SY 4-20mA Two-Wire Non-Isolated Loop Signal Conditioner IC

Device features:

1. Protect the control loop of the upper stage of the host computer.

2. Reduce the impact of environmental noise on the test circuit, and can overcome inverter noise and various high and low frequency pulsation interference.

3. It suppresses the interference of circulating currents in public ground wires and pulses of frequency converters, solenoid valves, thyristors, etc. to equipment. It also has the function of limiting voltage and current for lower-level equipment. It is a faithful protection for transmitters, instruments, frequency converters, solenoid valves, PLC/DCS input and output, and communication interfaces.

The DIN35 series standard 35mm guide rail card holder structure is easy to install and can effectively isolate: the potential difference between signal input, signal output, power supply and earth.

Product Advantage

1.Zero External Power Required

Fully loop-powered—draws operating energy from the 7.5–32VDC signal loop itself. No auxiliary supply, no DC/DC converter, no extra wiring. Simplifies field installations dramatically: just two wires carry both power and the conditioned 4-20mA signal to the PLC or DCS analog input card.

2.0.05% Accuracy with 2KHz Bandwidth

Factory-trimmed to 0.05% FS with gain of 1 mA/mA and non-linearity below 0.1%. 2KHz small-signal bandwidth handles dynamic process signals. ±30–75 ppm/°C temperature drift and 5mV output ripple. 50Ω input impedance minimizes loading on source loops; 750Ω load driving at 24VDC.

3.Dual-Mode: Current or Voltage Input

SY 4-20mA-P accepts 0–40mA current input. SY V-4-20mA-P variant accepts user-defined voltage (e.g. 0–5V, 1–5V) via external resistor network. Both output a clean 4-20mA loop signal. A single 2KΩ multi-turn potentiometer on the ADJ pin calibrates full-scale gain.

4.Multi-Channel DIN-Rail Options

DIN3 version embeds a single channel in a 12.5mm-thin DIN35 housing with screw terminals and field-accessible zero/span trim. DIN 1X1/2X2/3X3 versions stack 2–3 channels in one enclosure with built-in surge suppression—completely passive, no power supply needed for any channel.

Technical Parameters

Product Uses

1.PLC/DCS analog signal field acquisition: The module acquires 4-20mA signals from field sensors without auxiliary power, drawing energy directly from the loop (7.5~32V wide range). SIP7 package enables compact board-level integration. Only requires one 2KΩ potentiometer for calibration.

2.Sensor 4-20mA signal conditioning and long-distance transmission: The module regenerates 4-20mA signals for long cable runs, compensating for voltage drops and EMI. Non-linearity <0.1% FSR ensures signal integrity. Load capacity 750Ω@24VDC drives standard PLC analog input ports.

3.Voltage-to-current (V/I) signal conversion: The module converts voltage inputs (0-Vin or 1-5V) to 4-20mA current outputs via external resistors. Useful for integrating voltage-output sensors with current-loop接收 PLC/DCS systems. Gain=1mA/mA maintains signal fidelity.

4.Potentiometer/displacement signal acquisition: The module converts potentiometer resistance changes (0~5KΩ) to 4-20mA outputs for angle, position, or displacement measurement. Adjustable zero (ZA) and span (ADJ) via external trimpots. Ideal for valve position feedback and electronic scale applications.

5.Industrial instrumentation signal matching: The module matches sensor output signals to analog input interfaces of various instruments. Low 50Ω input impedance minimizes sensor loading. -45°C to +85°C operating range suits harsh industrial environments.

6.DIN35 rail-mount multi-channel deployment: The DIN3 version (12.5mm thick) enables dense rail-mount installation. Multi-channel versions (DIN1X1/2X2/3X3) support 1-3 channel I/I conditioning without auxiliary power. Internal surge suppression adds reliability.

7.Industrial process data acquisition and monitoring: The module serves as a low-cost front-end conditioner for process monitoring systems, acquiring temperature, pressure, flow, and level signals. 2KHz bandwidth supports dynamic measurement. Output short-circuit protected for field reliability.