YSI 550 DO, Руководство по эксплуатации

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YSI Incorporated YSI 550 DO Handheld Instrument 13
TO CALIBRATE IN MG/L:
To switch between mg/L and percent saturation to be displayed as the oxygen readings units, press
the Mode key. Either a “mg/L” or “%” will be displayed on the right side of the screen.
4. Make sure that the DO reading (large display) is stable, then press the ENTER button. The
YSI 550 DO instrument should now display CAL in the lower left of the display, the
calibration value should be displayed in the lower right of the display and the current DO
reading (before calibration) should be on the main display.
5. Make sure that the DO reading (large display) is stable, then press the ENTER button. The
LCD will prompt you to enter the approximate salinity of the water you are about to analyze.
You can enter any number from 0 to 40 parts per thousand (PPT) of salinity. Use the arrow
keys to increase or decrease the salinity setting. When the correct salinity appears on the LCD
(zero for fresh water), press the ENTER key. The instrument will return to normal operation.
Once the calibration process is complete, the only keys that will remain operational are the MODE
key, the LIGHT key and the ON/OFF key. You can move back and forth from reading dissolved
oxygen in the mg/L mode or the % air saturation mode by pressing the MODE key. If you are
working in a dark area and have difficulty reading the LCD, press the LIGHT key to activate the
back-light of the YSI 550. The ON/OFF key turns the instrument on or off.
For best results:
!
Each time the YSI 550 DO Instrument is turned off, re-calibrate before taking measurements.
!
Calibrate at a temperature within
±
10°C of the sample temperature.
TO CALIBRATE IN % SATURATION:
To switch between mg/L and percent saturation to be displayed as the oxygen readings units, press
the Mode key. Either a “mg/L” or “%” will be displayed on the right side of the screen.
4. IF you are calibrating in % saturation mode, the LCD will prompt you to enter the local
altitude in hundreds of feet. Use the arrow keys to increase or decrease the altitude.
EXAMPLE: Entering the number 12 here indicates 1200 feet.
6. When the proper altitude appears on the LCD, press the ENTER key. The YSI 550 DO
Instrument should now display CAL in the lower left of the display, the calibration value
should be displayed in the lower right of the display and the current DO reading (before
calibration) should be on the main display.
7. Make sure that the DO reading (large display) is stable, then press the ENTER button. The
LCD will prompt you to enter the approximate salinity of the water you are about to analyze.
You can enter any number from 0 to 40 parts per thousand (PPT) of salinity. Use the arrow