ISO AD02-04 Series 2/4-Channel Isolated Analog Input Module with RS485 Output

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. Independent Isolation for Multi-Point Measurement

Each analog input channel provides a rated 3,000 VDC isolation barrier from the other channels and the communication/output section. This architecture separates channel ground domains, helping reduce ground-loop currents when sensors operate at different electrical potentials. It supports distributed measurement applications where a shared input ground would complicate wiring or introduce interference.

2. High-Resolution Acquisition for Current and Voltage Signals

A 24-bit sigma-delta ADC provides a specified measurement accuracy better than 0.05%. Listed characteristics include ±15 ppm/°C temperature drift and 120 dB common-mode rejection under the stated test conditions.

Available input options include 4–20 mA, 0–10 V, ±100 mV and 0–75 mV signals. The stated operating temperature range is −45°C to +80°C; accuracy and drift should be interpreted according to the applicable specification conditions.

3. Serial Communication with Selectable Protocols

RS-485 and RS-232 interfaces support integration with compatible controllers and supervisory systems. Users can select ASCII communication or Modbus RTU to suit the host application.

The ASCII command set offers ADAM-compatible instructions, while programmable addresses and baud rates from 300 to 38,400 bps provide configuration flexibility. Existing installations should be checked for command and wiring compatibility before replacement. Communication-line protection includes a stated ±15 kV ESD rating.

4. Wide Supply Range and Compact Installation

The module accepts an 8–50 VDC supply and includes reverse-polarity and overvoltage protection. Power consumption below 1 W limits its contribution to cabinet power demand and heat generation.

The 123 × 70 × 30 mm enclosure supports DIN-rail or desktop installation. Internal transient suppression and digital filtering help reduce the effects of surge pulses and power-frequency interference in industrial measurement circuits.

5. Retained Configuration with Software Calibration Access

Factory calibration supports initial deployment, while non-volatile EEPROM retains settings such as address, baud rate, data format and checksum configuration after power is removed.

Software commands provide access to offset and gain recalibration when required by the application’s maintenance or accuracy requirements. Individual channels can also be enabled or disabled, allowing the acquisition configuration to match the connected sensors.

Technical Parameters

Product Uses

1.Industrial multi-point monitoring via RS-485: The module acquires analog signals from distributed sensors (pressure, temperature, flow) and transmits data to a central host via RS-485 bus. Channel-to-channel 3000VDC isolation prevents cross-interference. Supports up to 256 modules per bus with 1200m communication distance.

2.PLC/DCS analog integration via Modbus RTU: The module serves as remote I/O expansion, converting field signals (4-20mA, 0-10V) to digital data via Modbus RTU. ADAM-compatible commands enable seamless integration. 24-bit ADC and 0.05% accuracy exceed typical PLC analog card specs. Parameters stored in non-volatile EEPROM.

3.Smart building automation monitoring: The module monitors HVAC pressure, water tank level, air quality, and access control signals in intelligent buildings. Channel isolation prevents fault propagation between zones. Wide -45°C to +80°C range suits rooftop and underground installations. Dual RS-232/RS-485 interfaces offer flexible configuration and networking.

4.Power substation remote data acquisition: The module acquires busbar voltage, transformer current, and battery signals in substations. 3000VDC isolation and 3KV impulse withstand provide required safety barriers. ±15KV ESD protection ensures reliable RS-485 communication. 120dB CMR rejects 50/60Hz power frequency interference on long cable runs.

5.Medical instrument multi-channel acquisition: The module acquires signals from blood analyzers, centrifuge sensors, and biopotential circuits. 24-bit ADC provides medical-grade precision. Channel isolation prevents cross-contamination of biomedical signals. Support for bipolar inputs (±5V, ±10V, ±20mA) suits bidirectional physiological measurements.

6.Oil and gas pipeline remote monitoring: The module acquires pressure, temperature, and flow signals at remote pipeline stations and transmits via RS-485 to local RTUs. Wide 8-50VDC power suits solar-powered stations. -45°C operation supports Arctic installations. 100ms response time enables near real-time leak detection.