Rockwell Automation 1747-L40 SLC 500 Fixed Hardware Style - Manual (Page 80)

Chapter 6
Starting Up Your Control System
6–7
10.Observe the output status LED and the output device.
The output status LED should turn on. The output device should be
energized unless you disconnected it to prevent machine motion. It may
be necessary to connect a dummy load to the output to complete this test.
If the LED does not turn on or if the load is not energized, follow the
output troubleshooting steps listed below.
11. Reset the bit value back to zero for the selected address. Both the output
status LED and the output device should de–energize. If the LED does
not turn off or if the load does not de–energize, follow the output
troubleshooting steps listed below.
12.Repeat steps 9 through 11 for all outputs of the selected slot.
13.Repeat steps 8 through 12 for all slots (with outputs) that are a part of the
fixed controller configuration.
Output Troubleshooting Steps
1. Make sure the processor is in the Run mode.
2. Verify that the test rung recommended in the previous section has been
entered correctly.
3. Check the status file I/O slot enable bits. Status file bit S:11/0 represents
the inputs and outputs of the fixed controller. Status file bits S:11/1 and
S:11/2 represent the inputs and outputs (slot 1 and slot 2 respectively) of
the 2–slot expansion chassis. These bits must be set to one, enabling all
your inputs and outputs.
4. Use a programming device to verify that the bit being tested in the output
file tracks the on/off status of the corresponding bit in the bit file.
If the output file does not track the bit file, but your program has been
entered correctly and the I/O are enabled, then your processor is not
functioning properly and should be replaced.
If the output file tracks the bit file, then the processor is functioning
properly and the output command is being sent to either the I/O section of
the fixed controller, or to the output module in the 2–slot expansion
chassis.
5. Check the electrical connections.
A. If the output being tested is in the 2–slot expansion chassis, verify that
the expansion chassis connector is properly mated to the expansion
connector of the fixed controller.
B. Turn off power to the I/O circuits. Verify that power and/or common
connections are made to the proper output circuit terminals.
C. Verify that the power connections are made to the output load device if
they are required.
D. Verify that the output terminal being tested is connected to the correct
termination point of the load device.
E. Check the tightness of all terminals to make certain that all wires are
secure.