Honeywell HC900 - Page 181

Diagnostics and Troubleshooting - Controller CPU indicators
Revision 19 HC900 Process Controller Installation and User Guide 169
06/14
Number
of Red
Strobes
Possible Causes Lead and/or Reserve Controller
Action(s)
User Action Honeywell OI
Indication
HCDesigner/HC
Utilities Indication
8 or 9 If 8 flashes, the S1
serial port is reporting a
diagnostic.
If 9 flashes, the S2
serial port is reporting a
diagnostic.
Possible causes are:
• If the port is
configured as a
Modbus or ELN
slave, the data link
layer is reporting
that at least 75% of
the last characters
received have had
a failure reported by
the UART or at
least 75% of the
last messages
received have
been invalid.
• If the port is
configured as a
Modbus Master, at
least 75% of the
last requests to a
particular slave
resulted in no
response or a reply
that failed the data
link protocol.
1. ASYS and FSYS blocks’ HW
OK pins are turned off.
2. If configured as a Modbus
master:
• ASYS and FSYS blocks’
Modbus Master Fail pins are
turned on.
• Slave and read blocks
associated with the slaves
experiencing the failure have
their read pins frozen to the last
value read.
• Slave blocks associated with
the slaves experiencing the
failure have their BAD COMM
and NO SCAN pins turned on.
• IN SCAN STATUS is set to
NO for all slaves experiencing
the failure.
• COMM STATUS is set to BAD
for all slaves experiencing the
failure.
• The slaves with the data link
errors have a non-zero data
link error count.
• The slaves experiencing the
failure are moved to the
background scan rate.
1. Check baud rate
2. Check connectors
3. Check cable polarity
4. Isolate cabling from electrical
interference
5. If RS-232 to RS-485 converter is
used, check its power, switch/jumper
settings, and polarity.
6. If configured as a Modbus master,
use the slave status screens to
determine which slaves are
experiencing the problem. For those
slaves check:
• Power
• Connections
• address
• baud rate
• parity
• number of stop bits
• for electrical interference
• grounding
• termination resistor (if at end
of link)
7. The diagnostic is cleared by
clearing the port’s statistics.
The UART failed its
power-up tests
See above Replace CPU module
10 Ethernet port tests
failed during power-up.
1. E1 or E2 port diagnostic is set to
FAILED.
2. ASYS block’s HW OK pin is
turned off.
Replace CPU module. If the lead’s status
LED is indicating
the failure, see
NETWORK
PORT E1 or
NETWORK
PORT E2 in the
“Lead CPU
Diagnostics”
display.
If the reserve’s
status LED is
indicating the
failure, see
NETWORK
PORT E1 or
NETWORK
PORT E2 in the
“Reserve CPU
Diagnostics”
display.
If the lead’s status
LED is indicating
the failure, see
Lead Port E1:
Network Port
Diagnostics or
Lead Port E2:
Network Port
Diagnostics in
the “Lead
Diagnostics
Overview” dialog
box.
If the reserve’s
status LED is
indicating the
failure, Lead Port
E1: Network Port
Diagnostics or
Lead Port E2:
Network Port
Diagnostics in
the “Reserve
Diagnostics
Overview” dialog
box.