Raven SCS 4600, Operator'S Manual

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APPENDIX 5
FLOW METER MAINTENANCE AND ADJUSTMENT
PROCEDURE
1) Remove Flow Meter from sprayer and flush with clean water to remove any chemicals.
NH
3
WARNING: Thoroughly bleed nurse tank hose and all other system lines prior to
disassembling the Flow Meter, fittings, and hoses.
2) Remove flange bolts or clamp from the Flow Meter.
3) Remove the turbine hub and turbine from inside Flow Meter.
4) Clean turbine and turbine hub of metal filings or any other foreign material, such as wettable
powders. Confirm that the turbine blades are not worn. Hold turbine and turbine hub in your hand
and spin turbine. The turbine should spin freely with very little drag inside the turbine hub.
5) If transducer assembly is replaced or if turbine stud is adjusted or replaced, verify the turbine fit
before reassembling. Hold turbine hub with turbine on transducer. Spin turbine by blowing on it.
Tighten turbine stud until turbine stalls. Loosen turbine stud 1/3 turn. The turbine should spin freely.
6) Re-assemble Flow Meter.
7) Using a low pressure (5 psi) [34.5 kPa] jet of air, verify the turbine spins freely. If there is drag, loosen
hex stud on the bottom of turbine hub 1/16 turn until the turbine spins freely.
8) If the turbine spins freely and cables have been checked per Appendix "PROCEDURE TO TEST
FLOW CABLES", but Flow Meter still is not totalizing properly, replace Flow Meter transducer.