Key words: signal isolator ,two-wire signal isolator , passive signal isolator,  field application of signal isolator

Reading Guidance：Passive，In the aspect of electronics ,it means that the circuit can work when there is a signal without adding power supply. We usually refer to devices that work without a power supply as passive devices , and commonly used passive components in circuits are diodes, resistors, inductors and capacitors etc.The device in the circuit that needs an external auxiliary power supply to work normally is called an active device, and active devices are generally used to be isolate, amplify, convert and transmit signals etc. Commonly used active devices including the transistors, power amplifiers, signal isolators, isolation amplifiers, field effect transistors, thyristors and other devices. Sunyuan Technology has launched a series of low cost & small volume passive (no external auxiliary power supply) analog signal isolator these new products are provided to sensor and instrumentation manufacturers and industrial Internet system integration design engineers. According to the current industrial Internet matching needs of various sensors, transmitters and PLC, DCS systems in the industrial field, Here we recommends several new two-wire 4-20mA output passive analog signal isolators matching technical solutions, which are provided to manufacturers and industrial Internet system integration engineers for reference when they selecting and applying signal isolators on site.

The application one of Passive Signal Isolator： Passive DC single and bidirectional  voltage/ current, electronic ruler displacement resistance signal to two-wire current signal isolator

Passive displacement resistance signal (ISO R-O), analog voltage signal (ISO U-O), analog current signal isolator (ISO A-O) transmitter which is the industry's smallest low cost passive loop fed analog signal isolation transmitter IC. The IC has loop feeding technology with a unique high-efficiency signal coupling transformer , which provides power supply through the back-stage current output loop feeding method and without the need for an external working power supply.The IC is matched with sensors, instrumentation, PLC/DCS in the design solution, and can adapt to analog voltage, current or displacement resistance signal input of various specifications, and amplify the active signal of the two-wire/three-wire/four-wire general sensor in the industrial field After conditioning and isolation transmission, it outputs two-wire analog current signals with various parameters such as 4~20mA/2-10mA/4-12mA/4-8mA/12-20mA.The core devices in the technical solution: passive displacement resistance signal (ISO R-O), analog voltage signal (ISO U-O), current signal (ISO A-O) The transmitter is designed as a high-precision, small-volume standard SIP12 Pin flame retardant IC package ,they adopts a unique magnetic and electrical isolation coupling method and high-efficiency post-stage feeding technology, which can realize DC voltage, current, unidirectional and bidirectional signals, angular displacement, electronic ruler, potentiometer and other analog signals to the two-wire loop feeding current The precise isolation and conversion of the ring signal is matched with the standard analog input ports of various types of instruments (such as PLC, DCS, FCS).The core products of the solution including the small volume IC packaged ,PCB board installation and DIN35 standard rail-mounted installation. The DIN rail-mounted type installation method can realize the isolation and conversion function of signal 1-input&1-output, 1-input&2-output, 1-input&3-output, 2-input&2-output, four-way, eight-way and sixteen-way signal at the industrial site. The customer they can choice a technical solution according to their requirements.

Detailed technical information：https://www.sunyuansz.com/uploads/soft/210811/2-210Q1103Q2.pdf
 

The application two of Passive Signal Isolator :Passive low cost, small size two-wire 4-20mA (0-20mA) current loop analog signal isolator

Two-Wire Passive ISO 4-20mA (SIP12 Pin Package) and ISOS 4-20mA (SIP7 Pin Package) 4-20mA Current Loop Signal Isolator, It is a passive signal isolation module with 4-20mA (0-20mA) current signal input at the front stage and 4-20mA (0-20mA) current signal output at the rear stage.，The solution adopts the unique electromagnetic isolation mode and high efficiency input loop stealing technology, which solves the dependence of the current signal isolation between the instrument and the sensor on the power supply effectively , and realizes the 4-20mA (0-20mA) standard signal high precision and high linearity isolation. the passive signal isolator obtains energy from the current loop of the sensor In the solution design, and outputs an active 4-20mA analog signal after isolation to drive or control instrumentation, PLC, and DCS devices.The core products of the solution including the small volume IC packaged ,PCB board installation and DIN35 standard rail-mounted installation. The DIN rail-mounted type installation method can realize the isolation and conversion function of signal 1-input&1-output, 2-input&2-output, 3-input&3-output etc multi-channels signal isolation&convert function. The customer they can choice a technical solution according to their requirements.

Detailed technical information：：https://www.sunyuansz.com/uploads/soft/210811/2-210Q1102924.pdf

The application three of Passive Signal Isolator :Passive low cost, small size two-wire 4-20mA loop-fed analog signal isolator
ISO 4-20mA-F (SIP12 Pin) and ISOS 4-20mA-F (SIP7 Pin package) 4-20mA current loop signal isolation distributor is a two-wire loop powered isolation module. It supplies power to the front-stage two-wire equipment through the back-stage feeding method, and receives the 4-20mA current signal output from the two-wire equipment. and it outputs a 4-20mA current signal for the sensor to work after the module is isolated, This solution adopts a unique electromagnetic isolation mode and high-efficiency post-feeding technology, which can solves the dependence of current signal isolation on the power supply effectively, realizes the accurate isolation and transmission of standard signals of 4~20mA, and can be connected with the two-wire of various instruments. control loop powered analog input port (such as PLC, DCS system, etc.).

Detailed technical information：https://www.sunyuansz.com/uploads/soft/210811/2-210Q1102521.pdf

 
The Applications four of passive Signal Isolator  :Passive low cost, small volume analog voltage to two-wire 4-20mA current signal V/I conversion signal isolator
ISO V-4-20mA (SIP12 Pin) and ISOS V-4-20mA (SIP 7Pin) passive V/I conversion analog signal isolation transmitter is a signal Isolated transmitter module with a voltage input, two-wire current output loop-powered.The isolation transmitter IC can provide a set of 5V(3mA) power supply for function extension in next step current loop powered mode. And it receives the voltage signal from the input terminal and converts it into standard 4-20mA 2-wire current signal. This solution adopts a unique electromagnetic isolation mode and high-efficiency post-feeding technology to achieve precise isolation and conversion of voltage signals to 4-20mA standard signals, and can be connected with the analog input ports of various instruments (such as PLC, DCS systems, etc. match.The technical solution is very convenient to use, and can realize the isolation and transmission of voltage signals of voltage signal input, displacement potentiometers and other sensors that require distribution or bridge (weighing) detection circuits without any additional devices.

Detailed technical information：https://www.sunyuansz.com/uploads/soft/210811/2-210Q1103110.pdf

The application five of passive Signal Isolator:  Passive low-cost two-wire 4-20mA current to analog voltage signal I/V conversion signal isolator

ISO 4-20mA-O series (SIP12 Pin package) two-wire passive 4-20mA to voltage signal isolation converter can isolate and convert the input active 4-20mA current signal into a voltage signal I/V conversion output.The solution adopts the two-wire input loop power supply mode, and has a unique high-efficiency signal loop stealing technology, which does not require an external working power supply, which greatly simplifies the user's design and reduces the user's wiring cost. The module including a current signal modulation and demodulation circuit, a signal coupling isolation conversion circuit, a power inverter circuit, a subtraction circuit, a buffer processing output circuit, etc., with a small input equivalent resistance, it not only realize the conversion between current and voltage signal , it also operates in low heat and passive mode to meet the application requirements in A/D interface data acquisition and signal conversion. It greatly reduce user's cost and the internal resource consumption in choosing microprocessor and provide simplest solutions to the developers.

Detailed technical information：https://www.sunyuansz.com/uploads/soft/210811/2-210Q1102952.pdf

The application six of two-wire signal isolator :Passive low cost, small size two-wire 4-20mA current loop signal isolator

 ISO 4-20mA-E (SIP12 Pin package) and ISOS 4-20mA-E (SIP7 Pin) two-wire passive 4-20mA analog isolation conditioning controller, which can convert input active 4-20mA current signal into The isolated passive control signal output is used to control the 4-20mA current loop of the two-wire loop power supply (explosion-proof mode) to realize the on-site matching between the sensor signal acquisition and the active load of the analog input interface, and effectively solve the problem of collecting active 4- The 20mA current signal conflicts with the power supply of the receiving port of the two-wire current loop power supply loop. This solution adopts high-efficiency loop electricity stealing technology, no independent power supply is required, and it is very convenient to use. Users can perform ADJ correction by adjusting the potentiometer.

Detailed technical information：https://www.sunyuansz.com/uploads/soft/210811/2-210Q1102924.pdf

The application seven of Two-wire signal isolator:Passive low cost, small size two-wire PWM signal to analog signal isolator

ISO D-O1 series (SIP8 Pin package) is transmitter IC that a passive PWM pulse width modulation signal isolation conversion to two-wire 4-20mA. The working mode of the IC is through the current loop feeding mode of the rear stage (output end), receiving the PWM signal output from the previous stage equipment, and outputting the corresponding 4-20mA standard two-wire current signal after isolation and conversion.The PWM pulse width transmitter solution is designed as a SIP8 Pin (single row 8-pin in-line package) small-volume PCB board welding installation method. The IC includes a signal coupling high-speed isolation conversion circuit, a precision reference voltage source switch control circuit, and a low-pass filter. It has the characteristics of high PWM signal conversion accuracy, good linearity, and a wide range of output loop supply voltage (12-36VDC).The highly integrated process structure and new technology isolation measures enable the core devices in the solution to achieve: 3000VDC isolation between signal input and output, and can meet the requirements of industrial-grade wide temperature, humidity, and vibration on-site harsh working environment.

Detailed technical information：https://www.sunyuansz.com/uploads/soft/210811/2-210Q1113501.pdf

The application of two-wire signal isolator : Passive two-wire Pt100/Cu50 thermal resistance temperature measurement signal loop feed signal isolator

ISO Z-W-O1 small size (12-pin single-in-line IC package SIP12 Pin) low-cost passive two-wire 4-20mA loop-fed thermal resistance signal isolation transmitter, mainly used for three-wire, four-wire or two-wire system Acquisition, isolation and transmission of Pt10 / Pt100 / Pt1000 or Cu50/Cu100 temperature sensor signals.The solution is used in the temperature detection of the industrial site, and the temperature signal collected by the thermal resistance sensor can be converted into a standard 4-20mA current signal output with a linear ratio according to the change amount.ISO Z-W-O1 adopts electromagnetic isolation mode and high-efficiency post-feeding invention patent technology, which can realize precise isolation conversion of temperature signal output by thermal resistance sensor to 4-20mA standard signal without independent power supply. The analog input port of the instrument (such as PLC, DCS system, etc.) matches.The IC includes signal modulation and demodulation circuit, signal coupling isolation conversion circuit, high-efficiency DC-DC boost circuit, signal zero point, full scale calibration circuit and Pt100 thermal resistance linearization, long-term compensation, interference suppression circuit, etc. The output circuit has a wide supply voltage range (12-36VDC), high conversion accuracy, and good linearity. The full scale and zero point can be adjusted and calibrated on-site by the user through an external potentiometer.

The application 9 of Two-wire signal isolator：Passive two-wire alternating current (AC) current and voltage signal to 4-20mA analog signal isolator

DIN ISO AC-O1 series AC to DC (AC/DC) passive two-wire signal isolation transmitter is an isolation transformer that can output the DC standard 4-20mA current signal according to the measured AC current and voltage in linear proportion. transmitter.Equipped with the corresponding indicating instrument or sent to the DCS/FCS system directly, the system can measure and control the AC voltage or current.

The output of this module is designed for a two-wire power supply loop with 24VDC and a sampling resistor (two-wire instrument) connected in series.It matches the analog input port of the analog input interface board (host computer), PLC, DCS or other instruments commonly used in the current industrial field.The high-efficiency loop power stealing technology is selected in the scheme design without independent power supply, and the two-wire loop power supply output method can save two power lines, which greatly simplifies the user's system scheme design and reduces the user's wiring cost.

In the design of the scheme, the working power circuit of the indicating instrument, PLC or DCS and other devices in the system is fully used, and the input circuit device of the signal is completely isolated from the output detection control circuit, which improves the reliability and stability of the system operation, and fully guarantees and improves. The safety factor of equipment and staff, so this solution is widely used in the fields of power remote monitoring, power instrumentation, medical equipment, industrial automation and other fields.

Detailed technical information：https://www.sunyuansz.com/uploads/soft/210811/2-210Q1133U6.pdf