644 Head and Rail Mount Temperature Transmitters

Rosemount 644 Head and Rail Mount Temperature Transmitters

The Rosemount 644 transmitter is for the temperature measurement. It offers a flexible and reliable solution to any temperature measurement. As aaccurate transmitter that comes in either Hart and FOUNDATION Fieldbus communications protocols, and a head mount or rail mount configurations, the Rosemount 644 is designed to meet your most demanding applications. These highly accurate 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 Foundation Fieldbus output.

Feature

1. Inputs: User-selectable; sensor terminals rated to 42.4Vdc.
2. Output: Single 2wired device with a completely digital output with FOUNDATION fieldbus communication (ITK 5.1 compliant).
3. Isolation:Input/output isolation tested to 500Vdc/acrms (707Vdc) at 50/60 Hz

Local Display

The optional fivedigit integral LCD Display includes a floating or fixed decimalpoint. It can also display engineering units (°F, °C, R, K, , and millivolts), milliampere, and percent of span. The display can be configured to alternate between selected display options. Display settings are preconfigured at the factory according to the standard transmitter configuration. They can be reconfigured in the field using FOUNDATION fieldbus communications.

Humidity Limits: 0–99% relative humidity

Update Time: 0.5seconds

Accuracy : FOUNDATION fieldbus: ±0.15 °C

Housing and Standard Meter Cover: 316 SST

Mounting

The 644R attaches directly to a wall or a DIN rail. The 644H installs in a connection head or universal head mounted directly on a sensor assembly, apart from a sensor assembly using a universal head, or to a DIN rail using an optional mounting clip.

Power Supply Effect: Less than ±0.005% of span per voltStability RTDs and thermocouples have a stability of ±0.15% of output reading or 0.15 °C (whichever is greater) for 24
months.

Self Calibration:

The analog-to-digital measurement circuitry automatically self calibrates for each temperature update by comparing the dynamic measurement to extremely stableand accurate internal reference elements

Vibration Effect: The 644 is tested to the following specifications with no effect on performance perIEC 60770-1, 1999.