Eppendorf Innova 43R Incubator Shakers - Manual (Page 47)

47
New Brunswick Operating manual
7.7 Temperature Offset Calibration
The temperature probe and the temperature controller are calibrated together at the
factory. The temperature probe measures the temperature of the air at the probe’s
location, near the return vent. The controller uses the probe input to adjust air
temperature, up or down, to match the temperature setpoint.
Depending on various conditions within the chamber, such as flask placement and size,
the heat produced by growing organisms, heat losses due to liquid evaporation from
flasks, etc., the display temperature may differ from temperatures within the flasks
themselves. You can calculate the correction value for this offset and program the shaker
to display a corrected temperature.
7.7.1 Calculating the Offset Value
If you wish to have the temperature display (“Indicated Temperature”) match the
temperature at a given point, or match the average of a series of points within the
chamber (“Actual Temperature”), proceed as follows:
1. Let the shaker equilibrate at or near the desired temperature, then record the
Indicated Temperature.
2. Now record the Actual Temperature.
3. Calculate the temperature correction value using this formula:
Actual Temperature – Indicated Temperature = Temperature Offset Value.
4. To set the Temperature Calibration Offset, follow the procedure outlined in
Section 7.7.2 below.
7.7.2 Setting the Offset
To set the temperature calibration Offset :
1. Use the Control Knob to enter the
CAL screen (see Figure 20, repeated
below).
2. Turn the Control Knob to highlight the current setting ( 0.0 in the sample
screen above), then click the Knob in. The current setting will flash.
3. Turn the Knob (left for negative settings or right for positive settings) to
display the desired setting. As you turn the Knob, each click represents one
tenth of a degree Celsius (0.1ºC).
4. When you reach the desired setting, click the Control Knob in to save the new
value.