VD (E2.1) 10/2011 page 54/83
Checking the spatial temperature exactitude
• Fix at least 9 sensor probes on 3 racks with adhesive aluminum tape or thermal conductive paste to
ensure sufficient thermal conductivity
• The distance of the sensor probes to all inner chamber walls must be at least 10% of the
corresponding inner chamber dimension (see DIN 12880).
• Perform the measurement in a thermally stable condition with 3 expansion racks and empty oven.
• Response time: at least 12 hours.
Do NOT use the temperature probe of the reference measurement device without any contact
to the expansion rack, i.e., do NOT measure vacuum values!
In case the temperature probe is a thermo element, mount it so it is electrically insulated from
the rack.
If you note an excessive divergence between the controller and reference temperatures, please contact
BINDER Service to calibrate the temperature controller.
14. Commissioning the vacuum
With regard to operation, please observe the guideline BGI/GUV-I 850-0 on safe working in laboratories
(formerly BGR/GUV-R 120 or ZH 1/119 laboratory guidelines issued by the employers’ liability insurance
association) (for Germany).
Starting situation: The vacuum source is connected and ready for operation.
For the vacuum module with chemical membrane pump option, see chap. 16.3 and 16.4.
14.1 Evacuation
• VD 23: Close the air/gas valve (4).
• VD 53 and VD 115: Close the aeration valve (5) and the fine dosing valve for inert gas (6).
• Turn on the vacuum pump.
• Put the lever of the vacuum shut off valve (8) to
“ON” position (valve open).
• Monitor the internal pressure on the pressure
display (3). The analog manometer displays the
running evaporation respectively the end of the
drying procedure. The scale of the manometer (3)
refers to an ideal ambient pressure of 1013 mbar
/ 29.9 inHg. Tolerance: 50 mbar / 37.5 mm Hg
(Torr) / 1.48 inch Hg (2.5% of the final scale value
+ reading precision). The optional digital pressure
display (chap. 16.5) offers an absolute scale.
•
When the desired end vacuum is obtained, turn
the VDL vacuum shutoff valve (8) to the “OFF”
position (valve closed). The reached vacuum is
now maintained.
Figure 13: Manometer display
The permissible end vacuum is 10
-2
mbar / 0.0003 inHg.
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