The influence of ambient temperature on platinum resistance, the factors that affect the resistance

The resistance increases regularly with the uniform velocity of the temperature!

Platinum resistance pt100 indexing table.

50 degrees ohms.

40 degrees ohms.

30 degrees ohms.

20 degrees ohms.

10 degrees ohms.

0 degrees ohms.

10 degrees ohms.

20 degrees ohms.

30 degrees ohms.

40 degrees ohms.

50 degrees ohms.

60 degrees ohms.

70 degrees ohms.

80 degrees ohms.

90 degrees ohms.

100 degrees ohms.

110 degrees ohms.

120 degrees ohms.

130 degrees ohms.

140 degrees ohms.

150 degrees ohms.

160 degrees ohms.

170 degrees ohms.

180 degrees ohms.

190 degrees ohms.

200 degrees ohms.

This is the nature of the metal, and the temperature height resistance becomes larger.

Summary. Glad for your question. Yes.

When using, the temperature is determined according to the resistance value lookup table, and the change rate per Celsius ohm is the standard platinum resistance used in the market, which is also linear within the specified range, and the platinum resistance is linear with temperature.

Glad for your question. Yes. When using hail letter according to the resistance value lookup table to determine the temperature, the rate of change source slag wheel for each degree Celsius change beam ohm is the standard platinum resistance used in the market, but also within the specified range of linear, when the measurement is less than the resolution, the sensor must not react.

Right. Yes.

The internal structure of the platinum resistance is that the platinum wire is wound around a bracket made of mica sheets, and the end of the platinum wire is connected to the silver electrode.

Right. The mica platinum resistive element is tied to the sheet bracket formed by the mica sheet with Chunxian pure platinum wire, and the two sides of the winding resistance are insulated with mica sheets, and then the petal-form clamping parts made of metal sheets are riveted together with them on both sides. The outlet end of the platinum wire winding is welded with the lead wire made of silver hunger wire, and is protected and insulated by a porcelain sleeve.

That's right. Yes.

There are two types of sensors, depending on the nature of the output.

There is no such classification.

At present, there is no unified Zhengling classification method for sensors, but there are three more commonly used ones: 1. According to the physical quantity classification of the sensor, it can be divided into displacement, force, speed, temperature, flow, gas composition and other sensors 2. According to the working principle of the sensor, it can be divided into resistance, capacitance, inductance, voltage, Hall, photoelectric, grating, thermocouple and other sensors. 3. According to the nature of the output signal of the sensor, it can be divided into:

The output is a switching quantity ("1" and"0" or "on" and "off"); The output is an analog sensor; The output is a digital sensor with pulse or **. About the classification of sensors:1

According to the measured physical quantity: such as: force, pressure, displacement, temperature, angle sensor, etc.; 2.

According to the working principle of the sensor, it is divided into: strain sensor, piezoelectric sensor, piezoresistive sensor, inductive sensor, capacitive sensor, photoelectric sensor, etc.; 3.

According to the way the sensor converts energy, it is divided into: (1) energy conversion type: such as:

piezoelectric, thermocouple, photoelectric sensors, etc.; (2) Energy control type: such as: resistive, inductive, Hall and other sensors, thermistors, photoresistors, moisture resistors, etc.; 4.

According to the working mechanism of the sensor: (1) Structural type: such as:

inductive, capacitive sensors, etc.; (2) Physical type: such as: piezoelectric, photoelectric, various semiconductor sensors, etc.; 5.

According to the form of the sensor output signal: (1) analog: the sensor output is an analog voltage; (2) Digital:

The output of the sensor is digital, e.g. encoder sensor.

The design, manufacture, and installation specifications of platinum RTDs revolve around a central requirement that the resistance value is only temperature-dependent.

The factors that affect the measurement in actual use are:

Measurement hysteresis caused by thermal inertia of the protective tube;

Changes in the physical and chemical properties of platinum thermal materials caused by corrosion and oxidation;

Faults caused by the quality of assembly materials, such as platinum thermal resistance, the upper limit of theoretical measurement is 650, but many products have problems after 400 days of continuous operation.

Caused by non-standard installation, such as wire resistance, water ingress ......

The main thing is the temperature.

Platinum resistance is a linear proportional relationship between the resistance value and the temperature within a certain range.

Therefore, platinum resistance is used as a thermometer in engineering to measure the non-electric analog value of temperature, and the non-electric power is converted into electric power for measurement.

The thermal resistance is designed and made by using the basic principle that the resistance value of the platinum wire changes with the change of temperature, and is divided into 10 ohms (the index number is pt10) and 100 ohms (the index number is pt100) according to the size of the resistance value r ( ) at 0, and the temperature measurement range is larger, suitable for -200 850The temperature sensing element of 10 ohm platinum thermal resistance is wound with thicker platinum wire, and the temperature resistance is significantly better than that of 100 ohm platinum thermal resistance, which is mainly used in the temperature zone above 650: 100 ohm platinum thermal resistance is mainly used in the temperature zone below 650, although it can also be used in the temperature zone above 650, but no grade A error is allowed in the temperature zone above 650.

Platinum resistance temperature sensors are temperature sensors used to measure air, soil, and water. The sensor consists of a precision platinum RTD element and a specially treated protective sleeve, and is led out of the sensitive element with a four-core shielded signal cable for measurement, which can usually be measured using the four-wire measurement method to reduce the measurement error caused by the resistance of the wire. Platinum resistance temperature sensors have excellent interchangeability and long-term stability, and are widely used in meteorological and environmental protection departments.

According to the definition of resistance, r=u

i can be seen that the slope of the line connecting the point and the coordinate origin on the u-i graph line is equal to the resistance, and the resistance of the metal platinum increases with the increase of temperature, then the slope of the connection between the point on the graph line and the coordinate origin gradually increases, the graph line is a curve, according to the mathematical knowledge, b is correct, so b is selected

The resolution of 100 ohm platinum RTD is 10 times larger than that of 10 ohm platinum RTD, and the requirements for secondary instruments are correspondingly an order of magnitude more, so 100 ohm platinum RTD should be used as much as possible for temperature measurement in the temperature area below 650.

The material of the temperature sensing element skeleton is also the main factor that determines the temperature zone of platinum thermal resistance, and the common temperature sensing elements are ceramic elements, glass elements, and mica elements, which are made of platinum wires wound on the ceramic skeleton, glass skeleton, and mica skeleton and then processed by complex processes. Due to the different properties of the skeleton material itself, ceramic elements are suitable for temperature zones below 850, and glass elements are suitable for temperature zones below 550. There are a large number of thick film and thin film platinum thermal resistance temperature sensing elements on the market, thick film platinum thermal resistance elements are printed on the glass or ceramic base plate with platinum paste, thin film platinum thermal resistance elements are sputtered on the glass or ceramic bottom plate with platinum slurry, and then processed by photolithography, this temperature sensing element is only suitable for -70 500 temperature zone, but this temperature sensing element is material-saving, can be mechanized mass production, high efficiency, and cheap Zhixin.

In terms of structure, platinum thermal resistance can also be divided into industrial platinum thermal resistance and armored platinum thermal resistance. Industrial platinum thermal resistance is also called assembling platinum thermal resistance, that is, the platinum thermal resistance temperature sensing element is welded with a lead and assembled in a metal tube or ceramic tube closed at the end of the slippery partner, and then installed on the junction box; Armored platinum thermal resistance is the platinum thermal resistance element, transition lead, insulating powder assembled in the stainless steel pipe and then compacted by the mold as a whole, with the advantages of solid, shock-resistant, windable, small wire diameter, easy to use and install.