'
1746-BAS BASIC module
DB9 male connector
DB9 female connector
2
3
Series PM-280/288/270/290
Powermeters
RxD-
TxD-
RxD
TxD
6
7
DB9 male connector
RxD-
TxD-
RxD
TxD
Series PM-290H Powermeters
Series PM-170 Powermeters
8
9
14
15
16
17
DB25 male connector
5
1
1
1
GND
GND
GND
* A termination resistor should only be connected at the furthest end of the cable
COM
R1
R1,R2 - 120
*R2
R3,R4 - 1.2 k
Ω
Ω
**R3
**R4
** In RS-422 communication, a reference or common line should be used in addition to signal lines
** In RS-422 communications, a reference or common line should be used in addition to signal lines for stable operation.
Connect pin 1 (instrument) to pin 5 on the BASIC module. If you do not use a reference line, place pull-down resistors
R3 and R4 on both outputs of the driver to avoid leaving the line floating when the line is idle.