Honeywell STF724 Flange Mount Transmitter Unit

Module Feature

STF724-M1AC4A-15D-E-AH0-11S-A-00A0-00-0000 belongs to Honeywell SmartLine STF700 series, a direct flange-mounted pressure transmitter with integral diaphragm seal. It is designed for liquid level measurement of corrosive, viscous or solids-containing media that cannot directly contact the sensor cell. It features temperature and static pressure compensation, high turndown and high accuracy performance. Local LCD display and push-button zero/span adjustment are available. Two-wire loop power, 4-20mA analog signal superimposed with HART7 digital communication. It supports SIL2 capability, dual seal design conforming to ISA 12.27.0. Widely used in chemical tanks, slurry vessels and heavy oil storage tank level monitoring.

Working principle

Process pressure transfers through the flange diaphragm and fill fluid to the internal capacitive sensing cell. The sensor converts pressure variation into capacitance change. The transmitter electronics convert this value to standard 4-20mA output and embed HART digital data. Internal algorithm compensates errors caused by ambient temperature and static pressure. Level value, sensor status and diagnostic codes can be read by HART communicator or DCS host.

Onboard components

Capacitive sensing module, filled capillary / integral diaphragm seal, 316L or Hastelloy diaphragm, signal conditioning PCB, HART communication chip, LCD display, local push buttons, aluminum transmitter housing, process flange assembly.

LED indicators

No dedicated LED indicators. Process value and fault information are shown on the LCD display.

Hardware self-diagnosis

Sensor drift detection, overpressure detection, fill fluid leakage alarm, loop current fault, memory checksum test, diagnostic codes accessible via HART.

Programming software

Honeywell Field Device Manager, HART communicator, used for range configuration, level setup, sensor trim and firmware maintenance.

Electrical & Process Parameters

Model:STF724-M1AC4A-15D-E-AH0-11S-A-00A0-00-0000 Brand:Honeywell Device type:Flange Mount Level Transmitter Power supply:10.5~42VDC loop powered Signal:4-20mA + HART7 Safety:SIL2 capable Accuracy:0.065% FS Protection:IP66 / IP67, explosion-proof available

Mechanical & Structure

Mounting:Direct flange mount on vessel nozzle Protection class:IP66 / IP67 Housing:Cast aluminum head, process flange with sealed diaphragm

Environmental

Operating temperature:-40℃ ~ +85℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non-condensing Certification:CE, UL, FM, SIL2 compliant Status: Honeywell original SmartLine STF700 flange transmitter

Installation

Isolate vessel pressure before installation. Mount Honeywell STF724 transmitter onto tank nozzle flange, tighten bolts following torque specification. Wire two-wire signal cable to control system. Complete zero trim after installation and verify HART communication and level reading.

Interface

Process flange diaphragm, 1/2"NPT electrical entry, HART communication interface.

Diagnostic

Fixed 4mA output: diaphragm damage or fill fluid loss. Reading drifting: temperature fluctuation without proper compensation or seal contamination. HART no response: reversed loop polarity or insufficient loop resistance.

Product Brief

Honeywell STF724-M1AC4A-15D-E-AH0-11S-A-00A0-00-0000 SmartLine STF700 flange mount level transmitter, integral diaphragm seal, HART7, SIL2 capable, for tank liquid level measurement of difficult process media.