Glossary

CFM: Cubic feet per minute

SCFM: Standard cubic feet per minute; a unit of measure for air delivery.

PSlG: Pounds per square inch gauge; a unit of measure for pressure.

ASME: American Society of Mechanical Engineers.

California Code: Unit may comply with California Code 462 (I) (2)/(M) (2).

Cut-In Pressure: The air compressor will automatically

start to refill the tank when the pressure drops below the prescribed minimum.

Cut-Out Pressure: The point at which the motor stops when the tank has reached maximum air pressure.

Code Certification: Products that bear one or more of

the following marks: UL, CUL, ETL, CETL, have been evaluated by OSHA-certified independent safety laboratories and meet the applicable Underwriters Laboratories Standards for Safety.

Duty Cycle

This is a 50% duty cycle air compressor. Do not run the air compressor more than 30 minutes of one hour. Doing so could damage the air compressor.

Parts & Features

See figures below for reference.

Drain Valve: Used to drain condensation from the air tank. Located at bottom of tank.

Motor Thermal Overload: The motor has an automatic thermal overload protector. If the motor overheats, this protector will shut off the motor. The motor must be allowed 30 minutes to cool before restarting.

Quick Connect: Offers a quick release feature for attaching and removing the air hose.

Pressure Switch: This controls the power to the motor and also the cut-in/cut-out pressure settings. This switch serves as the Auto-On/Off positions for the unit.

Air Intake Filter: Provides clean air to the pump and

must always be kept free of debris. Check on a daily basis

Pressure Relief Valve; The pressure relief valve located on the side of the pressure switch, is designed to automatically release compressed air when the air compressor reaches cut-out pressure. The released air should only escape momentarily and the valve should then close.

Tank Safety Valve: Used to allow excess tank pressure to escape into the atmosphere. This valve should only open when the tank pressure is above the maximum rated pressure.

Outlet Pressure Gauge: Indicates the outgoing air pressure to the tool and is controlled by the regulator.

Tank Pressure Gauge: Indicates the reserve air pressure in the tank.

Air Compressor Pump: Oil lubricated direct driven pump that compresses air which is distributed to the tank (not shown).

Check Valve: When the pump is not in operation the valve closes to retain air pressure inside the tank. An internal component.

Pressure Relief

Tube

Switch---__

lii-_ _ Regulator

Pressure_

Regulator; The air pressure coming from the air tank is controlled by the regulator. To increase the pressure turn

the knob clockwise and to decrease the pressure turn the knob counterclockwise.

Oil Fill Cap

Oil Sight Glass

Outlet Tube

_

_

_Quick

ConneCtsocket

Valve

Tank Gauge

Regulator Gauge

Check Valve

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Craftsman 921.1521 owner manual Duty Cycle, Glossary
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921.1521 specifications

The Craftsman 921.1521 is a powerful and versatile tool that has garnered attention among DIY enthusiasts and professionals alike. This air compressor is designed to tackle a variety of tasks, making it an essential addition to any workshop or garage. With its robust features and advanced technologies, the 921.1521 stands out in its category.

One of the key features of the Craftsman 921.1521 is its impressive power output. This air compressor is equipped with a 1.5-horsepower motor, providing a substantial amount of air pressure for a wide range of applications. It has a maximum pressure of 150 PSI, which allows it to handle demanding tasks such as powering nail guns, spray painting, and inflating tires with ease.

Additionally, the 921.1521 is designed with a 6-gallon tank, which ensures a steady air supply for longer periods of use. This feature minimizes downtime, allowing users to complete their projects more efficiently. The tank is also constructed from high-quality materials, ensuring durability and longevity over time.

Portability is another significant aspect of the Craftsman 921.1521. It features a lightweight design coupled with a convenient handle, making it easy to transport from one job site to another. The compressor also comes equipped with rubber feet that provide stability during operation, ensuring safety and reducing vibrations.

The Craftsman 921.1521 incorporates user-friendly technologies, such as an automatic shut-off feature that helps prevent over-pressurization. This not only protects the compressor but also enhances user safety. Furthermore, maintenance is straightforward, with easy access to all essential components for routine checks and upkeep.

Another notable characteristic of the 921.1521 is its noise reduction capabilities. With noise levels significantly lower than many competitors, it is suitable for use in residential areas without disturbing neighbors. This feature makes it ideal for home improvement projects and other tasks where noise may be a concern.

In conclusion, the Craftsman 921.1521 air compressor is a powerful, portable, and versatile tool equipped with essential features and technologies that cater to a wide range of tasks. Its combination of strength, efficiency, and ease of use makes it an excellent choice for both DIYers and professionals seeking reliable performance in their projects. Whether inflating tires, powering tools, or completing home improvement tasks, the Craftsman 921.1521 stands ready to meet the challenge.
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