Coercive Force Meter

Coercivity range: 10~500A / m accuracy:+/-2.5% repeatability: +/-1.0% Sample size: Dia2~30mm, L10~200mm wide application   Use and Features

Relay core, iron yoke, armature and other magnetic materials, such as electric meter compensation films, which are mainly made of pure iron materials, low carbon steel, iron-nickel alloy. Hc value is an important parameter of these materials. Hc value have relation with not only the materials, but also with the machining process by the mechanical stress and heat treatment process. In other words, Hc value of the same magnetic material would be wide different due to many factors in the processing. To the manufacturer of relays, the coercive force is directly related to the quality of the product. Similarly, in the production of mechanical energy meter, the coercive force of the compensation films are also directly related to the adjusting table results of energy meter, and affected production volume and quality accordingly. Therefore, the coercive force meter is the essential measurement instrument of the manufacturers who are producing the relays, energy meters, and other electrical pure iron, low carbon steel measuring the coercive force of open circuit magnetic materials.

1.2 Instrument Use

The meter is mainly used in measuring the coercive force of magnetic components of relays and the mechanical energy meter compensation films, which is the essential instrument of manufacturers who are producing the relays and the energy meters, etc.1.3 Instrument features1.3.1 The instrument used a weak magnetic field gradient coil vibration measurement with the sensors in the condition of zero flux. The sensor has high sensitivity, whose sensitivity is double than the flux magnetometer. 1.3.2 The hardware and software of the measurement do well in the anti-interference ability in the use of the relevant computing, digital filtering, fuzzy algorithms and other advanced technologies.1.3.3 The use of computers in industrial control, with  high reliability.1.3.4 No need of the standard specimen, directly measuring to the product. Various technical indicators have reached the national standard GB3656-83.1.3.5 Measuring not only coercive force but also remanence.1.3.6 Automatically drawing the hysteresis loop in the open-loop state, and automatically recording the data.1.3.7 Different Magnetization time for options to meet the needs of different users.1.3.8 Reality in zero in the measurement of the coercive force.1.3.9 With good reproducibility and high stability.

 Composition and working principle

2.1 Composition

1.   Tested material guide plate

2.   Magnetization magnetic field solenoid

3.   Sensor

4.   Magnetization current wire

5.   Sensor signal line

6.   Wind Pipe

7.   Industrial controlled computer

8. Printer HP1008

 

 

 

                                                                             Figure 1: Diagram Figure of compositions

The main compositions are shown in Figure 1. In addition, as shown in Figure 2 the signal input and output cards inserted in the IPC, as shown in Figure III signal conditioning circuit card and a printer, a dedicated software.

2.2 Working Principle.

The instrument is used in measurement the coercive force of soft magnetic materials under the condition of the open circuit. Its working principle is that in Figure 1, the first by the IPC through the magnetization current line generating the magnetization current, to control of magnetic field, so that the measured sample magnetization to the saturation state of Bs, then demagnetization gradually.

Figure 2. Signal input and output

J1: 220V power connection socket

J2: solenoid magnetization current socket

J3: Power jack of signal conditioning board

J4: switch interface (not used)

J5: switch interface

J6: Analog Interface

J7: Signal Sensor Interface

J8: speaker wire

J9: Speaker Drive Power

R72: speaker AM potentiometer

R61: FM Speaker Potentiometers

Figure III. Signal conditioning circuit card

As the magnetic material has a magnetic effect, when the external magnetic field is zero, but, the magnetic force of magnetic materials is not zero and the existence of residual magnetization Br, at this time the reverse magnetic field is what we measure, i.e. the coercive force Hc, due to some parts of irregular shape, in the measurements can be measured by the forward and reverse magnetization and then take the average as a the final coercive force the materials. Anyway, all measurement would be done automatically by the IPC.

Main technical performance

3.1 The measured parameters: the coercive force, Hc, surface residual magnetization Br 3.2 Coercivity range: 10 ~ 500A / m 3.3 Coercivity Measurement accuracy: ± 2.5% 3.4 Coercivity measurement repeatability: ± 1.0% 3.5 Residual magnetization measuring range: 1 ~ 1000 μT 3.6 With the positive coercivity measurement, the reverse-coercivity measurement and double-way measurements 3.7 Rapid measurement and Accuracy measurement. 3.8 Wide choice for Magnetization time 3.9 Size range of tested parts: Φ: 2 ~ 30mm, L: 10 ~ 200mm 3.10 Working conditions: Power supply: AC 220V+/-10%;Ambient temperature: 5 ~ 28 °C 3.11 Continuous working time: no more than 3 hours