What is the classification and application of safety barriers?

Hello lz, I am the marketer of Suzhou Beijiafu explosion-proof electric.

The common safety barrier structure forms are divided into Zener safety barriers and isolation safety barriers. So what are the differences? The following is a detailed introduction to the two different types of safety barriers.

First, we will introduce the isolation barrier.

A circuit structure that electrically isolates the input, output, and power supply from each other, and complies with the requirements of intrinsically safe energy-limiting. Although it is more expensive than Zener security, its outstanding advantages in performance bring greater benefits to the user's application:

1.Due to the use of three-way isolation, there is no need for system grounding lines, which brings great convenience to design and on-site construction.

2.The requirements for instrumentation in hazardous areas are greatly reduced, and there is no need to use isolated instruments on site.

3.Because the signal line does not need to be grounded, the stability and anti-interference ability of the detection and control loop signal are greatly enhanced, so as to improve the reliability of the whole system.

4.The isolated full gate has a stronger input signal processing ability, which can accept and process thermocouples, RTDs, frequencies and other signals, which cannot be achieved by Zener safety barriers.

5.The isolation barrier can output two signals that are isolated from each other to provide two devices using the same signal source, and ensure that the signals of the two devices do not interfere with each other, and at the same time improve the electrical safety insulation performance of the connected equipment between each other.

Secondly Zener type safety barrier:

Fast fuses, current-limiting resistors, or voltage-limiting diodes are used in the circuit to limit the input electrical energy and thus ensure the energy output to the danger zone. Its principle is simple, the circuit is easy to implement, and it is inexpensive, but because of the defects of its own principle, the reliability in its application is greatly affected, and its application scope is limited, and the reasons are as follows:

The installation position must have a very reliable grounding system, and the grounding resistance of the Zener type safety barrier must be less than 1, otherwise it will lose the explosion-proof safety protection performance, obviously such requirements are very demanding and difficult to guarantee in practical engineering applications.

It is required that the field instrument from the hazardous area must be isolated, otherwise the signal cannot be transmitted correctly after being connected to the ground through the grounding terminal of the Zener safety barrier, and due to the signal grounding, the signal anti-interference ability is directly reduced, which affects the stability of the system.

The Zener safety barrier has a great impact on the power supply, and it is also easy to cause damage to the Zener safety barrier due to the fluctuation of the power supply.

Hope it helps you with your questions, hopefully.

Since its birth, the safety barrier has experienced decades of development, extending several categories and dozens of varieties. In general, the industry classifies safety barriers according to the following methods.

First, from the use of standards, and application occasions, it can be divided into mine standard safety barriers and factory standard safety barriers, and factory standard safety barriers can be divided into combustible gas environmental safety barriers and dust environmental safety barriers.

Second, from its own structural characteristics and implementation form, it is divided into Zener type and isolated safety barrier, and the isolated safety barrier can be divided into photoelectric isolation safety barrier and magnetoelectric isolation safety barrier.

Third, from the power supply mode of the safety barrier, it can be divided into independent power supply safety barrier (also known as active safety barrier) and loop power supply safety barrier (also known as passive safety barrier).

Fourth, from whether MCU is used or not, it is divided into intelligent safety barriers and non-intelligent safety barriers.

Fifth, from the explosion-proof level reached, it can be divided into IIC, IIB, IIA level safety barriers.

Sixth, from the safety factor achieved, it can be divided into IA type safety barrier (safety factor) and IB type safety barrier (safety factor.

Seventh, from the function in the system, it can be divided into input type safety barrier, and output type safety barrier (generally with the control room as a reference).

Eighth, in terms of the type of signal transmitted, it can be divided into analog safety barrier, switching safety barrier, communication safety barrier, temperature safety barrier, frequency signal safety barrier, etc.

Ninth, from whether it can be automatically restored from the fault state to the normal state, it can be divided into self-recovery safety barrier and non-self-recovery safety barrier.

In short, there are many classification methods for safety barriers, and according to different working conditions and different requirements, it is necessary to choose the appropriate safety barrier from different angles. If the customer is in contact for the first time, you can apply for the technical support of the manufacturer, so as to better choose the right safety barrier.