Temperature Sensor Simulator – RTD, Thermocouple & More

October 26, 2026 4instrumentation20

How Temperature Sensors Measure Temperature

All temperature instruments turn a physical effect of heat into something we can read: a longer column, a bent strip, a voltage, a resistance, light. Pick a sensor (14 types: dial gauge, thermocouple, RTD, handheld IR gun, thermal camera, two-colour pyrometer and more), heat or cool the process, and watch what happens inside the sensor, how the signal travels to the 4 to 20 mA output, and what can go wrong.

From temperature to 4-20 mA (signal chain)

Sensor signal, conditioning electronics, ADC (analog to digital converter), microprocessor (linearises, compensates and scales to a temperature), then the 4-20 mA output. Mechanical types and handheld instruments are normally local indicators; here they are shown as if fitted with an electrical pickoff.

How it works

About this sensor type

What changes with temperature
Typical measuring range
Typical accuracy
Best for
Weak point
Response time constant (bare)

1Choose a sensor type

2Change the process temperature

Transmitter range

Process temperatureC

3Installation and environment

Ambient temperature

Install in a thermowell (protection)

Compensation ON (cold junction / capillary)

Thermocouple type

RTD wiring

Cable resistance per wire

Real surface emissivity

Emissivity set in instrument

Dust / steam in the path

Gun distance to target

Contact sensors need time to heat up (thermal time constant), and a thermowell protects the sensor but slows it down. Infrared instruments read from a distance with no contact.

Transmitter readings

Process temperature
Sensor temperature (after heating up)
Sensor raw signal
Digital value (16-bit)
Temperature read by transmitter
Output (% of span) and current
Measurement error

Response to a temperature change

grey dashed = real process temperature, blue = what the transmitter reads. Last 60 s. The gap is the lag of the sensor.

Sensor signal vs temperature

x: temperature across the transmitter range, y: raw sensor signal (% of its change over the range). Orange dashed = a perfect straight line. A curved line means the microprocessor must linearise the signal.

Compare all sensor types

Temperature Sensor Simulator

The Temperature Sensor Simulator is an interactive learning tool designed to explain how different temperature sensors work in industrial applications. Explore RTD Pt100, thermocouples, thermistors, bimetallic sensors, infrared pyrometers, and other temperature measurement technologies.

Change the process temperature and observe how different sensors respond. Understand their working principles, response time, and output characteristics through simple visual simulations.

This simulator is useful for instrumentation engineers, technicians, and students learning industrial temperature measurement, process control, and temperature transmitter fundamentals.

Explore the simulator below to improve your understanding of temperature sensors used in power plants, refineries, and process industries.