Description The present set-up is designed to study the Double Stage Air compressor. The set-up consists of a double stage reciprocating type air compressor. It is driven by a motor through a belt and pulley system. The drive motor is swinging field type and supplied with dial type spring balance which permits direct torque measurement. This arrangement facilitates the end user to calculate the power transmitted by the motor to the compressor, accurately. To calculate input power to the motor, an energy meter is provided and, in this way, by knowing the input and output, efficiency of the compressor is calculated easily. The outlet of the air compressor is connected to air reservoir and suction is connected to another air manifold tank. The compressor draws air from this manifold tank which is provided with bellow at one side. This tank also has an orifice with manometer to observe and calculate the air flow rate. The compressed air from the outlet side of the compressor is stored in provided reservoir. The reservoir is equipped with Pressure Gauge, Control Valve, Safety Valve, Drain etc. An water cooled intercooler for air, in between both head, is provided to cool the hot and compressed air before entering the second stage. Temperature of inlet air, after single compression, inlet and outlet of second compression and pressure in reservoir and at intermediate stage can be measured by Temp. Sensorsand pressure gauges.