R500
April 2017
Series 8 C300 Controller User's Guide
Honeywell
255
10. C300 Controller Troubleshooting
10.9. Fault classifications
Table 14.) An indicator next to each condition shows when the soft failure condition
is present.
The Control Builder monitor tab, soft failure in the controller is denoted by a
controller icon with a small red circle with an 'x' inside the circle.
Soft Failure alarm return to normal
The alarm will return to normal once the on-line diagnostics detect that the soft failure
condition has been corrected. Note that on-line diagnostics run on a cycle and hence it
may take a period of time for the controller to perform the subsequent diagnostic check
for the condition, notice the change and then record it.
In some cases, online diagnostics may continue to assert the soft failure condition even
when it appears to have been corrected. This may happen when one occurrence of the
soft failure is considered sufficient to require action that requires replacement of
hardware. When the controller hardware is replaced, the alarm will return to normal
once the C300 Controller function block is deleted and reloaded.
Installation-Startup Failures
A fault that is detected during the C300 Controller's startup or Power-On Self Test
(POST) may prevent the controller from entering an operational state. The C300
Controller module executes a boot program and POST automatically when power is
applied to the controller module. These tests, verify the presence and integrity of the
controller module hardware. Refer to the section
for more details
on startup and POST. Also, refer the section
for details on abnormal startup conditions and corrective actions to
clear them.
If a fault is detected during POST, the controller halts and shows the number of the test
that the controller was performing when it detected the fault on the faceplate display,
(Tnnn). Reset the controller by shorting the two RESET contacts on the controller
IOTA. If the fault persists, replace the controller module since a hardware failure is
indicated. Refer to the section
C300 Controller module and IOTA replacement
for
details.
A redundant controller that fails during startup or POST will not begin control or join the
FTE network. A backup controller that fails during startup or POST will not complete
initial synchronization with its primary or join the FTE network.
Hardware Watchdog Timer Expired
The watchdog timer in the controller employs an independent hardware circuit to ensure
that the controller and its connected I/O devices are brought to a safe state in case the
