What is a plugging switch?

What is a plugging switch?

The plugging switch, through a magnetic control, allows reverse power to be applied to a rotating motor and automatically removes this power when the motor approaches zero speed. The lockout device, supplied with some forms, will prevent false starting by manual rotation of the motor shaft.

What is a zero speed plugging switch?

A zero-speed switch is a switch that is activated by centrifugal forces and is attached either directly or via a belt to the shaft of the motor. To provide plugging action, the zero-speed switch must be wired normally open so that any motion of the motor shaft will cause the contacts to change their state and close.

Is also known as plugging switch?

Plugging — sometimes referred to as “reverse current braking” — is possible on both DC motors and AC induction motors.

How does a control circuit work?

A control circuit is used to ensure that the motor is started and stopped in a safe manner for both the operator and the equipment. The thermostat is part of a low-voltage control circuit that controls a relay that actually energizes and de-energizes the power circuit to the air conditioning compressor.

What is anti plugging in electrical?

Some circuits use this plugging action to quickly decelerate and stop a motor. If the sudden reversal of a motor is considered undesirable, then our control circuit can be designed to provide anti-plugging , which can be provided by either a normally closed zero-speed switch or off-delay timer relays.

What is dynamic braking system?

Definition of dynamic braking : a system of braking (as in electric trains or machinery) in which the driving motor is converted into a generator and is driven by the kinetic energy of the vehicle thus exerting a retarding force.

What is DC dynamic braking?

Dynamic Braking It is also known as Rheostatic braking. In this type of braking, the DC motor is disconnected from the supply and a braking resistor Rb is immediately connected across the armature. The motor will now work as a generator and produces the braking torque.

What is the working principle of Zss?

Zero speed switches (ZSS) also known as Speed Actuating Sensing Switches are used to detect the stoppage or unacceptably slow movement of a rotating shaft. Generally its applications are in various machines, conveyors, power plants, and industries involving the production of cement, sugar, textiles, paper, etc.

What is regenerative braking in DC motors?

Regenerative braking is used when the driven load causes the DC motor to run at speeds higher than its no-load speed. This results in the reversing of the motor current and turns it into an electric generator. Regenerative braking also results in some of the energy generated returning to the source supply.

What are the three types of circuit control devices?

There are three type of common circuit control devices; switches, relays and solenoids.

What is the use of Zss in conveyor belt?

Zero speed switches (ZSS) also known as Speed Actuating Sensing Switches are used to detect whether a rotating shaft is turning (even at very slow speeds) in various machines, conveyors, power plants, and in industries involving the production of cement, sugar, textiles, paper, etc.

What is the purpose of a plugging action?

Some circuits use this plugging action to quickly decelerate and stop a motor. For example, in certain machine-tool operations where instantly stopping motor drives may be necessary. We will be examining a in greater detail further in this text.

Why do lathes have anti-plugging features?

Most lathes (cheap and expensive alike) which have solid state controls have anti-plugging features becuase otherwise the drives can be damaged. A three-phase ac motor can be plug reversed by exchanging any two leads.

What are the disadvantages of plugging?

Plugging is also a very inefficient method of stopping and, therefore, generates significant heat. Despite these drawbacks, plugging is used in equipment such as elevators, cranes, presses, and mills, where a rapid stop of the motor (with or without reversal) is required. Filed Under: AC Motors, DC Motors, FAQs + basics, Featured, Motors

Is plugging possible on a DC motor?

Plugging — sometimes referred to as “reverse current braking” — is possible on both DC motors and AC induction motors. For DC motors, plugging is achieved by reversing the polarity of the armature voltage.