Contact types (thermocouples, resistance thermometer, etc.) measure the temperature by touching the object. Non-contact types (radiation thermometer) estimate the surface temperature from infrared rays. The type you should use depends on the response speed, ease of installation, and thermal coupling with the object.

Thermocouples detect temperature by electromotive force, while resistance thermometer detect temperature by changes in resistance value. Thermocouples are advantageous for high temperatures and wide ranges, while resistance thermometer are advantageous for accuracy and stability.

This is the time it takes for step temperature change to reach 63% (or 90%). The smaller and thinner the temperature sensor is, and the lower the thermal capacity and thermal resistance, the faster the change will be.

The target temperature is thermally contacted and the influence of the surroundings is reduced by using heat insulating material or thermally conductive grease. For fluids, the temperature is near the center of the flow path, and for solids, it is at a representative point.

Correctly match the sensor type (thermocouple type/ resistance thermometer element/wire type), unit, filter, alarm, and scaling.

shield and twist the cable, keep it away from power lines and inverters, and ground a single-point earth. For long distances, it is effective to use a converter (4–20 mA/IO-Link, etc.).

For thermocouples, balance the material and diameter of the compensating wire, and for resistance thermometer, check the polarity and contact resistance of the connector.

vibration can cause disconnection and poor contact, moisture can reduce insulation, and corrosive gases can cause coating deterioration. Protect with protective tubes, terminal boxes, and the correct IP rating.

Possible causes include insufficient thermal capacity, mismatched response time, improper filter settings, and noise interference. Review the installation and organize the wiring route.

Use freezing point/boiling point, thermostatic chamber, and dry block to compare with a reference sensor. Adjust span/zero if necessary.

Range / Temperature (high temperature is thermocouple), Accuracy and stability (in Japanese history) resistance thermometer (See Section 2.1.2.), response (Micro is thermocouple/thin type) resistance thermometer (See Section 2.1.2.), environment (Compare with (vibration- corrosion resistant). Also take into account the presence of transducers and cable lengths.

When different metals are connected and a temperature difference is applied, a minute voltage (thermoelectromotive force) is generated. The temperature at the temperature measurement point is calculated from this voltage and the temperature of the reference contact (reference thermoelectromotive force table).

K is general-purpose and high temperature, T is low temperature and moisture resistant, J is medium temperature, E is highly sensitive, N is deterioration resistant, and R/S/B are platinum-based and suitable for high temperature furnaces.

I remember that ground types have a fast response but are susceptible to noise, ground types are resistant to noise, and exposed types are the fastest but offer the least protection.

This is a correction that measures the temperature at instrument terminal with a sensor and converts it to a reference temperature of 0°C. This is generally done automatically by the logger or transmitter.

If you connect it backwards, the sign will be reversed. Check the plug/jack symbols and colors (JIS/IEC) before wiring.

Improvements can be made by using a thin sheath, an exposed/ ground type, reducing the heat capacity, and orthogonalizing the flow in the case of a fluid.

Compensating conductors are made of similar materials, and extension conductors are made of the same materials. The golden rule is not to mix types.

Keep away from inverters and high current, ground one side of shield, and use wiring that does not create loops to reduce induction noise.

High temperatures and atmospheric conditions cause metal to deteriorate and characteristic to change. This can be prevented by regular inspection, calibration, and replacement, as well as by selecting the right protective tube.

If heat escapes into the compensating lead wire or protective tube, the reading will be low. This can be improved by shortening the exposed length, insulating, and using thermally conductive grease.

Change from ground to non-ground, review shield ground, and consider the input filter and averaging settings.

Check and calibrate the freezing point, boiling point, and reference temperature source together with display. Also check the soundness of the CJC at the same time.

The combination is based on temperature range, atmosphere (oxidation/reduction/corrosion), response, and durability. terminal box/headless type, diameter, length, and surface condition are also determined.

The electrical resistance of metals changes with temperature. Platinum elements (Pt100/JJPT100/Pt1000) are commonly used and offer excellent repeatability and linearity.

Nominal resistance is 100Ω/1000Ω. For long wiring, Pt1000 is advantageous as it is less affected by lead resistance.

The 2-wire type has the minimum wiring but is greatly affected by lead resistance, the 3-wire type is the standard for industrial use (the same resistance cancels out), and the 4-wire type is ideal for research and calibration purposes.

Reduce errors by keeping the measurement current to the minimum necessary (e.g., 0.1–1 mA), using intermittent excitation rather than continuous energization, and increasing thermal coupling.

time constant is shortened by utilizing a thin film element, a small diameter sheath, spring pressure welding, and thermally conductive grease.

The basic configuration is two wires of the same color and one wire of a different color. Wire according to the A/A'/B markings on terminal to avoid disturbing resistance balance.

Twisted shield, low resistance cable and optionally a transducer (4–20 mA/digital) inside the head will ensure stability.

Deterioration of insulation and leaks can cause errors. Moisture-proof structure, resin sealing, and cable glands prevent intrusion.

The main causes are poor lead resistance compensation, self-heating, and insufficient thermal coupling. Check the 3-wire resistance balance and measurement current.

Enables transmitter sensor break detection and out-of-range alarms, and defines higher limit/lower limit fail limits.

The input linearity of display is confirmed using a reference resistance, and the sensor is checked in a freezing point and constant temperature chamber. Traceable records are kept.

The order high accuracy is AA > A > B. Select based on the required accuracy, temperature range, and cost, and determine based on the uncertainty of the entire system (sensor + input device + installation).

Select based on process conditions and maintainability, such as thin film/winding, sheath diameter, thread/flange/insertion length, and spring-loaded pressure welding.