American Magnetics 185 & 186 Liquid Level Instruments (CE-Marked) - Manual (Page 79)

Rev. 3 69
Appendix
RS-232 cable DB-25 to DB-9 translation
A.3 RS-232 cable DB-25 to DB-9 translation
All other pins on the DB-25 connector are unused. This is standard PC
modem cable wiring.
A.4 RS-422 Cable Wiring
DB-25 Pin DB-9 Pin
2 3
3 2
4 7
5 8
6 6
7 5
8 1
20 4
22 9
13X/18X
INSTRUMENT
EIA-530
DEVICE
13X/18X CONNECTOR EIA-530 CONNECTOR
RX+ (PIN 2) TX+ (PIN 14)
TX+ (PIN 3)
TX- (PIN16)
RX- (PIN 21)
TWISTED PAIR
TWISTED PAIR
TX- (PIN 2)
RX+ (PIN 16)
RX- (PIN 3)
RX+
RX-
TX-
TX+
EARTH GROUND
(SHOWN FOR
REFERENCE ONLY;
CONNECTED TO
INSTRUMENT
CHASSIS AND TO
AC MAINS "EARTH"
CONDUCTOR)
SIGNAL GROUND
(SHOWN FOR
REFERENCE ONLY;
CONNECTED TO
INSTRUMENT RS-422
DRIVER/RECEIVER
CIRCUIT GROUND)
DB25 FEMALE
13
25
12
24
11
23
10
22
9
21
8
20
7
19
6
18
5
17
4
16
3
15
2
14
1
DB25 MALE
13
25
12
24
11
23
10
22
9
21
8
20
7
19
6
18
5
17
4
16
3
15
2
14
1