402-896-300 DP Transmitter Unit

Module Feature

402-896-300 is a low-range differential pressure smart transmitter designed for non-corrosive air and neutral gas measurement.

It adopts stable capacitive pressure sensing element, with built-in temperature compensation circuit. It supports 4-20mA analog signal superimposed with HART digital communication, local LCD display and zero/span adjustment. It has compact aluminum alloy housing, IP66 protection, reverse wiring and surge protection, and is commonly deployed for air handler, baghouse filter clogging alarm, clean room and fume hood pressure monitoring.

Working principle

High side and low side pressure are introduced to two sides of the sensing diaphragm.

The diaphragm displacement changes capacitance value proportionally with pressure difference. The signal conditioning PCB converts the capacitance variation into standardized 4-20mA current signal, and embeds HART digital data for remote configuration and diagnostic reading.

Onboard components

Capacitive differential sensing cell, signal conditioning PCB, HART communication chip, local LCD display, two pressure port fittings, two-wire terminal block, lightning protection circuit.

LED indicators

Front LEDs indicate loop power status, measurement running state, over-range fault and communication activity.

Hardware self‑diagnosis

Built-in supervision detects sensor drift, loop open, over-pressure and internal electronic failure. Fault codes can be checked on local LCD or read via HART host software.

Programming software

HART configuration tool, used for range setup, damping adjustment, sensor trim and tag management.

Electrical & Process Parameters

Model:402-896-300 Brand:Unconfirmed Device type:Smart differential pressure transmitter Function:Differential pressure measurement and signal transmission for air duct, filter and cleanroom automation monitoring

Mechanical & Structure

Mounting:Wall or pipe bracket mounting Protection class:IP66 Housing:Coated aluminum alloy instrument enclosure

Environmental

Operating temperature:-20℃ ~ +85℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non‑condensing

Certification:CE, HART

Status:Original process instrumentation spare

Installation

Install the unit away from direct airflow and vibration sources.

Connect high/low pressure sampling tubing and two-wire loop cable, set measuring range and damping before commissioning.

Interface

High pressure port, low pressure port, two-wire power and signal terminal block.

Diagnostic

No output signal: Loop power loss, sampling tube blockage or internal circuit damage.

Reading drift: Water condensation inside sampling line, temperature shock or overdue calibration.

HART communication offline: Loop resistance mismatch, cable short circuit or communication chip fault.

Product Brief

402-896-300 differential pressure transmitter, HART two-wire low pressure instrument spare for HVAC and cleanroom pressure monitoring.