35
New Brunswick Scientific Co., Inc.
User’s Guide
7.6 Temperature
Setpoint
Press the
SELECT KEY
until the function
°
C INDICATOR
illuminates. The temperature can
be set from 5
°
C above ambient temperature to 60
°
C (non-refrigerated units) or from 4
°
C
to 60
°
C (refrigerated units). Increasing or decreasing the setpoint is accomplished with
the
V
or
W
KEY
. Ambient temperature is measured one meter from the front of the unit.
During operation, if the temperature of the chamber is more than 1.0
°
C higher or lower
than the temperature setpoint, an alarm is triggered. This alarm consists of a flashing
°
C
INDICATOR
and audible beep. The alarm will automatically deactivate as the unit
achieves the set temperature.
If desired, the temperature control system may be shut off during set-up for special
investigations. Perform the following steps:
1. To deactivate the temperature control system, press and hold the
W
KEY
until the
setpoint is at 4.0
°
C.
2. Holding
the
W
KEY
, press the
START / STOP KEY
.
3. The temperature setpoint display shows
OFF
and the control system will be
deactivated.
To reactivate the temperature controller, press the
V
KEY
until the desired temperature
setpoint is displayed.
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 heat exchanger 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.
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 unit equilibrate at or near the desired temperature. Record the Indicated
Temperature.
2. Record the Actual Temperature.
3. Calculate the temperature correction value: Actual Temperature – Indicated
Temperature = Temperature Correction Value.
