Emerson Rosemount 385, Reference Manual, Page: 25 / 34

Reference Manual Troubleshooting
00809-0100-3385 February 2019
Troubleshooting 19
Section 5: Troubleshooting
Note: For any repair or warranty inquiries please contact our Customer Care group.
Table 5-1: Troubleshooting
Trouble Probable Cause Remedy
Meter reads off scale. (Display
reads overrange.)
Defective preamplifier. Check preamplifier as instructed in Section
4.2.3 and replace preamplifier if defective.
T.C. element shorted. Check T.C. element as instructed in Section
4.2.2 and replace sensor tube if defective.
Electrode not in solution or sample.
or stream is not full.
Make sure sensor is in solution that sample
stream is full (see Section 2.0 for installation)
Open glass electrode. Replace sensor tube.
Display reads between 3 and 6
pH regardless of actual pH of
solution or sample.
Electrode cracked. Replace sensor tube.
Meter or display indication
swings or jumps widely in
AUTO T.C. Mode.
T.C. element shorted. Check T.C. element as instructed in Section
4.2.2 and replace sensor tube if defective.
Span between buffers
extremely short in AUTO T.C.
Mode.
T.C. element open. Check T.C. element as instructed in Section
4.2.2 and replace sensor tube if defective.
Sluggish or slow meter
indication for real changes in
pH level.
Electrode coated. Clean sensor as instructed in Sections 4.2.1 or
4.4.2.
Electrode defective. Replace sensor tube.
Transmitter cannot be
standardized.
Electrode coated or cracked. Clean sensor as instructed in Sections 4.2.1 or
4.4.2 and, if cracked,replace sensor tube.
Defective preamplifier. Check preamplifier as instructed in Section
4.2.3 and replace preamplifier if defective.
Transmitter short spans
between two different buffer
values.
Old glass electrode (greater than 1 year old). Replace sensor tube.
Coated glass. Clean Sensor as instructed in Sections 4.2.1 or
4.4.2.
5.1 Troubleshooting