Rockwell Automation 1747-L5xx SLC 500 Modular Hardware Style User Manual User Manual
Page 148
Publication 1747-UM011G-EN-P - June 2008
148
Troubleshooting
Identifying SLC 5/02 Processor Communication Errors
SLC 5/02 Processor Communication Errors
If the status indicators
indicate
The following
error exists
Probable Cause
Recommended Action
•
Power status indicator is
on
•
Comm status indicator is
off
•
CPU Fault status
indicator is off or
flashing
•
Status of Run, Forced
I/O, and Battery Low
status indicators does
not matter
The SLC 5/02
processor is not
receiving data and
is not
communicating
with the
programmer
DH-485
communication
parameters are
improperly set up.
1. Check communication parameters of programmer.
Programmer and processor communication rate must match.
Programmer and processor node addresses must be
different.
2. Try different combinations of:
a. communication rate (default is 19.2 K)
b. node address (default is 1)
3. Try to increase the maximum node address.
(default is 31)
Bad connection of
communication
device.
1. Check cable continuity.
2. Check cable connections between programmer and
processor.
3. Check communication device (for example, the 1747-PIC
interface). Replace if necessary.
Low or no power to
communication
device.
1. Verify proper power supply selection and backplane loading.
(The 1747-PIC and 1747-AIC interface draw power off the
backplane.)
2. Verify proper 120/240V power supply jumper selection. See
•
Power status indicator is
on
•
Comm status indicator is
on
•
CPU Fault status
indicator is off or
flashing
•
Status of Run, Forced
I/O, and Battery Low
status indicators does
not matter
The SLC 5/02
processor is
receiving data, but
is not
communicating
with the
programmer
DH-485
communication
parameters are set
up improperly.
1. Check communication parameters of programmer.
Programmer and processor communication rate must match.
Programmer and processor node addresses must be
different.
2. Try different combinations of:
a. communication rate (default is 19.2 K)
b. node address (default is 1)
3. Try to increase the maximum node address.
(default is 31)
•
Power status indicator is
on
•
CPU Fault status
indicator is on
•
Status of all other status
indicators does not
matter
A fatal error has
occurred
Excessive noise or
a faulty SLC 5/02
processor.
1. Cycle power to obtain flashing CPU Fault status indicator and
default program.
2. Examine the error code following the power cycle. Take
appropriate action.
3. Reload the program.
4. Contact your local Rockwell Automation representative if the
error persists.