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Oil Pressure Gauge: Description and Operation

DESCRIPTION
This oil pressure indicating system incorporates an instrument voltage regulator, electrical oil pressure gauge and a sending unit which are connected in series. The sending unit consists of a diaphragm, contact and a variable resistor.

OPERATION
As oil pressure increases or decreases, the diaphragm actuated the contact on the variable resistor, in turn controlling current flow through the gauge. When oil pressure is low, the resistance of the variable resistor is high, restricting current flow to the gauge, in turn indicating low oil pressure. As oil pressure increases, the resistance of the variable resistor is lowered, permitting an increased current flow to the gauge, resulting in an increased gauge reading.