Techne DB-2TC - Manual (Page 31)

CALIBRATION
Remember that if you change the calibration from that set at the factory you may change the
calibration at all temperatures. You may get different calibration with different blocks.
Make sure that you have good thermal contact between the blocks and the heater plate in the Dri-
Block
® . In order to ensure that the calibration you are setting is correct, you will need to use an
independently calibrated probe or thermometer.
Measure the actual temperature of the particular block you want to use in the Dri-Block ® using the
calibrated probe or thermometer. If the calibration is not correct then you can follow this procedure.
Make sure that the block and the unit are below 35°C.
1 Set the temperature display to 0.0°C. This will ensure that the block is at ambient temperature for the
next procedure.
2 Hold down the Up and Down buttons and then press the set button at the same time for 5 seconds.
The display will change from the set temperature, 0.0, to the block temperature to indicate the start
of self-calibration.
3 After a period of 17 minutes for the DB-2D or 25.5 minutes for the DB-3D the display will change
from the block temperature (eg 40.0°C) to “EEEE”. Measure the actual temperature of the block using
the thermometer or probe. Press the ‘SET’ button and either the ‘UP’ or the ‘DOWN’ button to adjust
the display to the same temperature as the measured value.
4 Press the ’UP’ and ‘DOWN’ buttons together to confirm the value. The display will return to the block
temperature and the heater will come full on.
5 After a period of 29.75 minutes for the DB-2D or 34 minutes for the DB-3D the display will change
from the block temperature (eg 95.0°C for the DB-2D or 195°C for the DB-3D) to “EEEE”.
6 Measure the actual temperature of the block using the thermometer. Press the ‘SET’ button and either
the ‘UP’ or ‘DOWN’ button to adjust the display to the same temperature as the measured value.
7 Press the ‘UP’ and the ‘DOWN’ buttons together to confirm the value. The display will return to the
block temperature and the unit will control with the new calibration parameters.
8 Set the temperature to the particular temperature you require. Measure the temperature when the
block temperature has stabilised. Repeat the procedure as necessary; you may need to put in an off-
set.
CALIBRATION - TWIN CONTROL (DB-2TC)
These units are calibrated during manufacture using blocks designed for 16mm tubes. The different mass
of aluminium in blocks designed for other sizes or types of container can cause small discrepancies
between the displayed temperature and the actual temperature of the blocks.
If the block heater is to be used with other blocks and very accurate temperature setting is required then
the unit should be re-calibrated for the blocks to be used.
You will need an accurately calibrated thermometer for this procedure to be worthwhile. The
block heater can only be as accurate as the thermometer used to calibrate it.
Follow the procedure outlined on the next page.
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