Loading ...
Loading ...
Loading ...
VDL (E3.1) 10/2020 Page 87/196
9.3.2 Sweeping before starting up / restarting the chamber
Before turning on the VDL it is mandatory to sweep the area for electrical equipment, the preheating cham-
ber and controller housing with compressed air at maximum overpressure for a defined time.
Compressed air sweeping before start-up takes place in two steps. Be sure to follow the given
order.
Sweeping the electrical installation room, preheating chamber and controller housing (instrument
triangle)
• Turn the pressure regulator until the clamping ring touches the lower stop (turn clockwise). This gives
the maximum overpressure.
• Open the sweeping plug on the chamber rear next to the pressure regulator
• Check that compressed air flows out of the sweeping plug (caution, the outflowing air may be hot)
• Open the USB cover on the controller housing (instrument triangle)
• Check if compressed air is coming out of the USB cover (caution, the outflowing air may be hot)
• Sweep with maximum overpressure for at least the following duration
VDL 23: 20 minutes
VDL 56: 30 minutes
VDL 115: 40 minutes
• Then close the sweeping plug on the chamber rear.
• Also connect the USB cover on the controller housing (instrument triangle)
• Now the pressure regulator can be turned back (counter-clockwise rotation) until the clamping ring
touches the upper stop. (Only tighten to the stop by hand)
• Check that there is an overpressure of at least 25 Pa (recommendation: >40 Pa).
9.3.3 Sweeping during chamber operation
Sweeping the electrical installation room, the preheating chamber and controller housing must take place
with an overpressure of at least 25 Pa (recommendation: >40 Pa) during the entire operation of the vacuum
drying oven. This operating point is defined on the pressure regulator when the clamping ring touches the
upper stop. Also after termination or cancellation of the drying process continued sweeping for at least 10
minutes is recommended.
Figure 24: Pressure regulator with defined setting at the upper stop
Loading ...
Loading ...
Loading ...