Contactor is an electrical component which helps to control the electrical circuit by switching it ON and OFF. In this article, we will discuss the wiring diagram of a single phase 2 pole contactor. This will provide information about the connections of various wires and terminals in a contactor. By following this wiring diagram, one can easily install a single phase 2 pole contactor in their electrical circuit.
Understanding Single Phase 2 Pole Contactor
A single phase 2 pole contactor is a type of contactor that is used in single phase electrical circuits. It consists of two poles, which can be used for switching the circuit ON and OFF. The contactor has two main components – the coil and the contacts. The coil is responsible for energizing the contactor, while the contacts act as a switch.
When the coil is energized, it creates a magnetic field which pulls the contacts together, completing the circuit. This allows the electrical current to flow through the circuit. When the coil is de-energized, the magnetic field disappears, and the contacts move back to their original position, breaking the circuit.
Wiring Diagram of Single Phase 2 Pole Contactor
Before we start with the wiring diagram, let’s understand the various components of a single phase 2 pole contactor. The contactor consists of the following components:
- Coil
- NO (Normally Open) Contacts
- NC (Normally Closed) Contacts
- Common Terminal
The wiring diagram of a single phase 2 pole contactor is shown in the figure below.
| Terminal | Description | Connection |
| L1 | Line 1 Terminal | Connect to the incoming supply wire |
| L2 | Line 2 Terminal | Connect to the other incoming supply wire |
| T1 | NO Terminal | Connect to the load wire |
| T2 | Common Terminal | Connect to the other end of the load wire |
| T3 | NC Terminal | Leave unconnected |
| A1 | Coil Terminal | Connect to the incoming supply wire |
| A2 | Coil Terminal | Connect to the other incoming supply wire |
Now, let’s understand the connections in detail.
Line Terminals (L1 and L2)
The line terminals are the points where the incoming supply wires are connected. The L1 terminal is connected to one of the incoming supply wires, while the L2 terminal is connected to the other incoming supply wire.
NO Terminal (T1)
The NO terminal is the point where the load wire is connected. When the contactor is energized, the NO contact closes, completing the circuit and allowing the electrical current to flow through the load.
Common Terminal (T2)
The common terminal is connected to the other end of the load wire. When the NO contact closes, the electrical current flows through the load and returns through the common terminal.
NC Terminal (T3)
The NC terminal is not used in a single phase 2 pole contactor. It is used in other types of contactors which have more than two poles.
Coil Terminals (A1 and A2)
The coil terminals are connected to the incoming supply wires. When the supply voltage is applied to the coil, it creates a magnetic field which pulls the contacts together, completing the circuit. The A1 terminal is connected to one of the incoming supply wires, while the A2 terminal is connected to the other incoming supply wire.
FAQs
1. What is a contactor?
Contactor is an electrical component which helps to control the electrical circuit by switching it ON and OFF. It is used in various electrical applications where there is a need to switch the circuit ON and OFF frequently.
2. What is a single phase 2 pole contactor?
A single phase 2 pole contactor is a type of contactor that is used in single phase electrical circuits. It consists of two poles, which can be used for switching the circuit ON and OFF. The contactor has two main components – the coil and the contacts. The coil is responsible for energizing the contactor, while the contacts act as a switch.
3. What is the purpose of a wiring diagram?
A wiring diagram is used to show the various connections of wires and terminals in an electrical circuit. It helps to understand the circuit and provides information about the connections that need to be made. By following a wiring diagram, one can easily install a component in the circuit.
4. Can a single phase 2 pole contactor be used in a three phase circuit?
No, a single phase 2 pole contactor cannot be used in a three phase circuit. It is designed to be used in a single phase circuit only. In a three phase circuit, a three phase contactor is used.
5. What is the difference between NO and NC contacts?
NO (Normally Open) contact is a type of contact that is open when the contactor is de-energized. When the contactor is energized, the NO contact closes, completing the circuit. NC (Normally Closed) contact is a type of contact that is closed when the contactor is de-energized. When the contactor is energized, the NC contact opens, breaking the circuit.
In a single phase 2 pole contactor, only NO contacts are used. NC contacts are not used.
