ICP DAS USA I-7521 User Manual page 20

Pin assignment of bottom 14-pin screw terminal block (I-7524/
I-7524D):
Pin Name Description
1 DO 100 mA, 30V max.
2 DI 3.5V ~ 30V
3 D1+ DATA+ pin of COM1 (RS-485)
4 D1- DATA - pin of COM1 (RS-485)
5 CTS1 Clear To Send of COM1 (RS-232)
6 RTS1 Request To Send of COM1 (RS-232)
7 GND Signal ground of RS-232
8 TXD1 Transmits Data of COM1 (RS-232)
9 RXD1 Receives Data of COM1 (RS-232)
10 INIT* Initial pin, 3.5V ~ 30V
11 D2+ DATA+ pin of COM2 (RS-485)
12 D2- DATA - pin of COM2 (RS-485)
13 +VS V+ of power supply (+10 to +30VDC unregulated)
14 GND GND of power supply
Note: The COM1 can be used as a RS-232 port or a RS-485 port. It is
not recommended to use both RS-232 & RS-485 at the same time.
Pin assignment of top 14-pin screw terminal block:
15 CTS3 CTS pin of COM3 (RS-232)
16 RTS3 RTS pin of COM3 (RS-232)
17 TXD3 TXD pin of COM3 (RS-232)
18 RXD3 RXD pin of COM3 (RS-232)
19 GND GND pin of COM3/COM4 (RS-232)
20 CTS4 CTS pin of COM4 (RS-232)
21 RTS4 RTS pin of COM4 (RS-232)
22 TXD4 TXD pin of COM4 (RS-232)
23 RXD4 RXD pin of COM4 (RS-232)
24 GND GND pin of COM4/5 (RS-232)
25 CTS5 CTS pin of COM5 (RS-232)
26 RTS5 RTS pin of COM5 (RS-232)
27 TXD5 TXD pin of COM5 (RS-232)
28 RXD5 RXD pin of COM5 (RS-232)
I-7521/I-7522/I-7522A/I-7523/I-7524/I-7527 User's Manual,Ver2.5 Aug.2015
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