Temperature sensor products for various industries-From VSEC Elec.
As one of the seven basic dimensions, temperature has more than 400 years of history since the earliest measurement of temperature by humans. Whether in industrial applications or in daily life, accurate temperature measurement is an essential link. With the advancement of technology, temperature sensors have been derived.
1. The difference between temperature sensors
There are many different types of temperature sensors that can be used for temperature measurement. The most common are NTC Thermistor, Thermocouple, Platinum RTD, Digital Temperature Sensor. They have Specific operating parameters make it more suitable for an application. We will use the following table to compare the four common temperature sensors mentioned:
| NTC Thermistor | Platinum RTD | Thermocouple | Semiconductor （digital temperature sensor） | |
| Sensor | Ceramic（metal-oxide spinel） | Platinum wire-wound or metal film | Thermoelectric | Semiconductor junction |
| Temperature Range（typical） | -50 to +300℃ | -200 to +650℃ | -200 to +2800℃ | -70 to +150℃ |
| Accuracy（typical） | 0.05 to 1.5℃ | 0.1 to 0.5℃ | 0.5 to 5.0℃ | 0.5 to 5.0℃ |
| Long-term Stability @100℃ | 0.2℃/year（epoxy） 0.02℃/year（glass） | 0.05℃/year（film） 0.002℃/year（wire） | Variable, some types very prone to aging | ＞1℃/year |
| Output | NTC Resistance | PTC resistance 0.00385W/W/℃ | Thermo-voltage 10mV to 40mV/℃ | Digital,various outputs |
| Linearity | Exponential | Fairly linear | most types non-linear | linear |
| Power Required | Constant voltage or current | Constant voltage or current | Self-powered | 4 to 30 VDC |
| Response Time | Fast 0.12 to 10 seconds | Generally slow 1 to 50 seconds | Fast 0.10 to 10 seconds | Slow 5 to 50 seconds |
| Susceptibility to Electrical Noise | Rarely susceptible High resistance only | Rarely susceptible | susceptible/cold junction compensation | board layout dependent |
| Lead Resistance Effects | Low resistance parts only | Very susceptible. 3 or 4-wire configurations required | None over short runs. TC extension cables required. | N/A |
| Cost | Low to moderate | Wire-wound：High Film：Low | Low | Moderate |
2. Select the required sensor type
When selecting the required temperature sensor, you should first consider the type of temperature sensor. The difference in sensor type directly determines the range that can be measured.
Thermistors are commonly used to measure biological environment temperature (-10 ～ 100 ℃), such as body temperature, water temperature, refrigerator, stove, etc. The small volume and fast response speed make it widely used in daily life.
Thermocouples are frequently used in the industrial field because of their wide temperature range (-200-2800 ℃) and no external power supply is needed. Common types of thermocouples include J, K, T, E, R, S, B, N, each The types of thermocouples have corresponding advantages. The most common types are J, K, and T thermocouples.
Platinum resistors are often used in laboratory environments and medical applications because of their excellent stability and accuracy (0.1-0.5 ° C), but they are the most expensive of all sensors.
The digital temperature sensor is a digital model for transmission, which is easy to collect, transmit, and analyze, and the range temperature (-70 ~ 150 ℃) is suitable for the biological environment and is widely used in the wireless transmission field.
3. Select the required installation environment
Due to the different test environment and safety factors, temperature sensors are often processed into temperature sensor probes. The sensor is packaged with different materials to ensure the stability and service life of the sensor. VSEC Elec. Will provide the most comprehensive sensor sealling solutions and products (The official website www.vsec.top for details).