Allen-Bradley SLC 500, User Manual, Page: 167 / 294

Publication 1747-UM011G-EN-P - June 2008
Troubleshooting
167
Off On/energized Your output
device will not
turn off and the
program
indicates that it
is off.
Output device is
incompatible.
Check specifications.
Output circuit off-state
leakage current may
exceed output device
specification.
Check specifications. Use load resistor to bleed off
leakage current. See output specifications.
Incorrect wiring. Check wiring. Disconnect from SLC processor and verify
device operation.
Output device is
shorted or damaged.
Verify device operation. Replace device.
Output circuit is
damaged.
Check wiring. Try other output circuit. Replace module.
Off/de-energized Your program
indicates that the
output circuit is
on or the output
circuit will not
turn on.
Programming problem. Check for duplicate outputs and addresses using search
function.
If using subroutines, outputs are left in their last state
when not executing subroutines.
Use the force function to force output on. If this does not
force the output on, output circuit is damaged. If the output
does force on, then check again for logic/programming
problem.
Output is forced off in
program.
Check processor FORCED I/O or FORCE status indicator and
remove forces.
Output circuit is
damaged.
Use the force function to force the output on. If this forces
the output on, then there is a logic/programming problem.
If this does not force the output on, the output circuit is
damaged. Try other output circuit. Replace module.
If your
Output
Circuit
status
indicator
is And your output
device is And Probable Cause Recommended Action