Honeywell 9782 Series On-Line Diagnostics and System Error Messages, Output affected by error

Conductivity/Resistivity Analyzer/Controller

9.4 On-Line Diagnostics and System Error Messages

Self-tests at 0.5 second intervals

On-line diagnostics are self-tests which are performed automatically as a background task every 1/2 second. The system error messages (displayed on the alarm stripe if a test is failed) are listed in Table 9-3.

Output affected by error

In an error condition, the Analyzer will continue to perform all the functions it is capable of except that the output signal(s) will go to 0%. (Output signal manipulation does not occur with calibration failure or clock reset diagnostics.)

Table 9-3 On-Line Diagnostics and System Error Messages

SYSTEM ERROR

MESSAGE

A/D CONV FAILURE

CELL 1 OUT OF RANGE

or

CELL 2 OUT OF RANGE

CELL 1 TEMP ERROR

or

CELL 2 TEMP ERROR

CLOCK RESET

EPROM ERROR

RAM DATA CORRUPTED

RAM ERROR

RAM ERROR IN CPU

WHEN

TESTED

background

background

background

after power failure

at reset

background

at reset

at reset

CONDITION

faulty analog-to-digital converter

Cell reading is out of range for either the high or low limit of the selected cell constant. The cell’s display will stop updating until the condition and alarm message clears. Instead, to indicate an invalid display, the display will alternately flash 0.0 and either the last known value or the high end limit for the cell constant.

Cell temperature compensator faulty

Clock is on, but time may be incorrect, or

clock is off as a result of the power failure.

faulty EPROM

data in non-volatile memory has been changed by a fault

faulty RAM

faulty RAM in microprocessor

CORRECTIVE

ACTION

Have instrument serviced.

Check cell to make sure it is connected to terminals. Make sure cell constant is correct for expected conductivity range.

Check cell (see Note 1).

Reset the time, or

if clock is off, turn it on and reset the time.

Have instrument serviced.

Power down, check power supply and wiring for high voltage spikes. Have instrument serviced, if necessary.

Have instrument serviced.

Have instrument serviced.

Note 1: Temperature compensator should be 8550 ohms at 25 °C. If temperature compensator fails, a conductivity instrument will be forced to its display range high limit. A resistivity instrument will be forced to the low end of the range or zero.

9-4 9782 Series Conductivity/Resistivity Analyzer/Controller - Operator’s Manual 7/99