Gardner Denver AirSmart EAU99T, Operating And Service Manual

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Overload protection is provided for each motor on full voltage and Wye Delta applications. The overloads
are adjustable and are factory set based on the motor nameplate amps and the instructions located inside
the control box door. Less starter applications utilize a control relay for control of a remote mounted
motor starter (not provided with compressor package). Wye-delta starters employ three contactors which
are controlled sequentially to provide low current starting. For wye-delta starters, the motor nameplate
amps must be first multiplied by 0.577 before using the heater table.
COMPRESSOR CAPACITY CONTROL - TURN VALVE UNITS ONLY
The capacity of the compressor is controlled by the action of the turn valve and the compressor inlet
valve.
The turn valve controls compressor delivery to match demands of 40% to 100% of the compressor’s
maximum capacity. The inlet valve throttles to control compressor delivery to match demands of 0% to
40% of the compressors maximum capacity.
Example with normal setting of 100 PSIG:
Compressor Delivery
Capacity
Inlet Valve Position Turn Valve Position Discharge Manifold
Pressure (psi)
Full Open Closed 100
70% Open 50% Open 100
40% Open Full Open 100
30% Closing Full Open 103
20% Closing Full Open 103
0% Closed Full Open 103