Signal isolation module types

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Signal isolation modules are usually classified by function, and are generally divided into three categories: signal isolators, power distributers, and safety barriers. 1. Signal isolators are used in industrial production to increase the load capacity of instruments, ensure that instruments connected to the same signal do not interfere with each other, and improve electrical safety. The input voltage signals, current signals, frequency signals, resistance signals, etc. need to be collected, amplified, processed, and subjected to anti-interference treatment, before isolated current and voltage signals are output for safe use by secondary instruments, PLCs, and DCS systems. Based on their functionality, isolators are further divided into single-input single-output signal isolators, single-input dual-output signal isolators, single-input four-output signal isolators, and dual-input dual-output signal isolators. 2. Distributor: The distributor supplies 24VDC power to the two-wire transmitters. It also collects, amplifies, processes the 4-20mA current signals generated by the transmitters, and applies anti-interference measures; thereafter, it outputs isolated current and voltage signals for use by subsequent secondary instruments, PLCs, and DCS systems. Based on their function, distribution units are further divided into single-input single-output distribution units, single-input dual-output distribution units, and dual-input dual-output signal isolators. The same signal isolator is compatible with both signal distribution and distribution functions; when used as a distributor, it can be paired with two-wire, three-wire, and four-wire transmitters. 3. Safety barriers: In some special industrial environments (such as gas companies and chemical plants), not only is two-wire transmission required to provide both power supply and signal isolation, but there is also a need for properties that prevent the generation of dangerous sparks. These features are necessary to effectively control the power supply, preventing ignition between the power supply, signals, and ground. By implementing current limiting and voltage reduction measures on both the signal and power circuits, it is possible to keep the energy entering hazardous areas within safe limits. This is where safety barriers come in handy. Safety barriers are usually subdivided into operating-end safety barriers and sensing-end safety barriers.