Emerson Rosemount CCO 5500, Reference Manual

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6 Troubleshooting
6.1 Finding faults with the keypad
WARNING!
ELECTRIC SHOCK
Install all protective equipment ground covers and safety ground leads after troubleshooting.
Failure to install covers and ground leads could result in serious injury or death.
If a fault occurs, the control unit display switches from its current mode of operation to the
DIAGNOSTICS mode and displays the current fault condition. Refer to Section 6.1.1 for
further information on the fault conditions. If the fault clears, the display stays in
DIAGNOSTICS mode and displays
All Clear
.
Enter DIAGNOSTICS mode from the instrument's keypad; you can do this at any time
without interrupting or disturbing the analog outputs of the equipment. As an initial guide
to equipment performance, typical values for instrument operation are given below.
D2 min D2 max D1 min D1 max Set Cal min Set Cal max
Rosemount
™
CCO 5500
3,000 20,000 3,000 20,000 2,000 2,900
where:
Modulation frequency = 30 to 45 Hz
Mark/space ratio = 0.9 to 1.1
Saturation count = 50 maximum for all analyzers
If the values are outside of the above ranges, the Data valid LED extinguishes, and the fault
condition is displayed.
6.1.1 Data valid LED out
If one or more fault conditions occur, the data valid LED on the front panel extinguishes,
the data valid relay operates, and the instrument automatically enters the
DIAGNOSTICS
mode to display the fault condition.
Fault Conditions Table 6-1:
Fault condition Possible causes
Detector signal saturated (Sat # over 50) Incorrect detector gain adjustment.
Troubleshooting
Reference Manual 91