According to the user experience summarized using thermocouple frequently asked questions

The precision of all kinds of thermocouple and temperature range is how much?

you can on the thermocouple color code table to find more information about the thermocouple accuracy and temperature range. It's important to remember that precision and range depends on thermocouple alloy, the temperature being measured, the sensor structure, sheath material, the measured medium, medium state ( Liquid, solid) Such as, or gas) And thermocouple line ( If the exposure) Or sheath diameter ( If there is no exposure but sheathed thermocouple wire) The diameter of the.

grounded or not grounded probe should I use?

depending on the instrument. If there is a possible reference to the ground, The controller in the isolated input is common) , you need a probe off ground. If the instrument is portable instrument, it is almost always use grounding detector.

I can use any multimeter measuring temperature thermocouple?

the thermoelectric voltage depends on the size of the specific thermocouple alloy wire closure ( Sensor) As well as the open circuit ( Measurement) End. Using thermocouple temperature sensing instruments to consider the temperature measurement, to determine the temperature on sensor. Most millivoltmeter has no this function, no ability to nonlinear scaling to transform millivolt measurement for temperature. Can use a lookup table to correction and calculate the specific millivolt readings by the temperature of the sensor. But, need to calculate the correction unceasingly, because it doesn't often change over time.

how to choose the thermocouples, resistance temperature detector ( RTD） , thermistor and infrared equipment?

you must consider the characteristics of various sensors and costs and the available equipment. In addition, the thermocouple is usually in a wide temperature range measuring temperature, cheap and very strong, but they are not as accurate as thermal resistance and heat resistance and stability. Thermal resistance is stable, has quite a wide temperature range, but not as strong as thermocouple and cheap. Because they need to use the current is measured, the thermal resistance will be inaccurate by self heating. Thermistor often heat resistance or thermocouple to be more accurate, but their temperature range is more limited. They have also been self heating. Infrared sensor can be used for measuring temperature higher than that of any other equipment, and will not direct contact with the surface to be tested. However, they are usually less accurate and on the surface radiation efficiency ( Or, more accurately, the surface emissivity) Sensitive. Use fiber optic cable, they can measure surface is beyond the scope of direct line of sight.