MAGNETIC STARTER FOR 7.5HP SINGLE PHASE 230V ELECTRIC MOTORS – EATON

• EATON 7.5HP MAGNETIC MOTOR STARTER FOR 7.5HP SINGLE PHASE 230V ELECTRIC MOTORS
• EQUIPPED WITH AN ADJUSTABLE OVERLOAD RELAY FROM 24 – 40 AMPS
• 40 AMP CONTACTOR, 208-230V COIL AND NEMA 1 METALLIC ENCLOSURE, REPLACEMENT CHICAGO PNEUMATIC RCP-C7581V, RCP-C7581VS
• ENCLOSURE 10″ HEIGHT x 6″ WIDTH x 6″ DEPTH, 12 MONTH FACTORY WARRANTY. PROFESSIONAL INSTALLATION REQUIRED.

What is a Magnetic Starter and How Does It Work?

A magnetic starter is essentially the control center for an electric motor, particularly in systems like air compressors. Here's how it functions:

Basic Operation: Magnetic starters are electromechanical devices comprising a contactor and an overload relay. When activated, the contactor, which is an electromagnet, pulls in the contacts to connect the electrical circuit, allowing power to flow to the motor.
Overload Protection:
Thermal Overload Relays: These use bimetallic strips that heat up with current flow. If the current exceeds safe levels, the strips bend, triggering the relay to open the circuit, thus protecting the motor from overload.
Adjustable Overload Relays: These allow you to set the trip point at a specific amperage, providing a more tailored protection based on the motor's specifications.
Duty Cycle: Properly sized with the compressor pump, magnetic starters enable the motor to operate at a 100% duty cycle, meaning it can run continuously without overheating.

Why Do You Need a Magnetic Starter?

Motor Protection: Magnetic starters protect motors from power surges and overload conditions by allowing current to flow smoothly through robust contact points.
Efficiency and Durability: Unlike direct wiring through a pressure switch, which has smaller contacts, magnetic starters handle the high current demands when the motor starts, preventing motor strain, potential tripping of circuit breakers, and premature wear.
Pressure Switch Limitation: Direct wiring via a pressure switch can lead to the motor being starved of power, causing it to work harder, which can degrade the motor quickly due to the small contact points in the switch.

Selecting the Right Magnetic Starter:

Check the Data Plate: When choosing a magnetic starter, refer to the motor's data plate:
Full Load Amps (FLA): This is the current the motor draws under full load.
Service Factor (SF): Adjust the overload protection based on this:
For a 1.0 service factor, set overload protection 1% to 5% above FLA.
For a 1.15 service factor, set it 10% to 15% above FLA.
Voltage Considerations: Ensure the incoming voltage matches or is suitable for the motor's rated voltage. Variations like 208-230V might affect the service factor, so adjust accordingly when choosing or setting your starter.

Magnetic starters are recommended by professionals for their robust protection and operational efficiency, ensuring your equipment runs safely and reliably.