Rockwell Automation 1771-PM , D17716.5.18 U MNL 1771-PM CLUTCH/BRAKE MOD - Manual (Page 61)

Field Wiring Arm Connections
Chapter 6
6Ć9
Use auxiliary valve solenoids when you want to boost the volume of air to
the clutch/brake assembly. Do this by placing auxiliary valves in parallel
with main valves in your high pressure air line.
If you use auxiliary valves, connect auxiliary valve solenoids A and B
shown in Figure 6.3 for ungrounded solenoids, or Figure 6.7 for grounded
solenoids. If you don’t use one or both auxiliary valve solenoids, you
must connect a 2k ohm, 15W resistor in place of each. Figure 6.3 or
Figure 6.7 also shows connections for:
feedback from auxiliary valve solenoid triacs that allows both voting
processors to monitor the on or off state of each triac, and check for
shorted or open triacs and shorted or open auxiliary valve solenoids.
load resistors, LRA and LRB, for triac feedback from auxiliary valve
solenoids.
Each auxiliary valve solenoid should draw at least 60mA. If not, connect
an appropriate load resistor in parallel with it. For neatness and safety, we
recommend that you connect the feedback resistor and the load resistor
only at convenient terminal strips, not at the field wiring arms.
If you use auxiliary valves with internal fault detection (no valve stem
switches) but you have configured for external fault detection, simulate
the inputs of the auxiliary valve stem switches. Do this by jumpering the
input terminals of field wiring arms for auxiliary valve stem switches to
the input terminals for the main valve stem switches. Jumper terminal 7
to terminal 0, module group 2, slot 0, for chassis A and B (Figure 6.2).
Use optional dump valves and solenoids when you want to accelerate the
evacuation of air from the clutch/brake assembly.
If you use dump valves, install two output modules (cat. no. 1771-OD,
series C or later). Place them in module group 4, slot 0, chassis A and B
to control the dump valve solenoids. Also install two input modules (cat.
no. 1771-IA). Place them in module group 4, slot 1, chassis A and B to
monitor feedback inputs from the dump valve solenoids. Set
configuration bit 14 unconditionally as shown in Figure 4.3, Figure 4.4 or
Figure 4.5.
Connect dump valve solenoids and valve stem switches (if you use them)
as shown in Figure 6.4 for ungrounded solenoids, or Figure 6.8 for
grounded solenoids.
Optional Auxiliary Valve
Solenoids
Optional Dump Valve Solenoids