ThermoForma 3033 Operating And Maintenance Manual Download

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b. RH Calibration

Equipment required: Humidity sensing instrument of known
accuracy.

1. Place the reference humidity instrument in the center of

the chamber.

2. Allow the incubator to run at the desired humidity level

for at least an hour after it has stabilized.

3. Record the humidity level shown by the reference

instrument and the humidity level displayed on the RH
Control module.

4. Turn the Program/Run key switch to Program.
5. Turn the incubator off.
6. Press and hold the inverted Y button on the RH module

and turn the power switch on. Press the inverted Y key
until the beeping stops.

The incubator RH is ready for calibration when the tem-

perature display and CO

displays read 00.0. If the word SET

appears in the LCD window, press the inverted y button to
remove it.

When in the RH Calibration mode, the display shows the

temperature (°C) of the water in the humidity reservoir, not the
RH concentration.

7a. Using the arrow touch buttons, adjust the display

upward or downward. If the RH reading was lower than
the reference instrument, increase the display by 0.2°C
for each percent that the (RH) incubator reading was
low.

Example:

If the RH display reads 85% and the reference

instrument reads 87%, increase the display reading by 0.4°C.

7b. If the RH Control reading was higher than the reference

instrument, decrease the display by 0.2°C for each per-
cent that the (RH) incubator reading was high.

Example:

If the RH display reads 87% and the reference

instrument reads 85%, decrease display by 0.4°C.

8. Turn the incubator off, then back on without pressing

any buttons.

9. Return the Program/Run key switch to Run.

c. Temperature Calibration

Any change in temperature calibration will
require adjustments to the temperature
alarm/monitor, RH control and temperature con-
trol. Failure to make these adjustments will result
in incorrect humidity control, poor temperature
uniformity, or both.

Equipment Required: a thermometer of known accuracy.

1. Place the reference thermometer in the center of the

chamber.

2. Close both incubator doors and allow the incubator tem-

perature to stabilize for about one hour.

3. Record the temperature indicated on the thermometer

and the temperature readout on the Temperature
Alarm/Monitor Module.

4. Carefully swing open the control panel and identify the

Temperature Alarm module.

5. Locate the adjustment

potentiometer labeled
Zero. Refer to the illustra-
tion at the right.

6. Using the adjustment

screwdriver, turn the Zero
pot until the displayed
temperature agrees with
the reference thermometer.

7. Close the control panel,

taking care not to pinch
the ribbon wires inside the
compartment.

8. Turn the Program/Run key switch to Program.
9. Turn the incubator off.
10. Press and hold the inverted Y touch button on the RH

module while turning the power switch on. Press the
inverted Y button until the beeping stops. When the unit
is ready for calibration, the temperature display and the
CO

display will read 00.0.

Note:

If the word SET appears in the lcd window, momentarily

press the inverted Y button to remove it.

11. Using the up or down arrow buttons, change the display

by an amount equal to the amount the Temperature
Alarm/Monitor display was changed.

Example:

If the reference instrument reads 37.5 and the

Temperature Alarm/Monitor reads 37.0, the display would have
been increased 0.5. Therefore, the RH Control display must
also be increased 0.5.

12. Turn the incubator off.
13. Press and hold the inverted Y touch button on the

Temperature Module while turning the incubator on.

Note: