Cole Parmer 05017-10, Руководство пользователя

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VCMC-Vacuum Calibration (continued)
Another method is to read the pressure directly from a temperature
compensated barometer that can be adjusted for altitude. This method will
give the pressure at the elevation of the calibration site without the need
for any additional calculations or corrections. Generally, the pressure value
measured should fall within the 29 to 30 inches-of-mercury range. In fact,
measurements outside this range should be suspect.
Slight variations will exist usually because of pressure variations due to
weather conditions. Therefore, the most accurate way to calibrate the
Model 282A vacuum readout system is to first obtain the atmospheric
pressure using one of the methods previously listed.
Note The procedure below for calibrating the vacuum display assumes the
vacuum pump is being controlled by the Auxiliary Contacts, Tabs 3 & 4.
The vacuum display can be calibrated with manual pump operation, as
well.
s
To calibrate the vacuum display, perform the following:
1. While in the VCMC calibration mode, open the vacuum (full-CCW)
valve to expose the chamber to atmospheric pressure.
2. Connect a suitable vacuum pump to the PURGE port along with a
vacuum gauge as shown in the illustration below.
3. Press the SET key to enable vacuum calibration. The upper display will
show PRSR with the AM LED flashing. The lower display will indicate
29.0 in Hg.
4. Use the UP/DOWN arrow keys to set the displayed pressure to match
the atmospheric pressure.
6-14 Vacuum Oven Cole-Parmer
Section 6
Operation
Vacuum Pump Hookup