Electromagnetic sensor

Electromagnetic sensors use the principle of electromagnetic induction to achieve the purpose of speed measurement. With a large output signal, good anti-interference performance, no external power supply, can be used in the harsh environment of smoke, oil and gas, water and gas.

When the magnetic gap changes due to rotation of the speed measuring gear, an induced electromotive force is generated in the probe coil. The amplitude is related to the rotational speed. The higher the rotational speed is, the higher the output voltage is, and the output frequency is proportional to the rotational speed. The rotational speed is further increased and the magnetic path loss is increased. The output potential has become saturated. When the speed is too high, the magnetic path loss increases and the potential drops sharply.

1, DC resistance: 150~200Ω(25°C)
2, measured gear form: modulus 2~4 (involute gear)
3, working temperature: -10 ~ +120 °C
4, anti-vibration shock: 20g
5, thread specifications: M16 × 1, M8 × 1 (or customer requirements)

6, shell length: 60 ~ 100mm (user-defined)
7. Measurement range: 10~15000r/min (60 teeth)
8, the output signal amplitude: amplitude> 200mV

Test conditions: The number of transmission gears is 60, the material is electrical steel, the modulus is 2, the rotation speed is 50r/min, and the sensor end face is 0.6mm from the tip of the tooth). The magnitude of the signal amplitude, which is proportional to the speed, is inversely proportional to the size of the end face and tip clearance. The manufacturers of electromagnetic sensors include Zhuzhou Sixth and Eighth Technology Co., Ltd. and the China Aviation Power Machinery Research and Development Center.

9, the output voltage waveform:
Involute gear - Approximate sine wave, if the gear is slightly eccentric, it is amplitude modulated sine wave;
Orifice - approximate square wave

The distance between the end face of the sensor and the top of the tested tooth is 0.25~1.2mm. The best safety distance between the end face of the sensor and the measured gear should be determined according to the actual situation on the site.