Description
FOXBORO RH926HT
Technical Specifications
- Product type: RTD temperature transmitter
- Supported sensor: Pt100 platinum resistance thermometer
- Signal output: 4 to 20mA two wire
- Power supply: DC12V to DC42V
- Measuring range: Configurable within Pt100 working range
- Accuracy: ±0.1% full scale
- Sensor connection: 2 wire, 3 wire, 4 wire RTD
- Operating temperature: -40 °C to +85 °C
- Storage temperature: -50 °C to +100 °C
- Humidity: 0% to 95%, non-condensing
- Protection rating: IP67
- Mounting: Head mount inside temperature sensor housing
- Certification: CE, ATEX intrinsic safety certification
Functional Features
- Support Pt100 RTD multiple wiring modes
- 4 to 20mA two wire loop powered design
- Wide DC supply voltage range
- High accuracy temperature conversion
- Linearization compensation for platinum sensor curve
- Built-in overvoltage and reverse polarity protection
- Intrinsically safe design for hazardous area installation
- Remote configuration via HART communication
- Long term signal stability
- Resistance to plant vibration and dust
Application Scenarios
- Petrochemical reactor temperature monitoring
- Refinery pipeline temperature measurement
- Power plant boiler and steam pipe temperature
- Chemical batch process temperature control
- Food and pharmaceutical process temperature monitoring
Materials and Construction
- Housing: Die cast aluminum alloy
- Cover: Aluminum alloy with corrosion resistant coating
- PCB: FR4 board with conformal coating
- Terminal block: Glass filled nylon insulated terminals
- Seal: EPDM rubber sealing ring
- Electronic components: Industrial grade resistors and capacitors
Structural Features
- Compact cylindrical head mount structure
- Internal terminal compartment isolated from electronics compartment
- Threaded cover for easy access during wiring
- Two cable entry ports for field wiring
- Internal signal conditioning circuit board fixed inside housing
- Fully sealed enclosure for dust and moisture protection
Working Principle Pt100 resistance changes with measured medium temperature. The transmitter circuit excites the RTD sensor and samples resistance value. The microprocessor performs linearization calculation and temperature compensation, then converts temperature value into 4 to 20mA loop current signal. The current signal travels through two wire loop to the control system input card. HART protocol superimposed on current signal supports remote parameter setting and diagnostic reading.
Installation Requirements
- Install transmitter inside temperature sensor connection head
- Use shielded twisted pair cable for signal loop
- Maintain proper cable separation from high voltage power cables
- DC loop power supply connected with correct polarity
- Set sensor type and measuring range via HART communicator after installation
- Tighten housing cover and cable glands to preserve IP67 rating
- Keep ambient temperature within -40 °C to +85 °C
Precautions
- Verify RTD wiring connection type matches transmitter configuration
- Do not exceed maximum loop resistance specified for 4-20mA circuit
- Avoid strong electromagnetic interference sources nearby
- Confirm intrinsic safety certification for hazardous area installation
- Store spare transmitters in dry environment
- Calibrate temperature measurement at regular maintenance intervals
- Prevent mechanical impact on aluminum housing during installation
