YSI Level Scout - Manual (Page 18)

The Temperature measurement is based on the temperature of the pressure sensor. This is the temperature that is used for the
pressure calculation and thermal correction algorithms. This measurement is useful for understanding the temperatures the
pressure transducer is exposed to. Accuracy of this measurement is ± 1.0 ° C.
PCB-Temp is a high-accuracy temperature measurement that is available on the high memory Level Scout only (model VS4, VT4,
AS4 and AT4). The sensor for this measurement is located on the Level Scout’s circuit board, near the pressure sensor. Accuracy of
this measurement is ± 0.2° C.
The Supply Volts measurement provides an indication of the Level Scout’s internal battery voltage level. When using alkaline
batteries, the battery voltage will decay linearly with battery use. Note that not all battery technologies behave in this linear decay
manner. The Level Scout can operate from battery power as long as the reported battery voltages remain above 1.5 volts. Applying
external power to the Level Scout will result in a slight increase in the reported internal battery voltage of approximately 0.2 volts.
The Scan tab (figure 3.13) is used to display or configure the sampling method used for the selected test profile. Select one of the
four possible sampling methods (described below) from the Method pull down list.
Figure 3.13
„ Linear - Data is sampled at a constant, linear defined rate. The period between scans needs to be specified in
Days:Hours:Minutes:Seconds.
„ Linear-Average - Data is sampled at a specified period but logged at a slower rate. Each logged linear data sample
is the averaged value of the specified consecutive samples (2-250) that were acquired at the defined sampling rate.
Figure 3.14 shows a test where the instrument will take a sample once per minute and log the average of 10
samples. In this example, an averaged reading would be logged once every 10 minutes.
Figure 3.14
„ Logarithmic - The rate of data sampling and logging initiates at the fastest possible rate of the Level Scout. The
sample period then exponentially increases until the final maximum period is reached. The maximum period value
is user specified. Data then continues to be sampled and logged at this maximum period for the remainder of the
test profile. The initial scanning rate will be between 3 Hz and 10 Hz depending on the measurements and
averaging specified in the Level Scout. This sampling method is useful for situations where data is required at a
high sample rate initially but at slower rates as time elapses.
Figure 3.15
16 Level Scout YSI Incorporated