By limiting the various parameters of the electrical equipment circuit, or taking protective measures to limit the spark discharge energy and heat energy of the circuit, so that the electrical spark and thermal effect generated under the normal operation and the specified fault state can not ignite the explosive mixture of the surrounding environment, so as to achieve electrical explosion-proof, the electrical equipment circuit itself has explosion-proof performance. That is, it is safe from the "essence", so it is called intrinsically safe. Electrical equipment using intrinsic safety circuit is called intrinsically safe electrical equipment.

Because the circuit of the intrinsically safe electrical equipment is itself safe, the sparks, arcs and heat generated will not ignite the explosive mixture of the surrounding environment, so the intrinsically safe electrical equipment does not need a special explosion-proof shell, so that the volume and weight of the equipment can be reduced, and the structure of the equipment can be simplified. At the same time, the transmission line of this type of electrical equipment can be made of gum wire and bare wire, which can save a lot of cables. Therefore, the intrinsic safety type electrical equipment has the characteristics of safety and reliability, simple structure, small size, light weight, low cost, convenient manufacturing and maintenance, and is an ideal explosion-proof electrical equipment. However, because the maximum output power of the intrinsically safe electrical equipment is about 25W, the range of use is limited. At present, intrinsic-safety electrical equipment is mainly used in communication, monitoring, signal and control systems, as well as instruments and meters.

An intrinsically safe power supply provides power for intrinsically safe devices (sensors, transmitters, actuators, etc.). In order for a system or device to meet the conditions of intrinsic safety, the power output must meet the requirements of intrinsic safety, and the overall need to meet the requirements of intrinsic safety after the power supply and the device are connected. The measure to achieve intrinsic safety is to limit the energy of the power supply in various states, that is, the spark discharge energy in normal working conditions and fault conditions. Specific measures include current limit, voltage limit, overvoltage limit.

The intrinsic safety power supply includes input module, isolated DC-DC voltage regulator conversion module (also known as DC-DC power isolation module) intrinsic safety management module and status indicator module. The intrinsic safety management module comprises two current detection units, two voltage detection units and two fast turn-off units. The intrinsic safety management module is the core module. When there is artificial fault or output short-circuit fault or the external load is switched on and off, the intrinsic safety management module ensures that the energy of the generated spark does not cause explosive substances in the ignition environment.