Thermal resistance temperature transmitter

1 main technical parameters

Input signal: thermal resistance Pt100, Cu50, Cu100, measuring spacing 10 ° C, any temperature range above

Basic error: ±0.5%

Temperature drift: ±0.1%/10°C

Transmission method: two-wire transmission

Power supply: 24V DC ± 2V (or power distribution, safety barrier power supply)

2 main features

Analog features

● High precision

● Range, zero externally continuously adjustable

● Good stability

● Up to 500% positive migration and 600% negative migration

●Two-wire system

● Damping adjustable, overpressure resistant

● Solid sensor design

● No mechanical moving parts, less maintenance

● Light weight (2.4kg)

● Full range of unified structure and strong interchangeability

● Miniaturization (166mm total height)

● Optional diaphragm material for contact with media

● Single side anti-overpressure

● Low pressure cast aluminum alloy shell

Intelligent features:

●Super measurement performance for pressure, differential pressure, liquid level, flow measurement

●Digital accuracy: +(-)0.05%

● Simulation accuracy: +(-)0.75%+(-)0.1%FS

● Full performance: +(-)0.25FS

● Stability: 0.25% 60 months

● Range ratio: 100:1

● Measurement rate: 0.2S

● Miniaturized (2.4kg) all stainless steel flange for easy installation

● Process connection is compatible with other products for optimal measurement

●The world's only sensor with a H alloy sheath (patented technology), achieving excellent cold and thermal stability

●Intelligent transmitter with 16-bit computer

● Standard 4-20mA with digital signal based on HART protocol, remote control

● Support for upgrades to fieldbus and field control based technologies.

3 instrument selection

Selection table: No S code measurement range ABGAP-2400 0-6～40kPa ABGAP-2500 0-40～250kPa ABGAP-2600 0-0.16～1kPa ABGAP-2700 0-0.4~2.50KPa ABGAP-2800 0-1.6～10Mpa Code structure material flange joint exhaust / drain valve isolation diaphragm filling liquid F22 316 stainless steel 316 stainless steel 316 stainless steel silicone oil F23 316 stainless steel 316 stainless steel Hastelloy C F24 316 stainless steel 316 stainless steel Monel F25 316 stainless steel 316 stainless steel 钽 F33 Ha Alloy C Hastelloy C Hastelloy C F35 Hastelloy C Hastelloy C 钽F44 Monel Monel Monel Code Option M1 O～1 00% Linear Indicator M2 Digital Display Head M3 LCD Head B1 pipe bending bracket B2 plate bending bracket B3 pipe fitting flat bracket D1 flange side exhaust / drain valve in the upper D2 flange side exhaust / drain valve in the lower E1 ordinary cable connector E2 explosion-proof cable connector G1 waist Flange G2 welded pipe joint d flameproof i intrinsically safe

4 system components

The structure of the thermal resistance temperature transmitter can be roughly divided into three parts: input bridge, amplification circuit and feedback circuit. Its input bridge is essentially an unbalanced bridge. The thermal resistance is connected to one of the bridge arms. When the resistance of the thermoelectric resistance changes due to the temperature change, the bridge outputs an unbalanced voltage signal. The voltage signal is passed through the amplifying circuit and the feedback circuit to obtain an input signal. The output current I is a linear function.

5 thermal resistance

(1) Thermistor temperature measuring system generally consists of a thermal resistor, a connecting wire and a display instrument. The following two points must be noted:

1The thermal resistance and the index number of the display instrument must be the same

2 In order to eliminate the influence of the change in the resistance of the connecting wire, a three-wire connection method must be used. See Chapter 3 of this chapter for details.

(2) The outer diameter of the armored thermal resistance armored thermal resistance is generally φ1~φ8mm, and the minimum is φmm. Compared with ordinary type thermal resistance, it has the following advantages:

1 small volume, no air gap inside, thermal inertia, small measurement lag;

2 good mechanical properties, vibration resistance, impact resistance;

3 can be bent for easy installation

4 long service life.

(3) End face thermal resistance end face thermal resistance The temperature sensing element is wound by a specially treated resistance wire and is closely attached to the end face of the thermometer. Compared with the general axial thermal resistance, it can reflect the actual temperature of the tested end face more correctly and quickly, and is suitable for measuring the end face temperature of the bearing bush and other parts.

(4) Explosion-proof type thermal resistance flameproof type thermal resistance through the special structure of the junction box, the explosive mixture inside the casing is damaged by the spark or arc and other shadow resistors must change the length of the resistance wire and affect the resistance value. It is better to replace the new resistor body for this purpose. If welding repair is used, it must be verified after welding to be used.

6 structural features

(1) Mastery type thermal resistance : The structure and characteristics of the common thermal resistance temperature sensing element (resistor) in the industry. From the temperature measurement principle of the thermal resistance, it is known that the change in the measured temperature is directly measured by the change in the resistance of the thermal resistance. Therefore, changes in the resistance of various wires such as the lead wires of the thermal resistor body may affect the temperature measurement. To eliminate the influence of lead resistance, a three-wire or four-wire system is used.

(2) Armored thermal resistance: The outer diameter of the armored thermal resistor is generally φ2~φ8mm, and the minimum is φmm. Compared with ordinary type thermal resistance, it has the following advantages:

1 small volume, no air gap inside, thermal inertia, small measurement lag;

2 good mechanical properties, vibration resistance, impact resistance;

3 can be bent for easy installation

4 long service life.

(3) End face thermal resistance : The end face thermal resistance temperature sensing element is wound by a specially processed resistance wire and is closely attached to the end face of the thermometer. Compared with the general axial thermal resistance, it can reflect the actual temperature of the tested end face more correctly and quickly, and is suitable for measuring the end face temperature of the bearing bush and other parts.

(4) Explosion-proof type thermal resistance : Explosion-proof type thermal resistance is limited to the explosion caused by spark or arc in the explosion-mixing gas inside the casing through a special structure junction box, and the production site will not be cited. Super explosion. Explosion-proof thermal resistance can be used for temperature measurement in explosion-prone areas in the Bla~B3c class.

7 verification method

1. Equipment requirements: one calibrator; [1]

2, according to the system connection method wiring;

3. According to the sensor and range indicated on the transmitter nameplate, input the corresponding resistance value so that the output is 1V and 5V (the zero potentiometer and the full potentiometer can be adjusted separately);

4. Input the resistance values ​​according to the range of ten equal points, and check whether the temperature output meets the accuracy range;

5, according to the technical indicators of the specification for testing, should meet the technical requirements.