b. Setting the Overtemp Setpoint
The independent overtemp system is designed as a
safety to protect the incubator only. It is not
intended to protect or limit the maximum tempera-
ture of the cell cultures or customer’s equipment
inside the incubator if an overtemp condition
occurs.
All Model 3950 Series incubators are equipped with a sec-
ondary temperature monitoring system to monitor the air tem-
perature inside the cabinet. This system is designed as a safety
device to turn off all heaters in the event of a temperature con-
trol failure. The temperature control point in the incubator will
be approximately ±1°C of the overtemp setpoint.
The overtemp setpoint is set by the factory (default) at
40°C. However, the overtemp can be reset over a range from
0.5°C above the operating temperature setpoint to 65°C.
If the incubator’s operating temperature setpoint is set
above the overtemp setpoint, the overtemp setpoint will auto-
matically update to 1°C above the temperature setpoint. It is
recommended that the overtemp setpoint be maintained at 1°C
over the operating temperature setpoint.
To set the Overtemp setpoint:
1. Press the Mode key until the Set indicator lights.
2. Press the right arrow until Otemp XX.X is displayed in
the message center.
3. Press the up or down arrow until the desired Otemp set-
point is displayed.
4. Press Enter to save the setting.
5. Press the Mode key until the Run indicator lights, or
press the right or left arrow to go to the next or previous
parameter.
c. Setting the CO
2
Setpoint
All CO
2
cells are calibrated at the factory at 37°C,
medium humidity and 10% CO
2
. Therefore, if a temperature
setpoint of 37°C has been entered, the humidity reservoir has
been filled and the CO
2
control is set to run between 0-10%, the
CO
2
setpoint may be entered immediately. Otherwise, it is
important to allow the unit 12 hours to stabilize at the tempera-
ture setpoint before entering the CO
2
setpoint.
All models of the incubator have a CO
2
setpoint range of
0.0% to 20.0%. The incubator is shipped from the factory with
a CO
2
setpoint of 0.0%. At this setting, all CO
2
control and
alarms are turned off.
To change the CO
2
setpoint:
1. Press the Mode key until the Set indicator lights.
2. Press the right arrow until “CO2 XX.X” is displayed in
the message center.
3. Press the up/down arrow until the desired CO
2
setpoint
is displayed.
4. Press Enter to save the setpoint.
5. Press the Mode key until the Run indicator lights to go
to Run mode, or press the right/left arrow keys to go to
next/previous parameter.
Model 3950/3951 ____________________________________________________________________Installation and Start-Up
1 - 6
