Regarding intrinsically safe instruments
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Regarding intrinsically safe instruments? 1. For intrinsically safe systems, are safety barriers required for both the input and output? For example, the pressure control system: the pressure transmitter feeds into the DCS along with a safety barrier ； DCS to pressure control valve with safety barrier? 2. Under normal circumstances, which type of safety barrier is used more frequently? Resistive, Zener, relay-based, opto-isolated, or transformer-based? 3. What types of safety barriers are generally used to measure temperature, pressure, liquid level, flow rate, and composition? 4. Some intrinsically safe instruments, such as pressure transmitters, are inherently of the intrinsically safe type; is it still necessary to add a safety barrier during signal transmission?
Inherently safe instruments should be such that they do not generate unsafe sparks in hazardous areas, and unsafe sparks from safe areas cannot penetrate into hazardous areas.
Intrinsic safety means that the output energy in the hazardous area is not sufficient to ignite explosive substances; the fundamental solution is to limit that energy
Intrinsic safety instruments need to be used in conjunction with safety barriers to form an intrinsic safety system; the safety barrier separates the field signals from the system, which is why safety barriers are required for both inputs and outputs.
Inherently safe instruments are used in high-hazard environments, and the function of safety barriers is to protect the connection between the safe control area and the unsafe control area.
Generally, isolation grids are used more often.
Firstly, generally, when intrinsically safe instruments are connected to a DCS, a safety barrier may be required, while flameproof types usually do not need one； Secondly, not all instruments will have signals from the DCS (AO, DO)
Generally, isolation grids are used more often. Zinasan is used by very few people these days because it needs to be grounded.
In hazardous areas, the instruments themselves do not generate unsafe sparks, while unsafe sparks from safe areas cannot penetrate into hazardous areas
4# inssun: For example, if my pressure transmitter is of the intrinsically safe type, do I need to use a safety barrier during the transmission of the pressure signal to the DCS?
I want 10# rujimmy! The entire circuit must be intrinsically safe