Emerson Rosemount FCL Reference Manual page 43

Reference Manual
00809-0200-3412
4. Remove the fill plug.
5. Allow the electrolyte solution to drain out.
6. Inspect the cathode.
7. Wrap the plug with two turns of pipe tape and set aside.
8. Prepare a new membrane.
9. Hold the sensor at about a 45° angle with the cathode end pointing up.
10. Add electrolyte solution through the fill hole until the liquid overflows.
11. Tap the sensor near the threads to release trapped air bubbles.
12. Add more electrolyte solution if necessary.
13. Place the fill plug in the electrolyte port and begin screwing it in.
14. After several threads have engated, rotate the sensor so that the cathode is
15. Place a new O-ring in the groove around the cathode post.
16. Cover the holes at the base of the cathode stem with several drops of electrolyte
17. Insert a small blunt probe, like a toothpick with the end cut off, through the
18. Gently press the probe against the bladder several times to force liquid through the
19. Place a drop of electrolyte solution on the cathode; then place the membrane
Rosemount FCL 56
a) If it is tarnished, clean it using a cotton-tipped swab dipped in baking soda or
alumina.
Use type A dry powder alumina intended for metallographic polishing of
medium and soft metals.
b) Rinse thoroughly with water.
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) Wait for the wooden ring to soak up the solution.
This usually takes several minutes.
pointing up and continue tightening the fill plug.
Do not overtighten.
solution.
pressure equalizing port.
CAUTION
Equipment damage
A sharp probe may puncture the bladder and destroy the sensor.
Do not use a sharp probe.
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.
assembly over the cathode.
Maintenance
May 2019
43