Cole Parmer 05017-10, Руководство пользователя

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TCCB-Thermocouple Calibration
Before beginning the temperature calibration, place a NIST calibrated
thermometer in the center of the vacuum oven chamber and close the
door. Press the MENU key until the upper display shows TCCB, then
press the SET key. The unit enters the thermocouple calibration mode and
displays the first temperature set-point (flashing). Allow the unit ample
time to reach each set point. A 50°C calibration point will take
approximately 2 hours to stabilize. When the chamber temperature has
completely stabilized, record the temperature of the thermometer in the
chamber center. Using that value as the reference, use the UP/DOWN
keys to match the oven display temperature to the reference temperature.
Press the SET key. The controller will WAIT and SAMPLE values for the
low end calibration, then displays the second temperature set-point
(flashing). Use the UP/DOWN arrow keys to adjust the desired second
set-point. Press the SET key to enter the second set-point. Allow the unit
time to heat and stabilize at the second set-point. When the unit is stable,
record the temperature of the reference thermometer. Adjust the display to
match the reference thermometer using the UP/DOWN arrow keys. Press
the SET key. The controller will then SAMPLE this data. When the
controller is finished, the next menu will appear (VCMC).
VCMC-Vacuum Calibration
Before calibrating the vacuum readout system, it is necessary that the
barometric or atmospheric pressure be known. One way of doing this is to
contact the U.S. Weather Bureau in the installation area. The bureau will
provide the barometric pressure corrected to sea level, this pressure must
then be corrected to the altitude where the calibration will be performed.
This can be done by interpolating the data from Table 9. Once a pressure
for the calibration altitude is obtained, the value is subtracted from the sea
level value on Table 9 to obtain the correction factor. The correction
factor will then be subtracted from the value obtained from the bureau.
Obviously, the corrected value obtained will be only as accurate as the
accuracy to which the exact elevation is known.
Example: The barometric pressure corrected to sea level, as reported by the
U.S. Weather Bureau on June 13, 1983, was 30.19 In. of Hg, in
Pittsburgh, PA. The elevation at the calibration site, also in Pittsburgh, is
850 ft. above sea level. Interpolating the data from Table 9, the pressure at
850 ft. is 29.02 In. of Hg; subtracting this value from 29.92 (sea level
pressure) gives a correction factor of 0.9. The actual pressure at the
calibration site is: 30.19 - 0.9 = 29.29 In of Hg.
Vacuum Oven 6-13 Cole-Parmer
Section 6
Operation