Rockwell Automation 1771-IS 5V DC INPUT MOD - Manual (Page 12)

Module Preparation, Wiring and
Installation
Chapter 2
2-5
removed or installed in the I/O rack without disconnecting the wiring.)
The swingarm can be removed from the I/O rack at the pivot bar.
Thumbwheel Switch Wiring
Thumbwheel switch terminations are illustrated in Figure 2.3. Digit place
labels refer to the position of each digit in a 3-digit or 4-digit thumbwheel
switch as follows:
MSD and LSD - Most and Least Significant Digit; MD Middle Digit;
UMD and LMD - Upper and Lower Middle Digit, respectively.
Thumbwheel switches are wired in parallel as shown in Figure 2.4 for
4-digit switches, and in Figure 2.5 for 3-digit switches. The four switch
terminals numbered 8, 4, 2, 1 for each thumbwheel digit are wired
respectively to field wiring arm terminals 2, 3, 4, 5 or 6, 7, 8, 9. Field
wiring arm terminal 1 is not used.
Figure 2.3
Thumbwheel Terminations
MSD
8
4
2
1
UMD
8
4
2
1
LMD
8
4
2
1
LSD
8
4
2
1
MSD
8
4
2
1
MD
8
4
2
1
LSD
8
4
2
1
4–Digit
Thumbwheel
3–Digit
Thumbwheel
Digit Place Labels
Enable Lines
Digit Place Labels
Enable Lines
Switch Terminal
Numbers
Switch Terminal
Numbers
10364