MODEL 54eA

SECTION 16.0

 

TROUBLESHOOTING

SECTION 16.0

TROUBLESHOOTING

16.1 OVERVIEW

The 54eA controller continuously monitors itself and the sensor for faults. When the controller detects a fault in the amperometric or pH sensor or in the instrument itself it displays a fault message. If alarm 4 was enabled, the red FAIL LED will also light and relay 4 will activate. The outputs will go to 22.00 mA or to the value programmed in Section 5.6.

Special rules apply to pH sensor diagnostics (high and low glass impedance). Alarm 4, the FAIL LED, and the out- put current failure mode will operate only if pH sensor diagnostics have been enabled. See Section 5.8.

See Section 16.2 for an explanation of fault messages and suggested corrective actions.

The controller also displays error and warning messages if a calibration is seriously in error. Refer to the section below for assistance. Each section also contains hints for correcting other measurement and calibration problems.

 

Measurement

Section

 

Temperature

15.3

 

 

Dissolved oxygen

15.4

 

 

Free chlorine

15.5

 

 

Total chlorine

15.6

 

 

Monochloramine

15.7

 

 

Ozone

15.8

 

 

pH

15.9

 

 

 

 

 

For troubleshooting not related to measurement problems, see Section 16.10.

To view diagnostic variables, go to the main display and press any key. Move the cursor to “Diagnostic variables” and press Enter (F4). Use the é or ê key to move up or down the list.

16.2 TROUBLESHOOTING WHEN A FAULT MESSAGE IS SHOWING

 

 

Fault message

Explanation

See Section

 

 

High input current

input current exceeds 210 uA

16.2.1

 

 

 

Check sensor zero

sensor current was too high when sensor was zeroed

16.2.2

 

 

 

pH low input voltage

input voltage is less than -1400 mV

16.2.3

 

 

 

pH high input voltage

input voltage exceeds 1400 mV

16.2.3

 

 

 

pH low reference voltage

input voltage is less than -1600 mV

16.2.4

 

 

 

pH high reference voltage

input voltage exceeds 1600 mV

16.2.4

 

 

 

Old glass warning

glass impedance exceeds high limit

16.2.5

 

 

 

Cracked glass failure

glass impedance is less than low limit

16.2.6

 

 

 

Temp error low

temperature less than -15°C

16.2.7

 

 

 

Temp error high

temperature greater than 130°C

16.2.7

 

 

 

Sense line open

RTD sense line is open

16.2.8

 

 

 

Failure factory

instrument needs factory calibration

16.2.9

 

86

 

Failure eeprom

write verify error has occurred

16.2.9

 

 

 

 

 

 

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Emerson Process Management 53eA Section Troubleshooting, Overview, Troubleshooting When a Fault Message is Showing