Temperature Transmitters

Temperature Transmitters

Temperature transmitters condition RTD or thermocouple inputs and convert them into standardized analog or digital output signals for control systems and asset monitoring platforms. This standardization simplifies downstream design by enabling consistent input cards, barriers, and wiring practices between the transmitter and the automation system, even when primary sensors differ. The transmitter becomes the point where sensor behavior, linearization, diagnostics, and communications are consolidated into a repeatable interface.

Three primary transmitter form factors support different installation philosophies. DIN rail devices suit panel and cabinet integration, head transmitters mount directly in thermometer heads to minimize field wiring, and field transmitters are installed in the process area for robust local connection and service access. Selecting the appropriate housing style aligns environmental exposure, wiring topology, and maintenance practices with the measurement point’s criticality.

Communication capabilities span legacy and modern digital architectures. Analog 4–20 mA remains common, while HART extends the analog signal with an overlay of digital information for configuration and additional variables. Fully digital protocols such as PROFIBUS, PROFINET, and Foundation Fieldbus can transmit measured value plus additional information purely digitally. For commissioning and maintenance efficiency, some transmitter designs support wireless Bluetooth® parameterization in the field.

Transmitters can improve accuracy, safety, and diagnostic coverage at the measuring point. Accuracy gains come from stable output signals, calibrated sensor/electronics behavior, and sensor‑transmitter matching (including Callendar–Van Dusen linearization), while galvanic isolation helps reduce measurement errors. Safety enhancements include suitability for hazardous areas, SIL-capable variants, extended diagnostics such as corrosion detection, and dual-channel inputs for sensor backup and drift detection.

Usability features focus on faster commissioning and clearer lifecycle visibility. Parameterization and monitoring can be performed via Bluetooth or digital communications, and on-site indication can be supported through integrated or pluggable displays. Installation is streamlined through wiring-friendly features such as push-in terminals, enabling consistent build quality across large transmitter populations. These traits support modernization projects and measurement-point standardization where repeatability and diagnostic depth are as important as the measured value itself.

George E. Booth Co., an exclusive authorized representative of sales and service for Endress+Hauser.