ATI
Q45P pH System
Part 7
–Troubleshooting
42
O&M Manual
Rev-B (7/15)
7.2
Replacing the Saltbridge and Reference Buffer Solution
1. Hold the sensor with the process electrode pointing up. Place a cloth or towel
around the saltbridge. Turn the saltbridge counterclockwise (by hand) to
loosen and remove the saltbridge. Do NOT use pliers.
2. Pour out the old reference buffer by inverting the sensor (process electrode
pointing down). If the reference buffer does not run out, gently shake or tap
the sensor.
3. Rinse the reference chamber of the sensor with de-ionized water. Fill the
reference chamber of the sensor with fresh Reference Cell Buffer. The
chamber holds 6 to 7 mL of solution. MAKE SURE that 6 to7 mL is used
when refilling. The chamber should be FULL.
4. Inspect the new saltbridge to verify that there are 2 o-rings inside the
threaded section of the saltbridge
5. Place the new saltbridge over the ground assembly of the sensor. Place a
cloth or towel around the saltbridge and hand-tighten the saltbridge by turning
it clockwise.
NOTE:
Every ATI Q25P Sensor includes a spare bottle of Reference
Buffer Solution, 7.0 pH. This is NOT typical pH 7 buffer, it is a special
“high-capacity” buffer developed to ensure the highest possible stability
of the reference portion of the pH measurement. No substitutions should
be made.
Figure 10 - Replacing the Saltbridge and Reference Buffer
