Gardner Denver ELECTRA-SAVER G2, Руководство по эксплуатации и обслуживанию

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13-21-611 Page 39
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Power Supply - This device changes the incoming AC supply voltage to 24 volts DC for use by all unit
control devices. For 575 volt AC units only, a control transformer is provided to supply 120 volts AC input
to the power supply. A secondary fuse is provided on the control transformer. Refer to adjacent labeling
for replacement information.
Fuse Blocks - Two Class CC fuse blocks provide line side protection for the power supply and control
transformer, as applicable.
Terminal Strip - This provides connections for all 24 volt DC controlled devices not directly connected to
the AirSmart G2 controller.
Fan Starter - The starter is used to provide control and overload protection for the cooling fan or the
ventilation fan of water
– cooled units with enclosure. The overload should be adjusted based on the motor
nameplate amps and the instructions located inside the cover of the electrical enclosure. Three fuses are
provided. Refer to adjacent labeling for replacement information.
Main Starter - This starter is used to provide control and overload protection for the main drive motor.
Wiring diagrams for typical Wye Delta applications are illustrated on pages 44 thru 54.
Overload protection is provided for each motor on 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. 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 Turn Valve
Discharge Manifold
Pressure
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