Calibration readings are recorded in the instrument log book and on field forms at the time the instrument is calibrated. Remember, the temperature sensor on the conductivity sensor must be calibrated and District certified within the past 4 months. Calibration and operating procedures differ, depending on instrument and sensor type. Check the manufacturer's instructions.
Some analog instruments require an initial mechanical zero adjustment of the indicator needle.
When using a dip-type cell, do not let the cell rest on the bottom or sides of the measuring container. Conductivity systems normally are calibrated with at least two standards. Calibrate sensors against a standard that approximates sample conductivity and use the second standard as a calibration check. Inspect the instrument and the conductivity sensor for damage. Check the battery voltage.