Table of Contents
How does a magnetic motor starter work?
Magnetic starters rely on electromagnets to function. They have an electromagnetically operated set of contacts that starts and stops the attached motor load, and an overload relay. The overload relay opens the control voltage to the starter coil if it detects an overload on a motor.
What is an IEC starter?
IEC motor starters are used to operate polyphase induction motors and protect them against running or stalled overcurrents, and feature components that meet IEC design standards. Configurations include open frame units or starters enclosed in metallic or non-metallic pre-wired enclosures.
What is a motor line starter?
A DOL starter (also known as a direct on line starter or across the line starter) is a method of starting a 3 phase induction motor. In a DOL Starter, an induction motor is connected directly across its 3-phase supply, and the DOL starter applies the full line voltage to the motor terminals.
What are the advantages of magnetic motor starter?
They facilitate the starting and stopping of the motor. The starters are rated by power (horsepower, kilowatt) and current (amperes). They provide the necessary overload protection for the motor. The electrical device facilitates remote on/off control feature.
What is IEC and NEMA?
In measuring electric motors and motor controls, there are two standards in use: the National Electrical Manufacturers Association (NEMA) and the International Electrotechnical Commission (IEC). NEMA is mostly used in North America while IEC is used in most parts of the world.
What does IEC mean?
the International Electrotechnical Commission
IEC stands for the International Electrotechnical Commission: An “organization that prepares and publishes international standards for all electrical, electronic and related technologies.”
What is the main difference between a contractor and a magnetic motor starter?
The contactor applies voltage to a contactor coil to close the contacts and to supply and interrupt power to the circuit. A motor starter is simply a contactor PLUS an overload relay and is rated by motor HP or amperage.
What is the difference between a magnetic motor starter from that of the manual motor starter?
Magnetic. Magnetic motor starters rely on electromagnets to close and hold contactors rather than the use of mechanical latching of on/off switches as used in manual starters. They are used in across-the-line applications and as reduced voltage starters for single- and three-phase motors.
What is a full voltage starter?
Full-voltage starters, also referred to as across-the-line starters or direct-on-line (DOL) starters, are full-voltage non-reversing (FVNR) and connect the motor to a power line. Manual starters are limited to single-phase motors through about 5 HP at 320 VAC and three-phase through 10 HP at 460 and 575 VAC.
What does across the line starter mean?
A direct on line (DOL) or across the line starter applies the full line voltage to the motor terminals. Solid-state direct on line starters also exist. A direct on line starter can be used if the high inrush current of the motor does not cause excessive voltage drop in the supply circuit.