German GENTHERM sensors, GENTHERM models, GENTHERM prices

GENTHERM pressure sensors for level measurement. The static pressure submersible level transmitter (level gauge) is based on the principle that the static pressure of the measured liquid is proportional to its height. It uses advanced imported isolated diffused silicon sensitive elements or ceramic capacitive pressure sensitive sensors to convert static pressure into electrical signals, which are then converted into standard electrical signals (typically 4–20mA/15VDC) after temperature compensation and linear correction.

GENTHERM sensor structure

It consists of two parts: the scale grating and the grating readhead. The figure on the right shows the structure of the grating ruler. The key part of the grating detection device is the grating readhead, which consists of a light source, condensing lens, index grating, photoelectric elements, and adjustment mechanisms. There are many structural forms of grating readheads, classified according to their structural characteristics and application scenarios into direct-receiving readheads (also known as silicon photovoltaic cell readheads), mirror-image readheads, beam-splitter readheads, and metal grating reflective readheads.

GENTHERM sensor principle

The essence of a grating displacement sensor is to measure position using the grating pitch as a standard ruler. High-resolution grating rulers are generally expensive and difficult to manufacture. To improve system resolution, Moiré fringes need to be subdivided; grating ruler sensor systems mostly use electronic subdivision methods. When two gratings overlap with a slight inclination angle, Moiré fringes are generated in a direction roughly perpendicular to the grating lines. As the grating moves, the Moiré fringes move up and down accordingly. This converts the measurement of grating pitch into the measurement of the number of Moiré fringes. Within one Moiré fringe width, placing 4 photoelectric devices at certain intervals enables electronic subdivision and direction determination. For example, for a grating ruler with 50 line pairs/mm, the grating pitch is 0.02mm. With four-fold subdivision, counting pulses with a resolution of 5μm can be obtained, achieving high precision in general industrial measurement and control. Since displacement is a vector, both its magnitude and direction must be detected; therefore, at least two photoelectric signals with different phases are required. To eliminate common-mode interference, DC components, and even harmonics, differential amplifiers composed of low-drift operational amplifiers are typically used. The 4 photoelectric signals obtained from 4 photosensitive devices are sent to the input terminals of 2 differential amplifiers respectively. The two signals output from the differential amplifier have a phase difference of π/2. To obtain direction determination and counting pulses, these two signals need to be shaped, first into square waves with a duty cycle of 1:1. Then, by comparing the phases of the square waves, the movement direction of the grating ruler can be determined. By counting the square wave pulses, the displacement and speed of the grating ruler can be obtained.

GENTHERM sensor usage precautions

Power off before plugging or unplugging the connector between the linear scale sensor and the digital readout. Install an external protective cover whenever possible, and promptly remove chips and oil that splash onto the scale to strictly prevent any foreign matter from entering the linear scale sensor housing. Regularly check whether the mounting and connection screws are loose. To extend the service life of the dust-proof sealing strip, apply a thin, even layer of silicone oil to the sealing strip, taking care not to let it splash onto the glass grating etched surface. To ensure reliable operation of the linear scale sensor, periodically clean and wipe the linear scale surface and the index grating surface with an ethanol mixture (50%) to keep the glass linear scale surface clean. The linear scale sensor must not be subjected to severe vibration or impact, as this may damage the linear scale; if the linear scale breaks, the sensor will fail. Do not disassemble the linear scale sensor yourself, and never arbitrarily change the relative spacing between the main scale and the secondary scale, as this may degrade the sensor's accuracy and cause relative friction between the main and secondary scales, damaging the chrome layer and thus the grating lines, resulting in scrapping of the linear scale. Prevent oil and water from contaminating the linear scale surface to avoid disrupting the grating line pattern and causing measurement errors. Avoid operating the linear scale sensor in environments with severe corrosive effects to prevent corrosion of the chrome layer and the linear scale surface, which would compromise the quality of the linear scale.

Weidou Intelligent Technology specializes in selling German GENTHERM sensors, GENTHERM proximity sensors, GENTHERM distance sensors, GENTHERM vision sensors, GENTHERM displacement sensors, GENTHERM load cells, GENTHERM speed sensors, GENTHERM photoelectric sensors, GENTHERM position sensors, GENTHERM angle sensors, GENTHERM tactile sensors, GENTHERM temperature sensors, GENTHERM pressure sensors, GENTHERM flow sensors, GENTHERM level sensors, GENTHERM motion sensors, and GENTHERM process sensors. Original German imports. Welcome inquiries and orders.