temperature and the displayed temperature. Range -5° to
5°C. See Calibration Procedure.
Pct Menu
- (Percent Cooling Menu) Used to select one of
three cooling modes:
100% Mode - Compressor runs continuously which pro-
vides high precision control (±.2°C Stability) over entire
temperature range. Requires manual defrosting.
50% Mode - Compressor runs approximately half the
time, which conserves power and also reduces frost
buildup inside chamber. This method decreases the fre-
quency of manual defrosting but provides less tempera-
ture stability (±1.5°C).
00% Mode - Compressor is completely off. This mode is
ideal for incubating samples at temperatures 10°C or
higher above ambient (35°C to 60°C). It provides the
greatest power savings yet still maintains the advertised
stability. Defrosting is not required.
Pro Menu
- Protection Menu - Used to select the
Protection mode of operation that determines when the
alarm is activated and if the control setpoint can be
changed. Range 0.0 to 0.2.
0.0 Mode - Normal mode that allows the user to change
setpoint. Alarm activates if chamber temperature (cham-
ber) and setpoint temperature (setpoint) are as follows:
Chamber < 15.0°C and chamber < (setpoint -3) or
Chamber > 40.0°C and chamber > (se3)
While ALARM is activated, the safety relay is opened
interrupting power to the heater, fan, convenience outlet
and compressor. When chamber temperature returns to
acceptable limits, the ALARM will automatically terminate
and power is reapplied. In order to allow changing of set-
point and eliminate nuisance alarms, an alarm by-pass
takes effect when the setpoint is changed or when power
is first applied. The alarm by-pass works as follows:
Present chamber temperature is stored as a nominal
alarm temperature (nominal). If chamber < setpoint then
alarm temperature (alarm) = nominal -3. If chamber >
setpoint then alarm = n3. If chamber should go
beyond alarm or < -13 or > 63 then the ALARM will acti-
vate. This alarm by-pass is active until chamber reaches
setpoint ±1°C.
11
O
PERATION
