Eppendorf TCA-3 Temperature Monitoring System - Manual (Page 44)

Calibration instructions
TCA-3 Temperature Monitoring System
English (EN)
44
If the other sensors need calibrating on the TCA-3 monitoring system they are done in the same way.
6.3 Two point calibration
If the temperature being measured is across a range (for example between +25 °C and -25 °C) then a two
point calibration should be used.
6.3.0.1 Requirements
• TCA-3 monitoring system
• Temperature probe connected to the TCA-3 monitoring system
• Access to Eppendorf software including login and password
• Calibrate temperature source/thermometer
6.3.0.2 Calibration instructions
In the Sensor Preferences make sure the Calibration Offset is set to 0.0 and the Calibration Gain is set to
1.0.
This is done by clicking on the Preferences Icon for that probe. In the Sensor Preferences window click
on the Advanced Tab, and then enter the two values.
• Set the temperature source to the required temperature (this will need to be the temperature that is
being permanently measured) if it is not calibrated verify using a thermometer.
• Place the temperature probe installed in the TCA-3 monitoring system into the temperature source and
allow to settle down, this may take a while.
• Take a note of the temperature of the temperature/thermometer and the temperature probe connected
to the TCA-3 monitoring system through the Eppendorf web service. Note: This needs to be done at the
two calibration points that are required.
• When there are two points then the gain needs to be worked out first which can be found from (higher
calibration point – lower calibration point) / (higher TCA-3 monitoring system value – lower TCA-3
monitoring system value).
For example, if the calibration points are 25.00 °C and 73.00 °C, and the TCA-3 monitoring system reads
26.25 °C and 76.25 °C, then the gain is (73.00 – 25.00) / (76.25 – 26.25) = 48.00 / 50.00 = 0.96.
• Next the offset needs to be calculated by multiplying either (or both) of the TCA-3 monitoring system
values by the gain and then subtracting that from the calibration value as before.