Comparison of SSR and SCR in Circuit Control

Comparison of SSR and SCR in Circuit Control

SSR：

The high-temperature aging test chamber SSR refers to a solid-state relay, which is a new type of contactless switch device composed entirely of electronic components. It has the advantages of high reliability, long life, low noise, fast switching speed, strong anti-interference ability, vibration resistance, impact resistance, moisture resistance, moisture resistance, corrosion resistance, and compatibility with logic circuits such as TTL and CMOS. It is gradually being accepted by more and more application fields. In the field of reactive power compensation control, the traditional AC contactor for controlling capacitive loads has been greatly challenged by the operational requirements of maintenance free equipment. Although the universal AC SSR is favored by users for its unique zero crossing conductivity, it is difficult to meet the control requirements for capacitive loads with high voltage and high impulse current, which restricts the promotion and application of SSR in this field.

SSR can be divided into two types: AC and DC. It triggers the thyristor (unidirectional or bidirectional thyristor) with a lower voltage (DC3V~32V) to make its load end conductive, outputting higher DC or AC, thus achieving the goal of controlling higher voltage or stronger current through lower voltage. Compared with ordinary AC contactors, it does not generate electrical sparks during conduction and cutoff.

SCR:

SCR power regulators are widely used in various heating scenarios due to their efficient power control capability and regulation accuracy. The following are some common application areas:

1. Electric furnace industry. SCR power regulators are widely used in various electric furnace applications, covering annealing, drying, quenching, sintering and many other furnace types, flexibly meeting diverse heating processes and strict temperature control requirements.

2. Mechanical equipment. The SCR power regulator, with its temperature control function, achieves accurate management of heating temperature with the help of internal heating components, effectively ensuring the quality of processed products meets standards.

Especially in the fields of precision machinery such as packaging and textiles, its value is particularly significant, safeguarding efficient and high-quality production processes.

3. Glass industry. In processes such as fiberglass, glass forming, and glass melting, the SCR power regulator helps improve the quality of the final product through temperature control.

4. Automotive industry. SCR power regulators play a core role in the automotive manufacturing industry, relying on their excellent temperature control accuracy to effectively improve the efficiency of heat treatment and coating processes, laying a solid foundation for the high-quality development of the automotive industry.

5. Chemical industry. SCR power regulators in the chemical industry can optimize reaction efficiency, ensure product quality, achieve energy-saving automation, and ensure long production and equipment life through accurate temperature control.

Comparison Table of SSR and SCR:

Overall, although the universal AC SSR is favored by users for its unique zero crossing conductivity, it is difficult to meet the control requirements for capacitive loads with high voltage and high impulse current, which restricts the promotion and application of SSR in this field.

SCR can continuously adjust the output voltage and is suitable for applications that require fine control. It can adjust power through voltage regulation and has little impact on the power grid. Therefore, it is usually used in high-power electric heating systems or situations that require continuous adjustment of output voltage.