Spectrex PC-2300, Руководство по эксплуатации

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9
CALIBRATION 7
Setting the Threshold Dial – The threshold knob located on the front of the
instrument is set to 10 (“0” in the window and 10 marks on the circular dial) for a
1µm level.
Count Controls - Three calibration standards containing polystyrene spheres in
water. The specially formulated diluent is miscible and creates a very stable
suspension with slow settling characteristics. They provide a means of verifying
that the instrument is functioning properly.
○
Red capped bottle: This is the 4-5µm count control. It has a nominal
concentration of 1000 particles/mL with a threshold
setting corresponding to 1µm.
○
Green capped bottle: This is the 1-2µm count control. It has a
concentration of 300 - 500 particles/mL with a
threshold setting corresponding to 1 µm.
○ White capped bottle:
This is the “ultra clean” standard or blank. It gives
average counts < 50 particles/mL with a threshold
setting corresponding to 1 µm.
The average of ten counts for any calibration standard should be within ±15 % of
the number stated on the bottle. This indicates that the particle counter is
calibrated correctly.
Procedure:
1. Begin by choosing one of the three calibration standards. The Green
and Red calibration standards should be resuspended before use by
inverting and swirling gently 10 times. The White calibration standard
should never be shaken.
2. Place the bottle firmly on the “V” block. Allow 1 minute for the red
and green bottles to de-gas as bubbles may appear as statistical
artifacts. Do not sonicate. Make sure the threshold knob is set to 10
(“0” in the window and 10 marks on the circular dial).
3. Press the Count button and wait for the red indicator light to go out
(approximately 16 seconds). The number of particles/cc above the
size selected will show in the display window and should match the
number stated on the bottle to ±15%.
4. Repeat until all three calibration standards have been tested.