Overview
Rosemount™ 644 Temperature Transmitter
Engineered for versatility, the Rosemount 644 Temperature Transmitter is available with HART™, FOUNDATION™ Fieldbus or PROFIBUS™ protocols in head, field or rail mount styles and a variety of enclosure options. By adding a Local Operator Interface (LOI), you
can update your transmitter configuration in the field without tools. For diverse application requirements, this transmitter includes diagnostic capabilities, such as Hot Backup™ capability, sensor drift alert and thermocouple degradation.
can update your transmitter configuration in the field without tools. For diverse application requirements, this transmitter includes diagnostic capabilities, such as Hot Backup™ capability, sensor drift alert and thermocouple degradation.
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
* 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
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Specification
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item
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value
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Warranty
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1 Year
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Customized support
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OEM, ODM, OBM
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Place of Origin
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United States
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Brand Name
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EMERSON/ROSEMOUNT
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Model Number
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644 Temperature Transmitter
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Environmental conditions
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Ambient operating temperature range
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Standard: -50 to +85 °C SIL: -40 to +80 °C
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Storage temperature
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-50 to +85 °C
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Calibration temperature
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23...25 °C
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Humidity
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< 99% RH (non-cond.)
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Protection degree
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IP20
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Mechanical specifications
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Dimensions (H x W x D)
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109 x 23.5 x 104 mm
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Weight, single input / dual input
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150 g/160 g
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Maximum wire size
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0.13...2.08 mm2 /AWG 26...14 stranded wire
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Screw terminal torque
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0.5 Nm
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Vibration: IEC 60068-2-6
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2...25 Hz: ±1.6 mm ■ 25...100 Hz: ±4 g
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Common specifications
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Supply voltage, DC
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Rosemount 644R Ordinary Location: 7.5(1)...48(2)VDC ■ Rosemount 644R Hazardous Approval: 7.5(1)...30(2)VDC
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Additional minimum supply voltage when using test terminals
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0.8 V
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Maximum internal power dissipation
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≤ 850 mW per channel
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Minimum load resistance at > 37 V supply
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(Supply voltage – 37)/23 mA
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Isolation voltage, test/operation
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Rosemount 644R Ordinary Location: 2.5 kVAC/55 VAC ■ Rosemount 644R Hazardous Approval: 2.5 kVAC/42 VAC
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Polarity protection
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All inputs and outputs
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Write protection
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Jumper or software
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Warm-up time
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< 5 minutes
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Start-up time
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< 2.75 seconds
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Programming
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HART® protocol
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Signal/noise ratio
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> 60 dB
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Long-term stability, better than
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±0.05% of span/year ■ ±0.18% of span/5 years
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Response time
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70 ms
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Programmable damping
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0-60 s
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Signal dynamics, input
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24 bit
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Signal dynamics, output
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18 bit
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Effect of supply voltage variation
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< 0.005% of span/VDC
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Accuracy example
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When using a Pt 100 (α = 0.00385) sensor input with a 0-100 °C span: ■ Digital accuracy = ± 0.15 °C ■ D/A accuracy = ± 0.03% of
100 °C or ± 0.03 °C ■ Total accuracy = ± 0.18 °C |
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Worldwide Shipping
We are proud to offer worldwide shipping to meet your needs, no matter where you are located.
How We Ship
We normally ship via DHL, UPS, or FedEx for fast and trackable delivery.
Flexible Shipping Options
Depending on your order size and timeline, we also support Air Freight and Sea Freight options.
Trade Terms
We can arrange shipments under DAP (Delivered at Place) or DDP (Delivered Duty Paid). Just let us know your preference.
Why Choose Us
With years of experience and long-term cooperation with reliable freight forwarders, we ensure competitive rates and smooth customs clearance.
