Hampshire Controls Corp.
Revision 1.2
Temperature Transmitter Operating Instruction
Page 17 of 21
©2014
Calibration Mode
Calibration Mode is entered by pressing-and-holding the MUTE/CAL button during the 10
second power-up delay. If the Temperature Transmitter is in its normal operating mode, you
must first tap the RESET button. The STATUS LED will illuminate red
. When the STATUS
LED illuminates, immediately press-and-hold the MUTE/CAL button until the STATUS LED
turns off. Release the MUTE/CAL button. The LCD will turn on and may display either the
current temperature or the current analog-to-digital converter (A/D) reading.
It is recommended to change the temperature display to °C in the Sensor Settings before
beginning any calibration.
One-Point Calibration (Offset)
If One-Point Calibration (1Pt) has been selected, the LCD will display the current probe
temperature. The temperature readout will update every half second. To change the calibration
of the sensor you can tap the DISP/PROG button to increase the sensor readout or the
MUTE/CAL button to decrease the sensor readout until it matches the reading of a calibrated
thermometer. Each button tap adjusts the calibration offset by 0.05°C. The decimal digit on the
LCD may flicker ±0.1°C, this is within the accuracy limits of the Temperature Transmitter.
Once you are satisfied with the temperature reading on the LDC, press-and-hold the DISP/PROG
button until you hear a beep. Release the DISP/PROG button and then tap the RESET button to
re-boot the sensor. The sensor will use the new calibration offset when it restarts.
For best results, the sensor probe and the calibrated thermometer probe should be in very close
proximity. Both probes should be immersed in, and acclimated to a liquid of uniform
temperature. The temperature of the calibration medium should be close to the expected nominal
probe temperature of the sensors intended application (i.e. room, refrigerator or freezer
monitoring).
If you find that the sensor reading is correct at the calibration temperature but incorrect at a
higher or lower temperature, the sensor will require a Two-Point Calibration (2Pt) using the
method described in the following section. If you do not have the equipment to perform the
Two-Point Calibration, contact Hampshire Controls Corp. to arrange for factory recalibration.
Performing the One-Point Calibration at two different temperatures does not constitute a Two-
Point Calibration. Only the most current One-Point Calibration value is stored.
