摘要 |
A method and apparatus for reducing the pressure in an enclosure are provided. The method includes at least one primary pump on the outlet side and one secondary pump on the inlet side connected in series in the flow path of the pumped gases and driven in the same rotation direction by a first electric motor and a second electric motor, respectively, controlled by an electronic control module for modifying the speeds of the two electric motors independently, and includes at least one step, during reducing the pressure in the enclosure, of progressively increasing the rotation speed of the secondary pump in accordance with a rotation speed variation law of the secondary pump and at the same time progressively reducing the rotation speed of the primary pump in accordance with a rotation speed variation law of the primary pump.
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