Sensor drift compensation, Compensation procedure – YSI PC6000 User Manual

Page 34

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SECTION 8

SENSOR DRIFT APPLICATION NOTE

SENSOR DRIFT COMPENSATION

The following application note is designed to facilitate the use of the sensor drift software included
in the PC6000 package by providing the user with a specific example.

After laboratory calibration, a user deployed their sonde in a readily accessible stream on 10/14/92
with the instrument set to capture data to memory at 15-minute intervals. The study was named
SRUN7. The instrument was left in place for approximately 2 weeks and during this time period,
the user visited the site 3 times, took a water sample in a sealed bottle, and, on returning to the
laboratory, measured the dissolved oxygen and pH with recently calibrated instruments. The user
also collected a water sample when the instrument was retrieved (10/26/92) and measured dissolved
oxygen and pH in the laboratory. The following records were kept.

Laboratory Measurements

Date

Time

DO (mg/L)

pH

10/17/92

8:00

5.40

7.62

10/29/92

8:00

7.50

7.63

10/23/92

10:00

7.30

7.58

10/26/92

8:15

6.32

7.60

The user now has everything required to compensate the DO and pH readings for field drift:

"

The data file captured by the computer or data collection platform.

"

The correct DO and pH readings at various times during the study based on grab samples of
water which were analyzed with recently calibrated laboratory instruments.

"

PC6000 software for retrieval and manipulation of the data from the sonde memory.

COMPENSATION PROCEDURE

1-

For this example, make certain that the data file is present in a subdirectory of the hard
drive (C:\PC6000).

2-

"Exit" from PC6000 software using the top menu bar. The "C:\PC6000" prompt
should be displayed.

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