Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal - Manual (Page 407)

Chapter 28
Troubleshooting Faults
28–5
Error Code
(Hex)
Description Probable Cause Recommended Action
0021 A remote power failure of an expansion I/O
rack has occurred.
Note: A modular system that encounters
an overvoltage or overcurrent condition in
any of its power supplies can produce any
of the I/O error codes listed on pages 28–8
to 28–10 (instead of code 0021). The
overvoltage or overcurrent condition is
indicated by the power supply LED being
off.
ATTENTION: Fixed and FRN 1 to 4
SLC 5/01 processors – If the
remote power failure occurred
while the processor was in the Run
mode, error 0021 will cause the
major error halted bit (S:1/13) to be
cleared at the next powerup of the
local rack.
SLC 5/02 processors and FRN 5
SLC 5/01 processors – Power to
the local rack does not need to be
cycled to resume the Run mode.
Once the remote rack is
re-powered, the CPU will restart
the system.
!
Fixed and FRN 1 to 4 SLC 5/01
processors: Power was removed or the
power dipped below specification for an
expansion rack.
SLC 5/02 processors and FRN 5 and
higher SLC 5/01 processors: This error
code is present only while power is not
applied to an expansion rack. This is the
only self-clearing error code. When power
is re-applied to the expansion rack, the
fault will be cleared.
Fixed and FRN 1 to 4 SLC 5/01
processors: Cycle power on the local
rack.
SLC 5/02 processors and FRN 5 and
higher SLC 5/01 processors: Re-apply
power to the expansion rack.
0022 The user watchdog scan time has been
exceeded.
•
Either Watchdog time is set too low for
the user program, or
•
user program caught in a loop.
•
Either increase the watchdog timeout in
the status file (S:3H), or
•
correct the user program problem.
0023 Invalid or non-existent STI interrupt file.
•
Either an STI interrupt file number was
assigned in the status file, but the
subroutine file was not created, or
•
the STI interrupt file number assigned
was 0, 1, or 2.
•
Either disable the STI interrupt setpoint
(S:30) and file number (S:31) in the
status file, or
•
create an STI interrupt subroutine file
for the file number assigned in the
status file (S:31). The file number must
not be 0, 1, or 2.
0024 Invalid STI interrupt interval. The STI setpoint is out of range (greater
than 2550 ms, or negative).
•
Either disable the STI interrupt setpoint
(S:30) and file number (S:31) in the
status file, or
•
create an STI interrupt routine for the
file number referenced in the status file
(S:31). The file number must not be 0,
1, or 2.
0025 Excessive stack depth/JSR calls for the
STI routine. A JSR instruction is calling for a file
number assigned to an STI routine. Correct the user program to meet the
requirements and restrictions for the JSR
instruction, then reload the program and
run.