Emerson Rosemount MCL-220 Manual page 67

3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
Table 8-1:
Part number
23750-00
9550094
33521-00
23501-09
23502-09
9210732
Instruction Manual
Hold the sensor over a container with the cathode pointing down.
Remove the fill plug.
Allow the electrolyte solution to drain out.
Wrap the plug with several turns of pipe tape and set aside.
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.
Hold the sensor at about a 45° angle with the cathode end pointing up.
Add electrolyte solution through the fill hole until the liquid overflows.
Tap the sensor near the threads to release trapped air bubbles.
Add more electrolyte solution if necessary.
Place the fill plug in the electrolyte port and begin screwing it in.
After several threads have engaged, rotate the sensor so that the cathode is
pointing up and continue tightening the fill plug.
Do not overtighten.
Place a new O-ring in the groove around the cathode post.
Cover the cathode with electrolyte solution; then place the membrane assembly
over the cathode.
Screw the membrane retainer in place.
Hold the sensor with the cathode end pointing down.
Give the sensor several sharp shakes to dislodge air bubbles trapped behind the
cathode.
The sensor may require several hours operating at the polarizing voltage to
equilibrate after the electolyte solution has been replaced.
Spare Parts
Description
Electrolyte fill plug with wooden osmotic pressure relief port
O-ring, Viton 2-014
Membrane retainer
Monochloramine membrane assembly: includes one membrane assembly and
one O-ring
Monochloramine membrane kit: includes three membrane assemblies and
three O-rings
Monochloramine sensor fill solution, 4 oz (120 mL)
Maintenance
59