Many contactor manufacturers use the designations A1 and A2 for the terminals that connect power to the magnetic coil. Likewise, many manufacturers use the designations 13 and 14 for the terminals of normally open auxiliary contacts. Auxiliary contacts are operated by the magnetic coil just like the main contacts.

What is A1 and A2 on a contactor?

What Do A1 and A2 Mean on a Contactor? A1 and A2 on a contactor typically refer to either end of the electromagnetic coil assembly. Most contactor manufacturers use A1 and A2 to designate the two terminals connecting electrical power to the contactor's magnetic coil.

What do numbers on contactor mean?

These auxiliary contacts (also called control contacts) each have an order number and a function number. The first number is used consecutively (order number) and the second number specifies the type of contact (function number).

What is the difference between A1 and A2 in electrical circuit?

One side of the contactor coil (A2) is connected directly to one of the incoming power lines. The other side of the coil (A1) has two possible pathways to complete a connection to the other incoming power line.

What is AC1 and AC3 contactor?

The difference between AC1 and AC3 contactors is AC1 contactors are used for general purpose resistive loads but AC3 contactors are used for high inductive, squirrel cage motor switching. The rating of AC3 is lower than AC1. Because AC3 switches high inrush currents.

What is Contactor? | All About Contactors | Wiring Diagram

Does a contactor need a neutral?

You still need a neutral going to the load. We need both hot and neutral at the coil side of the relay to make the coil pull in to make the contact.

How do I spec my contactor?

There are 5 primary things to consider when determining how to size a contactor for your application:

1. Full Load Amperage at Line Voltage. The first item to consider is the load, which is measured in amperes. ...
2. Contactor Coil Voltage. ...
3. IEC Utilization Categories. ...
4. Reversing vs Non-Reversing Contactors. ...
5. Auxiliary Contacts.

What does L and T stand for on a contactor?

With "L" 1,2,3, the L = "Line", meaning the incoming supply line. For the load side, "L" already had a different meaning, so the the label is T 1,2,3, with "T" = Terminus, meaning the exit point, ie going to the last thing connected in the circuit.

What are the two basic types of contactors?

There are different types of contacts in a contactor, and they are; auxiliary contact, power contact, and contact spring. The power contact has two types that are; stationary and movable contact.

How do you connect a contactor to a switch?

Contactor Connection Procedure

1. Generally the magnetic coil of a contactor is designed to operate at a low voltage such as 230V AC, 110V AC, 24V DC, etc. ...
2. Connect the main power supply terminal with the incoming terminals of the contactor.
3. Connect the load with the outgoing terminals of the contactor.

How does a 3 phase contactor work?

Operating Principle of a Contactor:The current passing through the contactor excites the electromagnet. The excited electromagnet produces a magnetic field, causing the contactor core to move the armature. A normally closed (NC) contact completes the circuit between the fixed contacts and the moving contacts.

What is a 3 pole contactor?

3 pole contactors are typically used in commercial applications. These contactors utilize three wires to control electrical current direction.

What is NO and NC In contactor?

Normally open(NO) and Normally closed (NC) are terms used to define the states of switches, sensors or relay contacts under when its coil is not excited. It is the fundamental of process automation.

Why is there no neutral in 3 phase?

Fact 3: The current in the neutral wire is the phasor sum of all the line currents. In a balanced system, when all currents and their power factors are the same, the phasor sum of all line currents is 0A. That's the reason why there is no need for neutral wire in a balanced system.

What does AC1 mean on a contactor?

Resolution: AC-1 - This category applies to all AC loads where the power factor is more than 0.95. These are primarily non-inductive or slightly inductive loads, such as resistive loads. Breaking the arc remains easy with minimal arcing and contact wear.

What does AC15 mean?

Rated load AC15: The maximum AC inductive load (in VA) that a contact can make, carry and break repeatedly, according to classification AC15 (see Table 1), called “AC inductive load” in EN 61810-1:2008, Annex B. Single-phase motor rating: The nominal value of motor power that a relay can switch.

What is AC 21A?

AC-20B * Making and breaking without load. AC-21A. AC-21B. Switching resistive loads including low overloads.