Siemens interranger DPS300 Instructional Manual page 32

Operation
As the skimmer passes, it contacts the skimmer guard and pushes it up and over
the skimmer; effectively clearing the transducer out of harm's way. Once the
skimmer has passed, the guard is free to fall, re-immersing the transducer into the
clarifier water.
Note:
Before leaving, run the skimmer to insure that the skimmer guard is operating
properly.
InterRanger DPS300
skimmer direction
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