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What's kind of sensor we are using for the Automatic Door opener?

January 28, 2021

What's kind of sensor we are using for the Automatic Door opener?


Active Infrared


Functional Principles: An Active Infrared Detector always consists of one transmitter and at least two receiver chips with high-quality optical systems. The scanning range is set by means of a mechanical micro-speed unit by changing the angle between the transmitter and receiver. This optical procedure is called triangulation or optical differential measurement.


Active Infrared Detectors are static—they only detect persons and objects if they break the beam. The detection area consists of spots, and depends to a large extent, on the optical center-to-center distances of the transmitter and receiver lenses. Several beams can be combined in a modular system to form a larger area.


Choose from:


Background suppression presence detectors are used on moving parts like a swing door or revolving door. This system does not require a background like a wall or floor.


Background analysis requires a signal from the background in order to switch the output.


The sensor is installed and requires a background (floor/wall). The output is deactivated.

The desired scanning range is set mechanically within the predefined possible distances.

Each object within the set scanning range is detected statically.

Passive Infrared


Functional Principles: Passive Infrared Sensors function in a similar way to infrared cameras used to detect heat loss from buildings. The infrared-sensitive sensor forms a heat image of the defined area to be monitored. After an initial set-up time of approximately 20 seconds, the measured infrared image is saved. The sensor switches if the heat image changes as a result of movement. Two conditions must be fulfilled here:


1. There must be a temperature difference of +/- 1.8 F between the object to be detected and the background.

2. The object to be detected must move at a rate of at least 4 inches per second.


The system is ideal for detecting people only if— there is always a difference of at least 1.8 F between the surface temperature of a clothed person and the surrounding environment. For reasons of a physical nature, this technology should only be used to detect living beings as it’s not always possible to guarantee that the difference in temperature between items such as shopping carts or vehicles, and that of the surrounding environment will be great enough.


Microwave sensor ( we have 2 models are available to choose, M204 and M204-T)

So, we need to know first what is a Microwave Motion Sensor?

A microwave motion sensor uses electromagnetic radiation. It emits waves that are then reflected back to the receiver. The receiver analyzes the waves that are bounced back. If there is an object moving in the room, these waves are going to be altered. The microwave detector is able to identify changes from moment to moment. 

Ideally, the receiver should be receiving the same waves back again and again.

Because of the way that microwave motion sensors work, they can be either more sensitive or less sensitive. They can identify every minute changes (a totally empty house) or be calibrated to require larger-scale movement (to avoid false positives).

Functional Principles: Microwaves are electromagnetic waves such as those emitted by a radio transmitter but with a much higher frequency (> 1GHz). Thanks to the variable antenna, the microwaves emitted by the transmitter can be directed without any difficulty and are reflected back to the receiver via the floor, walls, and other surfaces.


If there is no movement in the monitored zone, the transmitter and receiver frequency remains the same—the zone is clear. People and objects, however, activate the motion detector as they move through the monitored zone. The emitted and received frequencies are no longer identical. The difference between the frequencies is evaluated and transferred via relay or electronic contacts in the form of a switching pulse. The microwave power used is perfectly safe for humans and animals.


How to Combat Interference, maybe this is one of the questions you want to know...


In addition to known influencing factors such as rain, snow, fluorescent lamps, and fundamental vibrations of door drives, there has also been a steady increase in parasitic interference caused by items such as mobile phones, radio, and X-ray equipment—commonly called electrosmog. Optimized circuits and other suppression components provide extensive protection.


Today, more special features are available. Environmental awareness and energy and cost-savings are not just empty promises anymore. (See application pictures ). Here are some of the features available:


Distinguishing between movement toward and away from the detector. A few known models can even distinguish between cross-traffic and approaching traffic. The separation between people and vehicles, which would allow a door to open differently for a vehicle versus a person.

Setting up a sensor with an easy-to-use remote control is standard today. Two models are known in the market: Unidirectional, where you read the setting by counting blinking LEDs on the sensor; or a bidirectional remote, which allows you to read out the settings and visually show them on the remote.

Different Sensors for Different Applications


The most common doors are sliding, swing, and revolving doors. There are low-cost sensors, which basically can only fulfill one major duty—detection or not. But there are also sophisticated sensors available which not only open a door but can also be used for special applications. For example a hotel entrance door that's activated every time a car pulls up. This action can now be eliminated. Today, there are sensors that will ignore cross-traffic, only activating the doors when a person walks toward it. Many hotel managers will be glad to hear that.


Active infrared sensors are not only being used to activate a door but also to detect presence so a door doesn't close while a person or object is still in the door's path.?


Swing doors are by far the most common automated pedestrian doors in North America. Most swing doors are activated by a sensor and secured by another. We differentiate between a header-mounted sensor and a door-mounted sensor. Header-mounted sensors are often used for activation, but there are also header-mounted sensors available for safety. Door-mounted sensors are basically for presence-detection to assure the door is not closing on a person in the path.


Sliding doors are the second-most used doors in the industry. Generally, the swing door is activated on both sides, and also has some presence features, either by beams in the threshold or a presence sensor. There are also combined sensors available on the market where the activation and presence are included in one unit.


Revolving doors are common, but seldom are they fully automated. A fully automated revolving door requires a set of activation and safety sensors. Activation sensors start the movement of the door; presence sensors assure no one is being hit by a moving door. Often, there is a single beam sensor on the closing edge, a presence detector on the moving leaf, and, in addition, there are mostly electrical sensing edges and safety mats used.

Author: Written by Ms.Anna Zhang from S4A INDUSTRIAL CO.,LIMITED

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  S4A-Security For All.  S4A Industrial Co., Limited, Founded in 2010, We have been dedicating in access control production R&D and sales for 10year till now. With the belief that we do one thing well in a lifetime, our CEO has been in this industry for 15 years. During the past 10 years, our products have been exported to various countries and regions. And 90% of customers come from the recommendations of cooperative customers, and 80% of the turnover comes from cooperative customers in the past 10years.Your business is a plant, we are the gardener, our mission is to water and fertilize the plant, and make it become the towering tree. We attach great importance to the partner's appeal, customer's suggestions, and feedbacks. To strengthen Product quality awareness, client's service awareness. Our clients and S4A are on the same path walking for many years.       S4A's future would be even more brilliant, this is related to all of our staff's working sweat. When you join this team, you will feel an invisible power to drive walk forward. S4A mainly produces a series of security Door Access Control such as:Network Access Controller, Locker board, Electromagnetic lock, Standalone door Controller, Automatic door opener, etcOur team can manufacture products, sell products, and do after-sales.We can create value for you! 1-We put quality and price in top priorityQuality takes great importance for a company's credibility, and buyer's every penny spend must worth it. That is our most basic principle. Our business mainly for wholesale, so we could offer large quantities at competitive prices. During the past 10 years, We work hard to create value for our customers, and with our help, customers have an increasing market share. 99% of the customers who have cooperated with S4A will choose 2nd,3rd, and endless purchasing. because S4A not only controls the product quality very well, but the price is also very reasonable. As you can see, we have hundreds of products, but We do not produce all products. We adopt a portfolio strategy and invest in each factory. Because of the large export volume and the stable cooperation relationship with the factory, we can better control the quality and price of the products. Cooperate with us, you have no worries. In the past 10 years, more than 80% of our customers' sales have increased turnover by 15-20% every year. 2 -We have experienced and professional sales Our sales are not just sold products, we also help you choose products, do market research. Our company's top sales team all have more than 8 years of experience in the access control market, our team loves learning, loves sharing, good at summarizing, and dare to undertake responsibility. Because all of us regard the access control field as a career we love throughout our lives. At S4A, you can get a quick response and flexible support, and you can see our ability to solve problems. get professional guidance and recommendations, you don't have to worry about after-sales at all. Our task is: All emails must be replied within 2 hours at a working time!3-We have experienced and professional engineer S4A is equipped with 6 technical engineers for after-sales. and every year, We take out 20% of the net profit as research and development for new products, We all know Access control system is a kind of product with technical knowledge. When you have headaches such as unable to connect wires, Software compatibility issues or programming device, please remember S4A's after-sales support at any time. Our task is: All technical issues must be solved within 4 hours at a working time!4-Support OEM & ODM  All of our products accept OEM and ODM orders at a reasonable quantity. we help customers to promote their brand. We all know Access control is an increasingly popular industry. Based on past experience, we have found that customers who have just started to become distributors do not have a large number, but want to promote their own brands. For this kind of customer, we will also have a special application to do OEM for him. Because Support is mutual.5. S4A Vision Our Vision is to let all people in the whole world free their hands for keys, whether it is in poor areas or developed cities able to use access control.<
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