Description
ROSEMOUNT
MODEL: 644RAI1A1Q4
P/N: 00644-6412-1005
TEMPERATURE TRANSMITTER
00644-1100-0002
REV.AA
00644-1070-0004
REV.AD
The Rosemount 644RAI1A1Q4 is a head-mounted temperature transmitter designed to convert sensor input signals into reliable, stable process outputs for use within marine control and monitoring systems. Part number 00644-6412-1005 represents a proven instrument in the Rosemount 644 series, widely used across marine and industrial environments where accurate temperature measurement is essential to safe and efficient vessel operation. As a core component within marine control system infrastructure, this transmitter supports continuous process monitoring across machinery spaces, engine rooms, and auxiliary systems where temperature data directly informs operational decisions and alarm management.
Key Features
✓ Head-mounted temperature transmitter designed to interface with RTD or thermocouple sensors, converting temperature signals into a stable process output suitable for marine control and monitoring loops — exact input type and output range subject to confirmation based on configuration.
✓ Built to Rosemount 644 series standards, known for signal stability and sensor diagnostic capability; specific approvals, certifications, and communication protocols applicable to this configuration should be confirmed against nameplate and documentation.
✓ Compatible with a range of distributed control systems, PLCs, and ship automation panels typical of marine machinery monitoring installations; system-level compatibility should be verified against the vessel’s existing control architecture.
✓ Suitable for installation in instrumentation head assemblies within engine rooms and machinery spaces; mounting configuration, environmental ingress protection rating, and area classification suitability are subject to confirmation from technical drawings and vessel records.
✓ Intended as a direct replacement or retrofit transmitter within existing Rosemount 644 series installations; revision references REV.AA and REV.AD are noted and should be cross-checked during procurement to ensure compatibility with the fitted sensor assembly and control system version.
Marine Applications
✓ Main engine and auxiliary engine temperature monitoring systems aboard cargo vessels, tankers, and bulk carriers, where continuous measurement supports machinery protection and performance optimisation.
✓ Boiler and steam system temperature instrumentation loops on vessels with steam propulsion or steam-assisted cargo handling systems.
✓ HVAC and refrigeration plant monitoring aboard passenger vessels, reefer ships, and offshore support vessels requiring precise temperature control within defined operational bands.
✓ Fuel oil conditioning and treatment systems where accurate temperature data is required to maintain viscosity targets and protect injection equipment.
✓ Offshore platforms, FPSOs, and naval auxiliaries utilising centralised process control systems that depend on reliable field transmitter performance across a wide range of ambient and process conditions.
Why Marine Engineers Choose
The Rosemount 644 series has established a strong reputation in marine and offshore environments for measurement reliability, ease of configuration, and compatibility with widely deployed control infrastructure. Engineers working with Rosemount-equipped vessels often specify the 644 series transmitter as a like-for-like replacement to maintain calibration continuity and minimise re-commissioning time during scheduled maintenance or unplanned repairs.
Ideal For
Cargo ships, bulk carriers, tankers, container vessels, offshore support vessels, FPSOs, passenger ships, naval auxiliaries, and any vessel class operating Rosemount-based temperature measurement and marine control system infrastructure.
Technical Support & Compliance
Technical support is available to assist with remote troubleshooting, onboard installation guidance, commissioning, calibration verification, and integration into existing marine control systems — all subject to confirmation of the specific vessel configuration. Retrofit and upgrade suitability, as well as compatibility with existing sensor assemblies and control panels, can be assessed prior to despatch. To confirm suitability and avoid procurement errors, buyers are advised to share nameplate photographs, full part numbers, revision references, system model and software version details, applicable technical drawings, and vessel name or IMO number where available. All compatibility and compliance assessments are subject to confirmation based on the information provided.
