Chapter 5 Troubleshooting - Emerson Rosemount 389 Reference Manual

Reference Manual
00809-0100-3389
5 Troubleshooting
Table 5-1: Troubleshooting
Trouble
Meter reads off scale (Display reads
overrange).
Display reads between 3 and 6 pH
regardless of actual pH of solution or
sample.
Meter or display indication swings or
jumps widely in AUTO T.C. Mode.
Span between buffers extremely short
in AUTO T.C. Mode.
Sluggish or slow meter indication for
real changes in pH level.
Transmitter cannot be standardized.
Transmitter short spans between two
different buffer values.
Reference Manual
Probable Cause
Defective preamplifier.
T.C. element shorted
Sensor not in process or sample
stream is low.
Open glass electrode.
Reference element open - no contact.
Electrode cracked.
T.C. element shorted.
T.C. element shorted.
Electrode cracked.
Electrode defective.
Electrode coated or cracked.
Defective preamplifier
Old glass electrode or high
temperature exposure.
Coated glass.
Troubleshooting
February 2019
Remedy
Replace preamplifier (for code 02
sensors). For code 01, replace sensor.
Check T.C. element as instructed in
Automatic temperature compensator
and replace sensor if defective.
Make sure sensor is in process with
sufficient sample stream (refer to
Install for installation details).
Replace sensor.
Replace sensor.
Replace sensor.
Check T.Cl. element as instructed in
Automatic temperature compensator
and replace sensor if defective.
Check T.Cl. element as instructed in
Automatic temperature compensator
and replace sensor if defective.
Clean sensor as instructed in
electrode or Cleaning platinum
electrode. Replace sensor if cracked.
Replace sensor.
Clean sensor as instructed in
electrode or Cleaning platinum
electrode. Replace sensor if cracked.
Replace preamplifier.
Replace sensor.
Clean sensor as instructed in
electrode or Cleaning platinum
electrode. Replace sensor if cracked.
Clean
Clean
Clean
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