3
4 pH
CALIBRATION
This section is applicable for the following models:
•
Eutech Instruments: EC-PHFM1ST11 & EC-PHFM1ST21
•
Oakton Instruments: 35623-00, and -05 only
4.1 Important
Information
on pH Monitor Calibration
This monitor has 3 pH calibration points: 4, 7 and 10 with automatic buffer
recognition. For best accuracy, calibrate to all 3 pH points close to the temperature of
the solution you will be monitoring, starting with pH 7. We recommend that you
perform at least a 2-point calibration—at pH 7 first followed by pH 4 or pH 10
depending on the range of the operation. You can also perform a 1-point calibration,
but make sure that the buffer value is close to the sample value you are measuring.
Calibration should be performed regularly to ensure accuracy. Frequency of
calibration will vary and should be checked regularly until the required schedule has
been determined.
Be sure to remove the protective electrode storage bottle or rubber cap of the probe
before calibration or measurement. If the electrode has been stored dry, wet the
probe in tap water for 10 minutes before calibrating or taking readings to saturate the
pH electrode surface and minimize drift.
Do not reuse buffer solutions after calibration. Contaminants in the solution can affect
the calibration, and eventually the accuracy of the measurements.
.
NOTE: All new calibration data will over-ride existing calibration data.
