Product Description
Rosemount 644 Temperature Transmitter Comprehensive Product Introduction
1. Technical Specifications and Performance
The Rosemount 644 Series is a high-precision temperature transmitter designed for industrial process control, offering exceptional reliability and accuracy in demanding environments. Key specifications include:
Input Compatibility: Supports a wide range of sensors, including RTDs (2-, 3-, or 4-wire configurations), thermocouples (Type K, J, E, etc.), millivolt (mV), and resistance (Ω) signals
Accuracy: Achieves ±0.15°C (±0.27°F) for Pt100 RTDs, ensuring precise temperature measurements critical for process integrity. Environmental temperature compensation further enhances performance
Stability: Two-year stability guarantee minimizes calibration frequency and maintenance costs .
Output Options:
4-20 mA HART (HART 5, HART 7)
Foundation Fieldbus or Profibus PA protocols
Customizable alarms and PID control capabilities for field-level automation
Environmental Robustness:
Vibration resistance: Certified for 3g at 60-500 Hz
Operating voltage: 12-42.2V DC (HART) or 9-32V DC (Fieldbus)
Conforms to NAMUR NE 21 standards for electromagnetic compatibility (EMC)
Detailed Photos
2. Hardware Design and Installation Flexibility
The 644 Series caters to diverse installation requirements with modular hardware options:
Mounting Configurations:
DIN A-Type Head-Mounted Transmitter: Direct installation on sensor heads for compact setups.
Rail-Mounted Transmitter: DIN rail compatibility for control panel integration .
Enclosure Materials: Aluminum or stainless steel housings provide corrosion resistance in harsh industrial environments (e.g., chemical processing, offshore platforms) .
Terminal Design: Simplified electrical connections with screw-clamp terminals, reducing installation time .
Display Options: Integrated LCD shows primary variables (PV), sensor status, diagnostics, and configuration parameters. The display supports unit customization (°C/°F) and damping adjustments
3. Advanced Software and Diagnostic Capabilities
The 644 Series leverages smart technology for operational efficiency and predictive maintenance:
Transmitter-Sensor Matching (TSM): Uses the Callendar-Van Dusen equation to optimize sensor-transmitter pairing, improving measurement accuracy by up to 75% .
Diagnostics:
Sensor Health Monitoring: Detects open-circuit, short-circuit, and intermittent sensor faults with configurable delay functions to prevent false alarms .
Terminal Temperature Compensation: Validates installation temperature to ensure optimal performance .
PlantWeb Alerts: Integrates with Emerson's PlantWeb ecosystem for real-time process visibility and alerts [[4][14]].
HART Communication:
Menu structure includes Device Status, Guided Setup, Sensor Configuration, Analog Output Calibration, and Security Settings (see Table 1)
Compatibility with HART 475 handheld configurators simplifies field calibration and troubleshooting
Product Parameters
| Menu Level |
Functionality |
| Device Status |
Reports PV, sensor health, output current, and firmware version |
| Sensor Setup |
Configures sensor type, damping (0-100 sec), units, and TSM |
| Analog Output |
Sets upper/lower range values (URV/LRV), alarm thresholds, and failsafe actions |
| Diagnostics |
Enables sensor limit checks, trend analysis, and maintenance alerts |
| Security |
Configures write-protection and access levels |
4. Application-Specific Solutions
The 644 Series addresses niche industrial challenges through tailored features:
Process Criticality: PID control blocks enable in-field loop control for rapid response scenarios (e.g., reactor temperature stabilization)
Safety Compliance: FISCO-certified Fieldbus installations for hazardous areas
Energy Efficiency: Environmental temperature compensation reduces measurement drift in fluctuating ambient conditions (e.g., outdoor LNG terminals) .
Lifecycle Management: Emerson's "Assemble-to-Sensor" program offers pre-configured transmitter-sensor assemblies, reducing commissioning time .
5. Installation and Maintenance Best Practices
Configuration Workflow:
Isolate the loop and set to manual mode.
Use HART configurators (e.g., 475) or Emerson AMS Suite for setup.
Verify sensor limits, damping, and alarm thresholds
Surge Protection: Integrated transient voltage suppression (TVS) protects against lightning and power surges
Calibration: Leverage 18-bit analog-to-digital conversion for reduced drift; stability allows 24-month calibration intervals [[4][14]].
Fault Diagnosis: Utilize Trends and Maintenance menus in HART to analyze historical data and predict failures
Conclusion
The Rosemount 644 Series redefines temperature measurement with its fusion of precision engineering, smart diagnostics, and installation versatility. Its compliance with global standards (NAMUR, FISCO) and seamless integration into digital ecosystems (PlantWeb, Fieldbus) make it indispensable for industries prioritizing process safety and operational excellence. As part of Emerson's holistic temperature solutions, the 644 transmitter ensures long-term reliability while minimizing lifecycle costs-proving essential for modern industrial automation.
Company Profile
KeRui (weifang) Automation Equipment Co., Ltd. specializes in industrial automation instrument development, production and sales,technical services, and supporting equipment supply of specialized companies. The main products are flow meters, level meters,temperature meters, pressure meters, electrical meters, thermal intelligent meters, programmable controllers (PLC), DCS distributed control systems, and eight series of more than 1,000 specifications. Its products and technologies are widely used in electric power, metallurgy, petrochemicals, environmental protection, plastics, food, printing, tobacco, textile, dyeing, and other fields.
Packaging & Shipping
The packaging and transportation of instrumentation in global trade hinges on a synergy of advanced materials, rigorous testing, regulatory compliance, and smart logistics. By adopting hybrid structural designs, leveraging real-time monitoring technologies, and prioritizing sustainability, exporters can ensure the safe, efficient, and cost-effective delivery of precision instruments. Continuous innovation in materials science and IoT integration will further redefine industry standards, enhancing resilience in an increasingly interconnected market.
FAQ
Q: How long will you give me the reply?
A: We will reply to you as soon as we see the information.
Q: What is the delivery time?
A: Our delivery time is within 3-7 days after we get your payment;
for large qty mass orders, the time should be confirmed again for you.
Q: How about your package?
A: Do not worry about the package, we have rich experience in packing, and all our package is wooden case package.
Q: How about the payment terms?
A: You can choose T/T.
Q: Do you provide samples?
A: Yes, we have materials in stock to help you to get the samples as soon as we can.
Q: What is the MOQ?
A:1PC.
Q: Can I get a lower price if I order large quantities?
A: Yes, cheaper prices with more bigger size orders.
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