Allen-Bradley SLC 500, User Manual, Page: 128 / 294

Publication 1747-UM011G-EN-P - June 2008
128
Starting Up Your Control System
Output Troubleshooting Steps
1. Make sure the processor is in the Run mode.
2. Verify proper addressing of the output test rung from the
previous page.
3. Using a programming device, locate the output data file and bit
data file. See if the status of the associated bits between these
files match.
4. If the status of the bits match in step 3, and if the status of the
output status indicator match the status of the bits,
but the status
of the output device is different, continue to step 5.
If the output status indicator does not match associated bit
status, check status file S:11 and S:12 I/O slot enables. Bits
S:11/0 through S:11/15 and S:12/0 through S:12/14 should all be
1 enabling all I/O slots for the modular system.
If the output slot enable was verified, try exchanging the output
module under test with identical hardware and retest. If the new
hardware works properly, replace the original.
5. Verify proper output voltage at the output terminal and then at
the output device.
6. De-energize the output circuit and check all output circuit
terminations and wire routes.
7. If proper output voltage does not exist at the output device and
the power source is adequate to drive the output device, test the
output device and replace it if necessary.
For more information on output troubleshooting, see page 165.