Description
ROSEMOUNT
MODEL: 644HAI1Q4
TEMPERATURE TRANSMITTER
P/N.: 00644-7600-0001
OUTPUT: 4-20 MA 10.12
SUPPLY: 12-42.4 VDC SW 1.1.1
SEN 1: PT100_385 4 WIRE
RNG: 32 TO 572 DEG C
HW: 1 SW: 793
644-7511-0001/AA
The Rosemount 644HAI1Q4 is a head-mount temperature transmitter engineered for accurate, reliable temperature measurement in demanding industrial and marine environments. Accepting a PT100 (385) 4-wire RTD input and delivering a standard 4-20mA analogue output, it converts sensor readings into a signal suitable for integration with distributed control systems, PLCs, and monitoring panels. With a measuring range of 32 to 572°C and a supply voltage of 12–42.4 VDC, this transmitter is well-suited to process monitoring applications across marine control systems onboard commercial and industrial vessels. Precise temperature data is critical to the safe and efficient operation of machinery spaces, auxiliary systems, and process plant — making a dependable transmitter an essential component in the overall automation architecture.
Key Features
✓ Analogue 4-20mA output ensures compatibility with a wide range of marine automation controllers, DCS platforms, and monitoring systems without requiring signal conversion.
✓ Accepts PT100 (α=0.00385) 4-wire RTD input with a calibrated measurement range of 32 to 572°C, providing high-accuracy temperature sensing across thermally intensive marine processes.
✓ Wide supply voltage range of 12–42.4 VDC accommodates varying onboard power supply conditions, offering installation flexibility in marine panel and field-mounted configurations.
✓ Head-mount form factor allows direct installation into standard sensor connection heads, simplifying retrofit and replacement without significant modifications to existing wiring or pipework.
✓ Firmware and hardware revision data (HW: 1, SW: 793) support traceability during service, calibration, and system upgrade activities — subject to confirmation of compatibility with specific control system versions.
Marine Applications
✓ Main engine and auxiliary machinery temperature monitoring, including cooling water, lube oil, exhaust gas, and fuel systems where continuous process data is required.
✓ Cargo handling and process control systems aboard tankers, gas carriers, and bulk carriers where precise temperature measurement supports safe cargo operations.
✓ Boiler and steam system instrumentation on vessels with steam propulsion or auxiliary steam generation, where accurate temperature feedback is critical to plant efficiency and safety.
✓ HVAC and refrigeration plant monitoring on passenger vessels, reefer vessels, and offshore units requiring tight temperature control across multiple zones.
✓ Offshore platform and marine process plant instrumentation where 4-20mA field devices are integrated into centralised safety and control systems.
Why Marine Engineers Choose
The Rosemount 644 series is a well-established transmitter platform recognised for measurement stability, straightforward commissioning, and broad compatibility with marine and industrial control architectures. The 4-wire PT100 input configuration minimises lead resistance errors, supporting measurement integrity over longer cable runs typical in shipboard installations — making it a trusted choice for critical temperature loops.
Ideal For
Suitable for commercial cargo vessels, tankers, bulk carriers, offshore support vessels, passenger ships, naval auxiliaries, and marine process plant operators requiring a reliable analogue temperature transmitter for integration into existing or upgraded control systems.
Technical Support & Compliance
Technical assistance is available to support remote troubleshooting, onboard commissioning, calibration verification, and system integration of this transmitter into existing marine control architectures. Retrofit and upgrade guidance can be provided to assist engineers replacing legacy instrumentation or expanding existing monitoring loops — subject to confirmation of system compatibility. To verify suitability for your application, buyers are encouraged to share nameplate photographs, the full part number, relevant loop drawings or instrument data sheets, the control system model and software version, and vessel name or IMO number where applicable. Compatibility and fitment are subject to confirmation based on the information provided.
