Partial-vacuum canisters

Vacuum is applied to the partial-vacuum canisters by the changeover valves and pressure converters. The partial-vacuum canister contain membranes that are moved by the partial vacuum. The linkage attached to the membranes is connected to the actuators in each case and operates these.

The partial-vacuum canisters must be checked for the following faults: 

• No transmission of force between membrane and linkage: 

  Pull the linkage out of the partial-vacuum canister slightly. If the linkage can be pulled out without resistance, the partial- vacuum canister is defective.

• Membrane is leaking 

  Use a vacuum pump to apply 500 mbar of partial vacuum to a partial-vacuum canister. If the partial-vacuum canister does not maintain the partial vacuum, the partial-vacuum canister is defective.