Shellab SCO26H-2 - Manual (Page 10)

OPERATION
It is recommended that your unit be allowed to reach operating temperature before engaging the humidifying
system. This requires setting the RH set point to the farthest counterclockwise position until the unit is at
operating temperature. See Section 6.6 for changing the RH set point.
7.1 Turn the power switch to the I/ON position. Turn the Over Temp Limit thermostat to its maximum
position, clockwise and place the shelves in the chamber.
7.2 Place a reference thermometer in the chamber where it can be easily viewed, and so that it is not
touching any shelves or chamber walls. Taping the thermometer to a petri dish is a method that
works well.
7.3 Set Main Temperature Control: To enter the set point on the control, push and release either the
UP or DOWN arrow pad one time and the digital display will start to blink from bright to dim. While
blinking, the display is showing the set point, which can be changed to the desired temperature by
pushing the UP or DOWN arrow pads. If the arrow pads are not pushed within five (5) seconds, the
display will stop blinking and will read the temperature in the chamber. Allow at least twenty- four
(24) hours for the temperature to stabilize. It is recommended that set point adjustments are made
again after the calibration procedure is completed.
7.4 Calibrating Temperature Control: Compare the reading on the reference thermometer with the
digital display. If there is an unacceptable difference, put the display into calibrate mode by pressing
both the UP and DOWN arrow pads at the same time and holding them in until the two outside
decimal points start to flash (approximately 5 seconds). When the decimal points are flashing, the
display can be calibrated to match the reference thermometer by pressing the UP or DOWN arrow
pad until the display reads the correct reference value. Allow the unit to stabilize again overnight
before re-calibrating.
7.5 Set the Over Temp Limit Thermostat: After the Main Temperature Control is set and calibrated
the Over Temp Limit needs to be set. First turn the control knob counterclockwise just until the Safety
Indicator light comes on. Then very slowly turn the knob clockwise just until the Over Temp Indicator
light goes off. The Limit thermostat should now be set approximately 1.0 degree above the Main
Temperature Control set point.
7.6 Set Humidity Control: First, place a reference hygrometer in the chamber where it can be easily
viewed. To adjust the internal humidity level turn the humidity control knob clockwise from LOW to
HIGH until the desired setpoint is reached. The low value on the scale is approximately 40% RH.
The high value on the scale is dependent on the internal temperature setpoint. See Section 11 for a
graph of the achievable humidity values with reference to internal temperature setpoint and the
dewpoint. Allow at least twenty four (24) hours for the unit to stabilize.
Section
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