What's the difference between surge, isolator and safety barrier three?

There are many forms of explosion-proof, the most commonly used are explosion-proof and intrinsic safety, and intrinsic safety circuit is composed of on-site intrinsic safety instrumentation + intrinsic safety related equipment and systems, which are indispensable.

The intrinsic safety related equipment commonly used in the circuit refers to the safety grate, which has two types: Zener type and isolation type. Zener type safety grate has only limited energy unit and must be grounded. It has been phased out gradually in practical application. At present, the isolation type safety grate is basically the main type. At the same time, the isolation and signal processing unit are added to limit energy, which can be effective. Improve anti-interference capability and signal processing capability, such as converting 4~20mA to 1~10V.

Isolators are less energy-limiting units in principle than isolation safety grids. They mainly focus on isolation and signal processing. Most isolation safety grids can replace isolators in their functions. Some isolation grids whose power is beyond the scope of intrinsic safety can not do so.

The main function of surge protector SPD is to discharge the lightning to the earth. The functions and uses of the three functions are different.

In terms of shock resistance, the signal ports of isolator and isolator can withstand shock below 1 kV 500A, while SPD has strong shock resistance.