4-20mA Two-Wire Passive Isolated Loop Conditioner with HART

SunYuan  ISO 4-20mA-EHT series HART transmissive 4-20mA two-wire passive isolation conditioner is a signal isolation and conditioning converter module specially designed for industrial instruments and meters, intelligent sensors and transmitters with HART protocol transmission and control, It can convert the input active 4-20mA current signal into an isolated passive control signal output to control the two-wire power supply (explosion-proof mode) 4-20mA current loop, sensor signal acquisition and analog input interface active load matching, effectively solving the collection of active 4-20mA current signals and two-wire current loop power supply circuit interface of the conflict between different power supply circuit. The product combines the advantages of signal isolation conditioning and HART communication technology, which can realize the signal isolation conversion and on-line accurate measurement and control between two-wire sensors, instruments and transmitters in the industrial field. It is widely used in the fields of intelligent sensors, intelligent control instruments and transmitters, industrial control intelligentization, safety isolation barriers for electric power and medical equipments, industrial robots, chemical fuels, and safety equipments for nuclear power.

    ISO 4-20mA-EHT module is mainly used for the isolation and conditioning of 4-20mA signals of intelligent sensors in industrial field and the transmission of HART signals, The product adopts high-efficiency circuit power theft patented technology, without independent power supply two-wire circuit power supply output mode can save two power lines, simplify the user's power design and site wiring costs. The product adopts advanced digital technology and electromagnetic isolation technology, in the realization of bidirectional communication HART protocol signals at the same time with the isolation of 4-20mA analog signal input and output functions.

    The ISO 4-20mA-EHT output is designed for a 2-wire power loop with 24VDC and sampling resistors (2-wire instrumentation) in series, matching the analog input ports of current analog input interface boards (host computers), PLCs, DCSs, or other instrumentation with active loads commonly used in the industrial field. The very small input equivalent resistance can be collected from the sensor output loop to the current signal voltage value to reach an ultra-wide range (5 ~ 32VDC) to meet the user without external auxiliary power supply to realize the need for long-distance, distortion-free signal transmission. The module integrates HART digital signal isolation transmission circuit and active 4-20mA current signal to passive output isolation conditioning circuit, HART signal bidirectional isolation transmission circuit, etc., which can support the communication between on-site intelligent sensors and instrumentation and DCS centralized system in the control room, and give full play to the double advantages of digital and analog signals. The product is very easy to use, only need to connect an external 2KΩ multi-turn potentiometer for ADJ calibration, can realize the two-wire 4-20mA signal isolation, transmission and acquisition control.  The internal integration process and new technology isolation measures enable the module to achieve 3KVDC insulation voltage and industrial grade wide temperature, humidity, vibration field harsh environment requirements.The products have IC package PCB board welding module mode and DIN35 standard rail-mounted mode, rail-mounted mode can realize the signal 1-input&1-output, 2-input&2-output and multi-channel isolation transmission transformation function, the user can configure the products according to the needs of the site.