Thermistor temperature transmitters have strong environmental adaptability and anti-interference ability. By using input protection circuits, electromagnetic shielding, and signal isolation technologies, effective suppression of electromagnetic interference, radio frequency interference, and grounding loops is achieved, ensuring stable measurement signals can still be obtained in industrial sites with strong electromagnetic interference.

The internal architecture of a thermistor temperature transmitter is a precise signal processing system, and its typical structure can be divided into three functional modules:Input bridge circuit, signal amplification and processing circuit, and output conversion circuitThese modules work together to convert the small resistance changes of thermal resistors into standard industrial signal outputs.

Input bridgeIt is the front-end circuit of the transmitter. When the temperature changes and the resistance value of the thermal resistor changes, the bridge loses balance and generates an unbalanced voltage signal proportional to the temperature change. This signal is usually very weak (at the millivolt level) and requires amplification and processing by subsequent circuits.

Signal processing sectionIt is the core of the transmitter, including multi-stage amplification circuit, linearization circuit, and filtering circuit. The amplification circuit is responsible for amplifying the weak signal output by the bridge to a suitable level for processing, usually using low-noise, low-temperature drift precision operational amplifiers. Due to the thermal resistanceR-TNonlinear characteristics exist (especially in a wide temperature range), and linearization circuits ensure that the output signal is linearly related to temperature through analog compensation or digital algorithms.

Output conversion circuitConverting processed signals into industrial standard signals is commonly done4-20mAThere are also current signals0-10VOr in the form of digital signal output.4-20mAThe current loop has the advantages of strong anti-interference ability and long-distance transmission, and has become the mainstream standard in industrial sites. This part of the circuit usually contains voltage-current(V/I)Converter, output protection circuit, and isolation circuit. Electrical isolation is a key characteristic of transmitters. Through transformer isolation or optocoupler isolation technology, the direct electrical connection between input and output is cut off, effectively preventing ground loop interference and transient voltage damage.

Modern thermistor transmitters typically adopt a compact design that integrates all functions into a sturdy housing, making it easy to install and adaptable to harsh industrial environments. From a system integration perspective, the thermistor temperature transmitter provides standardized signal output and has good compatibility with various control systems. These characteristics make thermistor temperature transmitters particularly suitable for industries with harsh environmental conditions such as power, metallurgy, and chemical engineering.