Matching SDM‑SIO1A connections to an SDM‑SIO1
This section is provided for users who are familiar with the older SDM-SIO1, so they can cross reference connections between the new and old devices.
The SDM‑SIO1A has fewer terminals and different labeling than the SDM-SIO1. It does, however, perform in exactly the same way and can be used as a drop-in substitute with only minor changes to the wiring. It has fewer terminals because the Z, Y, B, and A terminals are not present. For the SDM-SIO1 these terminals were connected internally to the Tx, RTS, CTS and Rx terminals respectively and were, therefore, duplicates. RS-422 and RS-485 devices can be connected to the equivalent multifunction terminals on the SDM‑SIO1A.
The labeling for the RS-422/RS-485 functions has also been changed to avoid the confusion caused by different labeling conventions used for the A and B terminals by different manufacturers. To avoid this, the SDM‑SIO1A uses the alternative TD–, TD+, RD–, RD+ scheme of labeling, with the TD– and TD+ pair being those used for RS-485 half-duplex connections. Please refer to Pin cross connection table for SDM-SIO1 to SDM‑SIO1A for a cross comparison between the connections for the SDM-SIO1 and the SDM‑SIO1A.
|
SDM-SIO1 |
SDM‑SIO1A |
||
|---|---|---|---|
|
Case text |
Pin |
Pin |
Case text |
|
C1 |
1 |
3 |
C1 |
|
C2 |
2 |
4 |
C2 |
|
C3 |
3 |
5 |
C3 |
|
G |
4 |
2 |
G |
|
+12V |
5 |
1 |
+12V |
|
G |
6 |
7 |
G |
|
RX-A |
7 |
10 |
Rx/RD+ |
|
CTS-B |
8 |
11 |
CTS/RD– |
|
RTS-Y |
9 |
8 |
RTS/TD+ |
|
TX-Z |
10 |
9 |
Tx/TD– |
|
0V |
11 |
6 |
RG |
|
Z |
12 |
9 |
Tx/TD– |
|
Y |
13 |
8 |
RTS/TD+ |
|
B |
14 |
11 |
CTS/RD– |
|
A |
15 |
10 |
Rx/RD+ |