Emerson Rosemount TCL, Manual

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d. Start the reagent pump and collect reagent for ten minutes.
e. Note the volume of reagent collected in the graduated cylinder. After ten
minutes, the volume should be about 2 mL.
Disconnecting sample (A) and reagent (B) tubing prior to checking flow Figure 11-1:
11.5.4 Process readings are erratic or wander.
1. Is the sensor properly wired to the transmitter? See Section 4.4 . Verify that all
connections are tight.
2. Readings can be erratic when a new sensor is first placed in service. Readings usually
stabilize after about an hour.
3. Is the air pump working? There should be a vigorous stream of bubbles in the flow
cell. The bubbles help mix the sample and keep carbon dioxide bubbles off the
membrane. Carbon dioxide forms when bicarbonate alkalinity in the sample reacts
with acetic acid. The bubbles accumulate in the membrane and eventually break
away, causing the total chlorine reading to wander.
4. Is the membrane damaged or loose? Replace the membrane if necessary.
5. Is the space between the membrane and cathode filled with electrolyte solution,
and is the flow path between the electrolyte reservoir and membrane clear? Refer to
Section 11.5.2 step 3 for information.
Troubleshooting
Instruction Manual 93