The rotational speed is an important parameter reflecting the operating state of rotating machinery, which is the result of the joint action of rotating machinery power moment, inertia moment, and load moment. Through the measurement of the instantaneous value of the rotational speed, you can quantitatively understand the rotating machinery's internal power generating device's instantaneous working state, understand the load application process, to ensure the normal operation of the equipment, analyze the transient performance of the machinery, mechanical fault diagnosis to provide a basis. There are four main methods for measuring rotational speed, namely, mechanical, electromagnetic, photoelectric, and laser.

1. Mechanical
The mechanical type mainly uses the principle of centrifugal force to drive the free shaft sleeve up and down through a fixed mass weight rotating with the shaft, and obtains the measurement results according to different rotation speeds corresponding to different shaft sleeve positions. The principle is simple and direct. No additional electrical equipment is required, suitable for contact speed measurement occasions with low accuracy requirements.
2. Electromagnetic type
The electromagnetic system consists of an electromagnetic sensor and a tooth disk installed on the shafting. The spindle rotates to drive the teeth to rotate. When the teeth pass through the sensor, the circuit reluctance changes, and a square wave electrical pulse is formed after amplification and shaping. Due to the limitation of the machining precision of the gear disk, the minimum resolution interval of the teeth and the maximum counting frequency of the circuit, the measurement accuracy cannot be guaranteed.
3. Photoelectric type
Due to the flexible photoelectric measurement methods, many parameters can be measured, and under normal circumstances, it has the advantages of non-contact, high precision, high resolution, high reliability and fast response, coupled with the successive emergence and successful application of laser light source, grating, optical code disk, CCD device, optical fiber, photoelectric sensor has been widely used in the field of detection and control.
4. Laser type
Laser velocity sensor is a sensor that can measure the speed of the measured object by laser and convert it into an output signal. With the rise of today's precision manufacturing industry and the need to save costs, non-contact laser speed sensors will slowly replace the current contact speed sensors on the market, laser speed sensors have been widely used. Through the combination of computer technology and measurement technology, the measured object is automated and intelligent measurement control, which is also a development trend of measurement technology.

The most commonly used speed measurement method of the elevator motor is also the proximity sensor. Because the installation is simple and convenient, just install a toothed disk with the number of teeth N0 and N1 respectively at the end of the reel and the spindle, and then install the proximity switch above the toothed disk. When the rotating shaft with the teeth of the gear disc is turned from the end face of the close switch, the close switch will produce a pulse, counting N0 pulses, and the corresponding reel will turn one week, similarly, a pulse represents a spindle turn one week for the gear disc N0=N1 =1, it is the simplest gear disc (no teeth). At this time, just make a hole or install a screw at the end of the shaft, and the corresponding shaft turns around, and a pulse is generated near the switch.

Elevator motor speed measurement applications: IM08B/IM12B/IM18B/IM30B series proximity sensors

1. With good electromagnetic compatibility characteristics
2. It has a certain shielding effect on the side metal
3. Superior anti-frequency converter interference characteristics

I hope the above information can help you choose the right elevator motor speed sensor for you. If you are still not sure which product to choose, you can also contact us via email. G-TEK has the most professional technical service team and sales service team to provide you with the most professional sensor product solutions.