HF scientific DRT-15CE Portable Turbidimeter - Manual (Page 14)

DRT-15CE (5/10) Page 6
Each kit contains:
-- Instruction manual
-- 1 liter of 4000 NTU Stock Suspension
-- 1 Gallon (3.79 liters) turbidity-free water
-- 4 Sample cuvettes (28 mm)
-- 4 Light Shield Caps
-- Graduated Pipettes 1 ea. in 1 ml, 10 ml, & 25 ml
-- 1 Calibration Standard
The following table gives the recommended dilutions of the stock suspension.
Be sure to adequately mix the stock suspension prior to removing a portion
for dilution.
PROCEDURE
NTU Value Pipette Amount Base
Formazin
Volumetric
Flask
10.0 NTU 10.0ml 2.5ml of 4000 NTU 1000ml
100.0 NTU 10.0ml 5.0ml of 4000 NTU 200ml
1000.0 NTU 25.0ml 25.0ml of 4000 NTU 100ml
NOTE: When the prepared samples start to flocculate, they are
unreliable and fresh ones must be made. This will occur
more rapidly for the lower value diluted suspen sions.
Prepare 40 NTU and lower standards daily.
7.2 ELECTRONIC CALIBRATION USING FACTORY
CERTIFIED PROCAL STANDARDS (CAT. NO. 39071)
The DRT Turbidimeters have been carefully calibrated at the factory.
However, should the Electronic P.C. Board, the Photo Detec tors, or the Light
Source be replaced recalibration may be easily accomplished at your facility.
To carry out a complete calibration the following ProCal Standard values are
required: