Myron L D-6 User Manual

Page 37

• Conductivity

• TDS

Order model RPR. When ordering, be sure to include the model and serial

number of your instrument to ensure receipt of the proper type.

E. Cleaning Sensors

1. Conductivity/TDS/Resistivity

The conductivity cell cup should be kept as clean as possible. Flushing

with clean water following use will prevent buildup on electrodes. However,

if very dirty samples — particularly scaling types — are allowed to dry

in the cell cup, a film will form. This film reduces accuracy. Whenever a

Conductivity Cell Cleanliness Check (Cell Check, pg. 30) indicates that the

conductivity sensor requires cleaning (“CELL cLn”), use isopropyl alcohol

or a foaming non-abrasive household cleaner. Rinse out the cleaner, and

your Dialysate Meter is again ready for accurate measurements.

2. Checking pH/ORP Sensor Performance (D-6)

A Digital Dialysate Meter™ pH sensor measures the electrochemical

potential between a 3.5 molar KCl solution inside the sensor and the

solution being tested (outside of the sensor).

Over time, as the pH sensor operates, the KCl solution is gradually

depleted. The rate at which this depletion occurs is very slow but is

accelerated if the sensor is not cared for properly.
To check the age-related drift of your instrument’s pH sensor junction:

Remove the protective cap from the pH/ORP sensor by

grasping its sides and pulling up.

Rinse both the pH sensor well and the conductivity cell cup

with 7.0 pH buffer solution at least 3 times.

Fill both the pH/ORP sensor well and the conductivity cell cup

with 7.0 pH buffer solution.

Press

• Three icons will appear in the display: “CAL”, “7” and

“BUFFER”.

DO NOT adjust the reading by pressing

Assuming the pH buffer is good, this value represents the offset of the

sensor.

• If the pH reading is above 8.0 pH or below 6.0 pH with 7.0 pH

buffer solution, both the “7” and “BUFFER” icons will flash.

• This indicates that the pH/ORP sensor needs to be

replaced.