Skip to main content

SOLID- STATE RELAYS (SSR) TECHNICAL EXPLANATION

Scheme: Solid state relay

WHAT IS A SOLID STATE RELAY?
A Solid State Relay (SSR) is a relay that does not have a moving contact. In terms of operation, SSRs are not very different from mechanical relays that have moving contacts. SSRs, however, employ semiconductor switching elements, such as thyristors, triacs, diodes, and transistors.
DIFFERENCE BETWEEN SSR AND MECHANICAL RELAY:
SSRs (solid-state relays) have no movable contacts. SSRs are not very different in general operation from mechanical relays that have movable contacts. SSRs, however, employ semiconductor switching elements, such as thyristors, triacs, diodes, and transistors. Furthermore, SSRs employ optical semiconductors called photocouplers to isolate input (control) and output (load) signals. Photocouplers change electric signals into optical signals and transmit the signals through space, thus fully isolating the input and output sections while transferring the signals at high speed. SSRs consist of electronic parts with no mechanical contacts. Therefore, SSRs have a variety of features that mechanical relays do not incorporate. The greatest feature of SSRs is that SSRs do not use switching contacts that will physically wear out.
                                 
Difference between SSR and mechanical relay
FEATURES OF SSR:
1.Enable high-speed and high-frequency switching.
2.Unlimited number of switching operations.
3.Consist of semiconductors, so there is no contact erosion caused by switching.
4.Zero cross function.
5.No operation noise.

CLASSIFICATION OF SSR
(Based on Application)
1.Heater Control
These SSRs are applicable to machines which require highly sensitive temperature control for turning heaters ON and OFF, such as molding equipment, packaging machines, and solderers. They meet the high-capacity, high ON/OFF frequency requirements of heater control.

2.Motor Control
These SSRs are applicable to machines which require motor inching operation and reversible operation, such as machine tools, conveyors, and packaging equipment. They have high-speed response time and high ON/OFF frequency, required for inching and reversible operation.

3.I/O
These SSRs meet the requirements for isolated transmission of control output from PCs and Position Controllers to an actuator.

4.Amusement Machines
These SSRs have high ON/OFF frequency, noiseless operation, and when compared to mechanical relays, have greater resistance to vibration, shock, dust and dirt, and gas, making them ideal for situations where these factors are important.

5.Panel-mounted Interfaces
These SSRs are the same shape as general-purpose relays, they have the same sockets and can be mounted according to their respective shapes. They are ideal for interface applications where high-frequency switching is required, and can also be used in a wide variety of general-purpose applications, such as directly switching loads.

APPLICATION CIRCUIT EXAMPLES:
1.Connection to a sensor

connection to a sensor
        
2.Switching control of an incandescent lamp     
CONN
switching control of an incandescent lamp
                      
3.Temperature control of an electric furnace
Temperature control of an electric furnace
                                
Labels:
Location: India

Comments

Post a Comment

You May like This

Speed sensor: Working principle | Types | Applications

Typical view of Speed sensor   What is speed sensor? The speed sensor belongs to the tachometer category. It is a device used to measure the speed of wheel rotation of a vehicle. The speed sensor was initially used to replace the mechanical connection between the rotating wheels and the speedometer, reducing the use of cables and facilitating construction by reducing rotating parts. These sensors also generate data that allows automatic driving to take place. The speed of an object is the magnitude of the change of its position; it is thus a scalar quantity. The average speed of an object in an interval of time is the distance travelled by the object divided by the duration of the interval; the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero. Speed has the dimensions of distance divided by time. The SI unit of speed is the meter per second, but the most common unit of speed in everyday usage is the kilometer per h...
Post a Comment
Read more

Definition of Logic Gates | Positive and Negative Logic | Truth table | Types of Logic Gates

  Definition of a Logic Gate: "A logic gate is an electronic circuit which makes logic decisions". It has one output and one or more inputs. The output signal appears only for certain combinations of input signals. Logic gates are the basic building blocks from which most of the digital systems are built up. They implement the hardware logic function based on the logical algebra developed by George Boole which is called Boolean algebra in his honour. A unique characteristic of the Boolean algebra is that variables used in it can assume only one of the two values i.e. either 0 or 1. Hence, every variable is either a 0 or a 1.
Post a Comment
Read more

Complete paper machine descriptions and explanations

  History of paper a brief: Paper was first discovered in ancient China, and the first material used for writing was a "tree" called papyrus. These papyrus materials are not defined as real paper. It was first documented in China during the Eastern Han period (25-220 CE), usually told to a court official. Spread to the Islamic world during the 8th century. The algorithm of the 11th century was brought to medieval Europe. Later in the 19th century came the Western developments in the field of paper with the invention of wood-based papers.
Post a Comment
Read more

What is Hall effect sensor? Working principle | Types and Applications

Hall sensor symbol What is a Hall effect sensor? Hall effect sensor is defined as a device which use the principle to convert magnetically encoded signals into electrical signals. Which means Hall effect sensor output voltage is directly proportional to the magnetic field strength. Hall effect sensors are used in automotive systems for sensing distance, position, speed detection, and current sensing applications.
Post a Comment
Read more