CDi users are expected to download the latest help file from the info section of this site. The calibration process involves setting two points, minimum and maximum representing the input range of the variable.
Most inputs only generate numbers in the positive part of the range.
Required tools For temperature calibration you should have a thermometer. For pH, you will need two different buffer solutions, preferably pH 4 and pH 10. If pH 10 buffer is not available, use pH 7. Do this only for DO channels . Always wait for the reading to stabilize before before you accept the value indicated.