Owner's manual

32
5. Maintenance
5-1. Daily check
5-1-1. Cleaning the measuring cell
When the repeatability of measurements has degraded or measuring time is prolonged, the measuring
cell is considered to be contaminated. Also, when the cell is apparently contaminated with a sample of
such nature, the measuring cell must be cleaned with an appropriate solvent like household chlorine
bleach, acid or alkali. When particular samples containing fatty acids or protein (such as biodiesel) are
measured, the cell must be cleaned once a week as described below.
The following example describes how to rinse out fats and oils with Sodium hydroxide:
1) For units with the optional peristaltic pump installed
a. Insert the sampling tube into 0.1∼0.5mol/L Sodium hydroxide and press [PUMP] key to inject.
b. When the cell becomes filled with Sodium hydroxide, press [PUMP] key to stop filling.
c. Leave the sodium hydroxide in the cell for about 15 minutes.
d. Drain out Sodium hydroxide solution with [PUMP] key.
2) For units without the pump
a. Inject 0.1∼0.5mol/L Sodium hydroxide using a suitable 2-5 mL syringe.
b. Leave the sodium hydroxide in the cell for about 15 minutes.
c. Push out the sodium hydroxide from the cell using an empty syringe filled with air.
3) Clean the measuring cell with pure water according to the Step “3-4”.
Warning!
The alkali may etch the glass of the measuring cell. Avoid rinsing the
cell with strong alkali for hours. Always rinse the cell with plenty of pure
water after cleaning the cell with alkali cleaners.
CANNON
®
D155 Density Meter Instruction & Operation Manual
Version 1.1b – August 2014; CANNON® Instrument Company
2139 High Tech Road • State College, PA • 16803 • USA