Quincy Compressor QSI Series, Instruction Manual

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Section II - Description
10
Quincy Compressor-QSI
®
Electrical System
A diagram of the electrical system is shown in the parts
manual sent with the compressor. A wiring diagram
is also included in the control panel on all Quincy QSI
compressors.
NOTICE!
Due to continuing product improvements and
updates, it is suggested that the wiring diagram
included in the control panel be used when servic-
ing the electrical control.
Standard drive motors are open drip proof 1800 RPM
with a maximum ambient temperature rating of 104°F.
They are not suitable for salt laden, corrosive, dirty, wet
or explosive environments.
The QSI series compressors utilize 460V incoming power
through an across-the-line magnetic starter. A trans -
former in the control panel reduces this voltage to 120
VAC for the various controls on the unit. These controls
include the selector switch, pressure switch, timer, high
air temperature safety switches, solenoid and the vari-
ous indicator lights. Other incoming line voltages are
available as options. The compressor is provided with a
NEMA 1 enclosure. Optional panels include NEMA 4.
Air-cooled models utilize a second magnetic starter for
protection of the fluid cooler fan motor. This starter is
connected to the compressor starter through an interlock
which insures the fan motor is operating with the com-
pressor motor. If the fan motor starter trips out for any
reason, the compressor unit will shut down.
DANGER!
High voltage could cause death or serious injury.
Disconnect all power supplies before opening the
electrical enclosure or servicing.
Safety Sensors
Two high air temperature (HAT) sensors are standard on
the QSI units. These sensors protect the unit by sensing
unusually high temperatures and shutting the unit down.
One is located in the discharge line from the compressor
to the air/ fluid reservoir. The second is located in the top
of the air/fluid reservoir. These sensors are set to trip at
approximately 225°F. The sensors are nonadjustable.
WARNING!
Never remove, bypass or tamper with the safety
HAT switch. Failure to provide this safety feature
could cause death or serious injury and property
damage. If the compressor is shutting down due
to high discharge temperature, contact a qualified
service technician immediately.