USE OF FILTER-DRIER
Clean and dry systems are essential for long compressor and motor life, and satisfactory operation. This cannot be
over-emphasized.
Liquid line refrigerant filter driers maintain low moisture content, and in the event of a motor burnout, prevent
contamination of the evaporator and other parts of the refrigeration system.
Liquid line moisture indicators are recommended in all systems which use semi-hermetic compressors because they
provide a continuous check on the system's moisture content. Excessive moisture in combination with a high
operating temperature can lead to motor winding breakdown and burnout.
When moisture is indicated, prompt corrective action, such as changing the filter-drier core or dehydrating the
system, can prevent serious compressor damage.
Suction line filter driers are recommended for all systems because they assure adequate filtration Bust ahead of the
compressor. This is especially important on refrigeration systems where long suction lines are common and where
these filter driers would collect any dirt or other contaminants left in the piping during installation.
COMPRESSOR NAMEPLATE DATA
The compressor nameplate specifies voltage, phase, frequency, and lock rotor current.
The rated load current shown is the ,-mum must trip current that the motor draws when tripping the overload relays,
divided by 1.25.
The allowable variation in voltage at the motor terminals is within 10 percent of the rated nameplate voltage. A 460
volt motor can, therefore, operate satisfactorily between 414 and 506 volts at the motor terminals.
MOTOR PROTECTION
This compressor is provided with overcurrent and overtemperature protection which complies with UL and NEC
definitions of inherent motor protection. Full protection is provided for lock rotor, running overcurrent, primary and
secondary single phasing, and loss of refrigerant conditions.
1.
PRIMARY MOTOR OVERCURRENT PROTECTION is provided by two (2) Texas Instruments' supplementary
overloads. These are pilot duty, automatic reset, current sensitive devices mounted in the compressor
terminal box. Load terminals of the overloads are 1/4 inch quick connect for ratings of 30 amps and below,
and #10 screw terminals for ratings over 30 amps. Control circuit terminals of the overloads are 1/4 inch
quick connects.
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