Rockwell Automation 1760-xxxx Pico Controller User Manual - Manual (Page 182)

Publication 1760-UM001D-EN-P - September 2005
9-4 Use of Expansion Modules
Monitor for Short Circuit or Overload
Expansion module 1760-IB12XOB8 provides 8 transistor outputs. The
outputs are thermally protected, and switch off in the event of an
overload or short circuit. After a cooling period, a faulted output
re-energizes in an attempt to operate the output load. If the fault
condition still exists, the output will overheat and switch off again.
This process is repeated until the overload is removed (or until power
is turned off).
You can use internal inputs R15 and R16 to monitor for short circuits
or overloads on an output. Each of the bits (R15 and R16) monitors a
group of four outputs.
• R15: Group fault signal for outputs S5 to S8
• R16: Group fault signal for outputs S1 to S4
The bit is active (1) when one or more of the outputs in the group has
been faulted. An overload fault is indicated as follows.
If the Status is: Then:
R15 R16
0 0 No overload.
0 1 At least one output has a fault in Group S1 to S4.
1 0 At least one output has a fault in Group S5 to S8.
1 1 At least one output has a fault in each Group.
IMPORTANT
Monitor these bits (R15 and R16) in your logic
program to be sure that system or machine
operations are handled in an orderly manner in the
event of an output fault.