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MODEL 1054B pH/ORP SECTION 8.0
DIAGNOSTICS AND TROUBLESHOOTING
SECTION 8.0
DIAGNOSTICS AND TROUBLESHOOTING
8.1 DIAGNOSTICS. The Model 1054B has a diag-
nostic feature which automatically searches for fault
conditions that would cause an error in the measured
pH/ORP value. If such a condition occurs, the current
output and relays will act as configured in Section 4.8
and the fault flag and display will flash. A fault code
mnemonic will display at frequent intervals. If more
than one fault condition exists, the display will
sequence the faults at one second intervals. This will
continue until the cause of the fault has been correct-
ed. Display of fault mnemonics is suppressed when in
Set Mode. Selecting the SHO item will display a history
of the two most recent fault conditions unless SHO was
cleared. Refer to Section 4.8C.
NOTE
If the analyzer is in hold and a fault
occurs, the mnemonic HLd will display
during the fault sequence.
8.1.1 Fault Mnemonics. Table 8-1 lists the fault
mnemonics and describes the meaning of each.
8.1.2 Temperature Compensation. T
able 8-2 is a
ready reference of RTD resistance values at various
temperatures. These are used for test and evaluation
of the sensor.
NOTE
Ohmic values are read across the RTD
element and are based on the manu-
facturer’s stated values (±1%). Allow
enough time for the RTD element to
stabilize to the surrounding temperature.
TABLE 8-1. Fault Mnemonics
Display Description
CAL Warning to calibrate or clean sensor.
CHS ROM failure (check sum error) (bad ROM chip).
COP Computer not operating properly.
EEP EEPROM write error (bad EEPROM chip).
FAC Factory calibration required.
inH Input shorted.
inL Sensor miswired.
Display Description
OId Electrode worn out, coated, or non-immersed.
SEn Sensor line error or wire length error.
SHt Glass electrode cracked or broken.
SLP Slope variance error.
tcH/trH High temperature compensation error.
tcL/trL Low temperature or shorted RTD.
Std Standardization error.
TABLE 8-2. RTD Resistance Values
Temperature Resistance
0 °C 100.00 ohms
10 °C 103.90 ohms
20 °C 107.79 ohms
30 °C 111.67 ohms
40 °C 115.54 ohms
50 °C 119.40 ohms
60 °C 123.24 ohms
70 °C 127.07 ohms
80 °C 130.89 ohms
90 °C 134.70 ohms
100 °C 138.50 ohms
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