Emerson Rosemount 499ADO, Quick Start Manual

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8. Wrap the plug with one or two turns of pipe tape.
9. Prepare a new membrane.
a. Hold the membrane assembly with the cup formed by the membrane and
membrane holder pointing up.
b. Fill the cup with electrolyte solution.
c. Leave the membrane assembly filled with electrolyte solution and set it aside.
10. Hold the sensor at about a 45° angle with the cathode end pointing up.
11. Add electrolyte solution through the fill hole until the liquid overflows.
12. Tap the sensor near the threads to release trapped air bubbles.
13. Add more electrolyte solution if necessary.
14. Place the fill plug in the electrolyte port and begin screwing it in.
15. After several threads have engaged, rotate the sensor so that the cathode is
pointing up and continue tightening the fill plug.
Do not overtighten.
16. Place a new O-ring in the groove around the cathode post.
17. Cover the holes at the base of the cathode stem with several drops of electrolyte
solution.
18. Insert a small blunt probe, like a toothpick with the end cut off, through the pressure
equalizing port.
See Figure 1-1 .
CAUTION!
EQUIPMENT DAMAGE
Do not use a sharp probe. It will puncture the bladder and destroy the sensor.
19. Gently press the probe against the bladder several times to force liquid through the
holes at the base of the cathode stem. Keep pressing the bladder until no air bubbles
can be seen leaving the holes. Be sure the holes remain covered with electrolyte
solution.
20. Place a drop of electrolyte solution on the cathode; then place the membrane
assembly over the cathode.
21. Screw the membrane retainer in place.
The sensor may require several hours operating at the polarizing voltage to
equilibrate after the electrolyte solution has been replenished.
Maintenance
20 Rosemount 499ADO