Acksys MI400 Series, Technical Documentation Manual

Page: 74 / 80

FULL-DUPLEX
( POLLING - SELECTING )
RS422A INTERFACE FOR
POINT TO POINT OR MULTIPOINT
MASTER/SLAVE TYPE CONNECTION
FULL-DUPLEX
RS422A INTERFACE FOR
POINT TO POINT OR MULTIPOINT
MASTER TYPE CONNECTION
SIMPLEX
RS422A INTERFACE FOR
POINT TO POINT OR MULTIPOINT
SLAVE TYPE CONNECTION
SIMPLEX
RS422A CONNECTION ( 4 WIRES )
RS422A INTERFACE FOR
POINT TO POINT OR MULTIPOINT
MASTER TYPE CONNECTION
D
A
B
+TX
-TX
R
D
R
A’ +RX A’
A
B
+TX
-TX
+RX
D
R
A’
A
B
+TX
-TX
+RX
-RX
GND
DE
B’ B’
-RX
GND
B’
-RX
GND GND
RS485 WIRES ( 2 WIRES )
HALF-DUPLEX
( POLLING - SELECTING )
RS485 INTERFACE FOR
POINT TO POINT OR MULTIPOINT
MASTER/SLAVE TYPE CONNECTION
HALF-DUPLEX
POINT TO POINT OR MULTIPOINT
( COLLISION DETECTION )
RS485 INTERFACE FOR
MULTIMASTER TYPE CONNECTION
WITH ECHO
22-24 GAUGE AWG
TYPE OF CONNECTION CABLE :
SHIELDED OR UNSHIELDED TWISTED PAIR(s)
NOMINAL IMPEDANCE 100-120 OHMS
CAPACITY BETWEEN CONDUCTORS 50 pF
+RX
-RX
+TX/
-TX/
GND
CONNECT IT TO THE GROUND ON ONE SIDE ONLY.
THE GROUND CONNECTION MUST BE MADE WITH EITHER A WIRE
SHIELDED CABLE IS REQUIRED IN VERY NOISY ENVIRONMENTS;
CAPACITY BETWEEN SHIELDING AND CONDUCTORS 70pF MAX
COMMON TO ALL THE INTERFACES OR BY A GROUND
DE /REB
D
R
A-A’
B-B’
+RX
-RX
GND
DE /REB
D
R
A-A’
B-B’
+TX/
-TX/
+TX/
RS422A
RS485
TERMINATION RESISTOR
+RX
+RX
RS422A
RS485
BIAS
+RX +TX/
+RX
( SAME GROUND REFERENCE FOR ALL EQUIPMENTS ).
CONNECTION FOR EACH INTERFACE.
IF GALVANICALLY ISOLATED INTERFACES ARE USED,
THE GROUND CONNECTION IS NOT REQUIRED.
THE COMMON MODE VOLTAGE IS LIMITED TO THE VOLTAGE
CORRESPONDING TO THE GALVANIC ISOLATION.
-RX -TX/
-RX
VCC
560 ohms max in RS485 mode
1 Kohms max in RS422A mode
-RX
-RX -TX/
TR
100-120 ohms
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