EOM-O2-MINI-90-MODRTU-V1 Mini O2 Gas Transmitter Unit

Module Feature

EOM-O2-MINI-90-MODRTU-V1 is a compact oxygen concentration transmitter. It adopts electrochemical oxygen sensor core, supports 0~90%VOL oxygen measurement range.

Communication interface is RS485 with standard MODBUS RTU protocol, easy to connect with PLC, DCS and industrial acquisition host. The circuit has temperature compensation function to reduce measurement drift caused by ambient temperature change. Small footprint design, suitable for installation inside cabinets, confined space monitoring boxes and biogas analysis assemblies.

Working principle

Oxygen molecules diffuse through the sensor membrane into the electrochemical cell. The chemical reaction generates weak current signal proportional to oxygen concentration.

The acquisition board samples and temperature compensates the raw signal, converts it into digital value, and uploads oxygen data, sensor status and fault flags to upper controller via MODBUS RTU bus.

Onboard components

Electrochemical O2 sensor, signal conditioning circuit, temperature sampling chip, RS485 communication circuit, MCU main control board, terminal wiring block.

LED indicators

Front LED indicators for power supply, bus communication and sensor fault status.

Hardware self‑diagnosis

Self-check covers power abnormality, sensor failure, signal out of range and communication timeout. Fault information can be read through MODBUS register.

Programming software

Support MODBUS polling configuration software for station address modification, baud rate setting and calibration operation.

Electrical & Process Parameters

Model:EOM-O2-MINI-90-MODRTU-V1 Brand:EOM Device type:Oxygen Transmitter Measuring range:0~90%VOL Sensor type:Electrochemical Communication:RS485 MODBUS RTU Supply voltage:12~24V DC Function:Online oxygen concentration monitoring for industrial gas environment

Mechanical & Structure

Mounting:Wall or DIN rail mounting Protection class:IP30 Housing:Engineering plastic compact housing

Environmental

Operating temperature:-20℃ ~ +50℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:10~90%RH non‑condensing Certification:CE compliant Status:EOM original gas transmitter spare

Installation

Fix the transmitter on DIN rail or mounting bracket. Wire 12~24V DC power and RS485 bus cable, follow A/B polarity requirement.

Set MODBUS station address and baud rate before putting into service. Avoid installation location with high dust, corrosive gas and direct air blast. Calibrate regularly with standard oxygen gas.

Interface

Power terminals, RS485 A/B communication terminals.

Diagnostic

No MODBUS data: Wrong A/B wiring, inconsistent baud rate or power loss.

Reading drift: Need calibration, sensor aging or temperature shock.

Fault alarm: Sensor end-of-life, blocked air inlet or internal circuit damage.

Product Brief

EOM-O2-MINI-90-MODRTU-V1 mini oxygen transmitter, 0~90%VOL, electrochemical sensor, RS485 MODBUS RTU, used for biogas, confined space and industrial atmosphere oxygen online monitoring.