YSI 85 - Manual (Page 21)

YSI, Incorporated Model 85 17
SECTION 7 MAKING MEASUREMENTS
7.1 TURNING THE INSTRUMENT ON
Once the batteries are installed correctly, press the ON/OFF button. The instrument will activate all
segments of the display for a few seconds, which will be followed by a self-test procedure that will
last for several more seconds. During this power on self-test sequence, the instrument’s
microprocessor is verifying that the instrument is working properly. The Model 85 will display the
cell constant of the conductivity probe when the self-test is complete. If the instrument were to
detect an internal problem, the display would show a continuous error message. See the section
entitled Troubleshooting for a list of these error messages.
7.2 THE MEASUREMENT MODES OF THE MODEL 85
The Model 85 is designed to provide six distinct measurements:
¾ Dissolved Oxygen % -- A measurement of oxygen in percent of saturation.
¾ Dissolved Oxygen mg/L -- A measurement of oxygen in mg/L
¾ Conductivity -- A measurement of the conductive material in the liquid sample without regard
to temperature
¾ Specific Conductance -- Also known as temperature compensated conductivity which
automatically adjusts the reading to a calculated value which would have been read if the sample
had been at 25
o
C (or some other reference temperature which you choose). See Advanced
Setup.
¾ Temperature -- which is always displayed.
¾ Salinity -- A calculation done by the instrument electronics, based upon the conductivity and
temperature readings.
NOTE: When you turn the Model 85 off, it will “remember” which mode you used last and will
return to that mode the next time the instrument is turned on.
To choose one of the measurement modes above (temperature is always displayed) simply press and
release the MODE button. Carefully observe the small legends at the far right side of the LCD.
Dissolved Oxygen
in % with°C
Dissolved Oxygen
in mg/L with °C
Conductivity with
°C
Specific
Conductance
with °C
Salinity with °C