Emerson Rosemount 644 Temperature Transmitter
Product Introduction
The Rosemount 644 temperature transmitter is designed for use in control applications where the loss of the temperature points may be detrimental. These highly accurate Rosemount 644 temperature transmitters are available in a variety of mounting styles, field housings, and communication protocols to meet your demanding installation requirements.
Each Rosemount 644 temperature transmitter is a 2-wire design providing either a 4-20 mA/HART or a completely digital FOUNDATION fieldbus ouput. Each unit can be configured for a variety of sensor inputs: RTD, themocouple, millivolt, or ohm. The advanced Rosemount 644 temperature transmitter powers PlantWeb ® by communicating important temperature diagnostics and PlantWeb alerts to ensure process health and enable economical single-sensor architecture.
Entering the temperature-resistance profile specific to the RTD sensor into the Rosemount 644 temperature transmitter results in transmitter-sensor matching. This eliminates the sensor interchangeability error, which can improve accuracy by up to 75%. The integral LCD display provides local indication of temperature measurement and diagnostics for immediate and accurate verification or process conditions.
Meeting the NAMUR NE 21 recommendations, the Rosemount 644 temperature transmitter ensures top transmitter performance in harsh EMC environments. In addition, the Rosemount 644 HART transmitter meets NAMUR NE 43 and NE 89 recommendations.
The Rosemount 644 temperature transmitter offers great mounting flexibility. The DIN A style head mount transmitters fits a variety of housings for remote transmitter mounting and can be integral or remote mounted to a sensor. The compact rail mount style is great for DIN rail mounting in the tight spaces of a crowded control room.
Quick Detail
Ability to accept universal sensor inputs (RTDs, T/C, mV and ohm)
Transmitter-Sensor Matching improves system accuracy up to 75%
Ambient Temperature Compensation functionality
Variety of enclosure options for Head Mount including polished stainless steel housings for biotechnology, pharmaceutical and other sanitary applications
Available as an installation-ready Complete Point Solution that includes a variety of sensors, thermowells and enclosures
Emerson Rosemount 644 Temperature Transmitter
Brand | Rosemount |
Model | 644 |
Output | 4~20mA Hart,Profibus,FF |
Input | Thermal resistance: PT100 0~150°C |
Accuracy | Thermal resistance: ±0.2%FS |
Cold junction compensation | 0~50°C±1°C |
Temperature drift | ±0.2%/°C |
Adjustment method | Potentiometer |
Power | 24VDC±10% |
Ambient Temperature | -20~80°C |
Load capacity | 0~500Ω |
Ambient Humidity | <85%RH |
Accuracy | ±0.10°C (±0.18°F) |
Stability | 5-year stability |
Warranty | 12/18 months, 3-year or 5-year limited warranty options |
Input | Dual and single sensor capability with universal sensor inputs (RTD, T/C, mV, ohms) |
Output Signal | 4-20 mA /HART® protocol, FOUNDATION™ fieldbus protocol, PROFIBUS® PA protocol |
Housing | Field mount, DIN A head mount or rail mount |
Display/Interface | LCD Display or LCD Display with Local Operator Interface (LOI) |
Diagnostics | Basic diagnostics, Hot Backup™ capability, sensor drift alert, thermocouple degradation, min/max tracking |
Calibration Options | Transmitter-sensor matching (Callendar-Van Dusen constants), 5-point calibration |
Certifications/Approvals | SIL 2/3 certified to IEC 61508 by an independent 3rd party, hazardous location, marine type, see full specs for complete list of certifications |
Features
• | Extremely versatile temperature transmitter available in HART®, FOUNDATION™ Fieldbus or PROFIBUS® protocols |
• | Diverse mounting configurations including head, field or rail mount with many enclosure options |
• | LOI option eliminates the need for special configuration tools (i.e. field communicator) for ease-of-use |
• | Transmitter-sensor matching with Callendar-Van Dusen constants reduces total measurement error |
• | Hot Backup™ capability and sensor drift alert with dual sensors ensure measurement integrity |
• | Thermocouple degradation diagnostic monitors thermocouple health to detect degradation before failure |
• | Minimum and maximum temperature tracking observes temperature extremes for easy troubleshooting |
• | Device dashboards provide easy interface for simplified device configuration and diagnostic troubleshooting |