The access controller is the core data processing and storage part of the access control system, and it is the soul of the access control system.

The usual classification of access controllers.

1. According to the communication mode of the controller and the management computer, it is divided into: RS485 networked access controller TCP/IP networked access controller.

The RS485 networked access controller usually also has the RS232 serial port communication mode, through the RS232 serial port and the computer for stand-alone communication.

2. According to the number of doors controlled by each controller, it can be divided into: single-door controller/double-door controller/four-door controller;

There are also 8-door, 16-door, and 32-door controllers on the market, which are very inconvenient in terms of aesthetics in construction and wiring, and because there are too many lines entering the mainframe chassis, it is easy to cause interference and instability. The number of doors controlled by the controller does not reflect the advanced design of the product, but it brings about a negative stability impact, and the inconvenience of construction has a greater impact.

3. According to the number of card readers that can be connected to each door, the controller is divided into: one-way controller, two-way controller

If you enter a door, swipe your card, and press the button when you go out, the controller can only connect to one card reader for each door. We call it a one-way controller.

If there is a door, swipe the card when entering the door, and swiping the card when going out (you can also connect the door exit button), each controller can be connected to two card readers for each door, one is the door reader and the other is the exit card reader, we call it Two-way controller.

Remarks: If the two-way controller is connected to the door card reader only, the door reader is not connected to the door (the port is idle), and the door is opened by the door button when you go out. The function equivalent to a one-way controller is also possible.

Here we need to distinguish the concept of "double-opening door". Some doors can be opened and opened, and can be opened inward or outward when called. This has nothing to do with the classification of the access controller. There is also the concept of "double-leaf doors". Some doors, such as the glass door of the company gate, consist of two left and right doors, but each door is equipped with an electric lock, and the two locks are connected in parallel to one of the controllers. Just click on the relay of the door. There is no need to use a double door controller, only a single door controller can control the double door.

How does the access control system realize the linkage with the fire protection system.

The fire-fighting linkage alarm expansion board of the controller of the access control system has a dedicated interface for connecting and receiving fire-fighting signals. Once received from the fire alarm and broken glass switch and other fire equipment issued by the closed fire signal. All the doors of the controller where the expansion board is located will automatically open to facilitate quick escape of personnel, and the related siren will be driven by the relay on the expansion board to remind personnel to escape. After the fire signal is released, the door automatically resets and the alarm is automatically released.

What is interlocking? How to realize AB door interlock or multi-door interlock function

The so-called "interlock" is two doors, one of which must be closed before the other can be opened by swiping a card or pressing a button. It is a kind of anti-tailing function, which is mainly used in strict occasions such as bank savings bank vaults.

Interlock is also called "AB door interlock", "two door interlock" and "two door".

Feature: Both doors are closed, and you want to open both doors by swiping the card at the same time, the system only allows one door to be opened. Before one door is closed, the other door cannot be opened by swiping the card.

Remarks: To realize the interlock function, the door corresponding to the access controller must be equipped with a door sensor (or use an electric lock with a door sensor), and the signal must be connected to the controller.

What is anti-passback (anti-tailing)? How to realize anti-passback?

Anti-passback is an anti-tailing function of the access control system. In some special access control occasions, the card holder must swipe the card to enter from a certain door and then must swipe the card to exit from a certain door. The credit card record must correspond strictly to one entry and one exit.

This function has the following characteristics:

If someone enters this door with someone else, he does not swipe his card. Next time, he will not be able to swipe his card out, even if his card is valid. Similarly, if you follow others out without swiping your card, you won’t be able to get in next time.

If a person swipes a card to enter the door, and passes the card through the window to the person outside, the person outside cannot enter the door by swiping the card.

If a person does not enter the door after swiping his card, he will not be allowed in next time.

This function is generally used in military, national defense scientific research and other strict management occasions.

The above is the most common anti-pass back inside and outside the door. Two-door and four-door controllers can also realize that the two doors of the same controller can be anti-passback to each other. That is: the card holder enters from door A and must exit from door B. This function is mainly used for channel management and ticket management.

What is the first card to open the door? How to open the door with the first card?

The so-called "first card to open the door" means that after a certain door requires any one of certain people to swipe the card, other people can swipe the card normally.

Case 1: The company's door-opening plan: A company has 5 managers and 30 employees. It is required that after any one of the management staff arrives to swipe the card in the morning, the employees can swipe the card to enter normally. If none of the five administrators has come to swipe the card, other employees can't enter by swiping the card. You must wait for one of the five administrators to come and swipe your card. After get off work, the system automatically switches to only the administrator can enter by swiping the card, and other employees are not allowed to enter.

Case 2: The plan of the embassy and other external office units: the embassy requires the embassy management staff to swipe the card in the morning, the door automatically keeps open. It is convenient for outsiders to come and go freely. After get off work in the afternoon, it will automatically switch to the state of swiping card. Internal personnel need to swipe the card to pass, and external personnel cannot enter.

What is multi-card authentication? How to realize the more demanding multi-card opening function?

The so-called multi-card opening refers to certain specific access control

The occasion needs to enable this function: that is, several people are required to be present at the same time, and the door will be opened by swiping cards one by one. Someone arrives alone and the door cannot be opened by swiping the card.

This function is generally used in bank vaults, antique collection places, museums, troops, and firearms warehouses. The system can be set to multi-card entry and single-card exit to open the door, or it can be set to multi-card entry and multi-card exit is required.

For example: you can set the door to open as many people as they come, or you can open the door with multiple groups and cards, up to 8 groups.

Case 1: Simple multi-card opening: A company has the right to enter and exit the financial room, including general manager, deputy general manager, financial cashier and many others. The company stipulates that two people must come to open the door at the same time before the door is opened to ensure the safety of the financial room.

Case 2: Multiple groups cooperate to open the door. (Maximum 8 groups, such as bank leader group security group, etc.) For example, in the bank vault application, when opening the vault door, 3 bank leaders must come to 1 person, 8 security guards must come to 2 people, and 5 mortgagers must come There are 3 people, all of whom are there as required, and the door will be opened legally after swiping the card in turn.

Case 3: The door is opened by multiple cards in a group. (Maximum 8 teams) For example, a bank treasury manager has three teams, morning shift, middle shift and evening shift. The bank requires at least 3 people in each team to be present at the same time.

Case 4: A privileged person opens the door. And the general system requires multiple cards to open the door, but people in the privileged group, such as the company leader, can open the door by one person.

How to connect the remote control to the access control system

In some occasions, the external remote control of the access control system is usually required: you do not need to get up and press the door button beside the door to open the door for the visitor, carry the remote control with you, press the remote control, the door opens, and the visitor is released.

Precautions for purchasing the remote control:

The remote control has two states: State 1: Press the remote control button, the relay will act, let go, and reset. State 2: Press the ON button to activate the relay, and press the OFF button to reset the relay. Most remotes have these two state options, according to the remote control manual jumper settings

Enter state one, or buy a remote control with state one directly.

How does the access control system control the automatic door.

What is an automatic door? Automatic doors are generally used in some occasions that require frequent entry and exit of people (banks, government offices, shopping malls, companies, etc.). The infrared or microwave sensor (probe) on the top of the door senses that someone needs to enter or leave, drive the motor, and automatically pan open. The glass door closes automatically after personnel leave.

Now many customers want to install an access control system on the automatic door, so that the automatic door opens after the legal person swipes the card. When they come out, they can choose to open the door after the card is confirmed, or the person can open the door directly. Safety elements are incorporated into the convenience and luxury of automatic doors.

Implementation method: single-door two-way access control controller as an example

The infrared probe of the automatic door generally has 4 wires to connect to the terminal of the automatic door control board, two of which are power wires, so don't care. The other two are control wires, which are disconnected at the wiring point of the automatic door control panel. The original terminals connected to these two wires are respectively connected to the COM and NO of the relay output of the access controller. If there is a power supply connected to the COM, please remove it. Because the automatic door needs a switch signal, not an electrical signal.

After wiring, set the authorization card authority and door opening delay time. In this way, a good automatic door access control management can be realized. If you have to swipe your card when you come out, the method is the same.

How to use the access controller to control the electric door and realize the function of swiping the card to open the electric door? What precautions?

Electric doors are management equipment that controls the entry and exit of personnel or vehicles. They are generally installed at the gates of factories, communities, or hotels.

Generally, the electric door has three function buttons, namely, open, pause, and close. What the access control system can achieve is the control of the door opening function, and the suspension and closing functions of the electric door are controlled by the electric door. Most of the old models of electric doors are controlled by manual buttons. Some doors are reserved for automatic closing and automatic anti-pinching design. After the door is opened in place, it can automatically close when there is no obstacle. This function belongs to the function of automatic door, and the access controller is temporarily unable to control it.

Wiring principle and precautions

The principle is that there are three buttons on the operation end of the electric door, by a wire, and a common wire. Connect this wire and the common wire of the door open button to the NO and COM of the relay control end of the access controller. In this way, the automatic door can be opened by swiping the card.

The frequent on and off current and voltage of the electric door button will cause greater interference, and even may cause a crash or restart, you can install an intermediate relay or other isolation control circuit, so that the product can run stably for a long time.

How to use the access controller to connect with three roller gates, barrier gates and other equipment? What precautions?

"Three roller gates": It is a strict management tool for pedestrian passages, such as: subway entrances and exits, parks and attractions entrances and exits.

Principle connection method: Connect the COM and NO output from the relay of the access control controller to the corresponding three turnstile and barrier enabling control points. Three turnstiles have one-way and two-way, two-way (forward and reverse), need two card readers and a two-door controller to control. If there is strong interference, which causes the controller to restart and crash, consider using the access controller relay to control an external large relay and then control the three turns to reduce the interference.

The inrush current and other disturbances generated by the three turnstile itself are relatively large, which will have a certain impact on the stability of the controller, and severely will cause the controller to restart and crash. Therefore, when connecting three turnstiles or barriers, it is best to perform wiring and operation under the guidance of the manufacturer's technicians to ensure the stability of the system. For example: In fact, there are many models of three turnstiles that have photoelectric isolation anti-interference measures, but many engineering companies will not use them.

How to use the fingerprint reader with the access control system? How can other biometrics (iris, palm shaper, etc.) be used in conjunction with the access control system?

Fingerprint equipment manufacturers generally also produce fingerprint access control machines, which integrate fingerprints and access control functions into one machine. This type of access control machine has relatively simple functions and can only be used in occasions with general functional requirements and low security requirements. "Fingerprint + Access Controller" can be used in occasions and fields that require more professional functions and higher security requirements.

What kind of equipment can be connected to the access controller? As long as the fingerprint device (fingerprint reader, fingerprint attendance machine, fingerprint access control machine, etc.) with Wiegand26 output format (the fingerprint number or card number is output in this format after the authentication fingerprint is legal) can be connected to the access control controller, more than 80% on the market All fingerprint devices have wiegand26 output.

For example, iris, palm-shaped device, face recognition, etc., when combined with the access control system, the principle is the same as the fingerprint head combined with the access control system. As long as the device with wiegand26 output can be connected to the access controller.

How to use the battery so that the access control can continue to be used normally after a power failure? What precautions? How to choose batteries and calculate battery life?

Generally, the electric locks that are forbidden on doors are all electric locks that can be opened after a power outage, because this kind of electric lock meets the fire protection requirements. If you want the access control system to work normally after a power failure, there are two ways:

Self-contained battery charging scheme: use the original battery charging and discharging function of the access controller.

The power supply comes with a standard battery, which can supply an electric mortise lock (the access control system mainly consumes electric locks, so the power consumption is calculated by the number of locks.) 4-8 hours, if the time is not enough, it can be connected in parallel, and the parallel connection is not too large. As a side effect, the battery life can be extended by as many times as the battery is connected in parallel, but the charging time will also be doubled. The storage battery has a service life. It is recommended to replace the battery every 1-2 years. The battery life of the expired battery is obviously weakened, or even cannot be charged at all.

External UPS solution: Use UPS uninterruptible power supply to supply power to the controller. Professional UPS has fast charge and overcharge protection, and the cost is relatively high. The cheapest UPS with a 7Ah battery is more than 200. The power is doubled, but the price is several times more expensive. Because the circuit is more sophisticated, it consumes more power. A UPS with a standard battery can only supply an electric mortise lock for access control equipment for 2-4 hours.

Factors affecting the quality and safety of access control controllers:

1. Controller distribution: The controller must be placed in a special weak current room or equipment room for centralized management. The controller and the card reader have the ability to transmit signals over a long distance. Try not to use the general Wiegand protocol, because the Wiegand protocol only It can transmit a distance of tens of meters, so the access controller must be placed close to the card reader, which is not conducive to the management and security of the controller. The distance between a well-designed controller and the card reader should not be less than 1200 meters, and the distance between the controller and the controller should not be less than 1200 meters.

2. The anti-damage measures of the controller: the controller chassis must have a certain degree of anti-smashing, anti-prying, explosion-proof, fire-proof, and anti-corrosion capabilities to prevent various illegal damage events from happening as much as possible;

3. The power supply of the controller: The controller must have a UPS system inside. When the external power supply is not available, the access controller can at least continue to work for a few hours to prevent someone from cutting off the power and causing the access control to be paralyzed;

4. The alarm capability of the controller: The controller must have various instant alarm capabilities, such as failure prompts of various equipment such as power supply and UPS, warning messages of opened chassis, and communication or line failures, etc.;

5. Processing of switch signal: It is better not to use switch signal in the access control controller. Many signals in the access control system will be output in the form of switch, such as door sensor signal and exit button signal. Because the switch signal only has short circuit and There are two states of open circuit, so it is easy to be used and destroyed, which will greatly reduce the overall security of the access control system. The switch signal can be converted and transmitted to improve safety, such as converting it into a TTL level signal or a digital signal, and so on.

Factors affecting the stability and reliability of the access controller:

1. Design structure: The overall structural design of the access control controller is very important. A well-designed access control system will try to avoid the use of slot-type expansion boards to prevent poor contact caused by oxidation due to long-term use; use reliable connectors , Convenient wiring and firm and reliable; the distribution of components and line direction is reasonable, reducing interference, and at the same time enhancing anti-interference ability; the chassis layout is reasonable, and the overall heat dissipation effect is enhanced. The access controller is a special control device and should not blindly pursue the use of the latest technology and components. The processing speed of the controller is not that the faster the better, nor the more concentrated the number of doors, the better, but the stability and reliability must be emphasized. A sufficient and stable access controller is a good controller;

2. Power supply part: The power supply is a very important part of the access control controller. The stable and clean working voltage provided to the components is a necessary prerequisite for stability. However, the 220-volt mains is often unstable, and the voltage may be too low or too high. High, fluctuation, surge, etc., which require the power supply to have good filtering and voltage stabilization capabilities. In addition, the power supply also needs to have a strong anti-interference ability. The so-called interference includes high-frequency induction signals, lightning strikes, and so on.

The uninterruptible power supply inside the controller is also necessary, and the uninterruptible power supply must be placed inside the controller chassis to ensure that it cannot be easily cut off or damaged;

3. Controller programming: Quite a lot of access controllers completely rely on computers and software when they perform some advanced functions or realize linkage with other weak electronic systems. Because computers are very unstable, this may mean Once the computer fails, it will cause the entire system to malfunction or paralyze. Therefore, all the logic judgments and the application of various advanced functions in a well-designed access control system must be completed by the hardware system of the access control controller, that is to say, it must be realized by the program of the controller. Only in this way, the access control system is the best Reliable, and also has the fastest system response speed, and will not reduce the response speed and performance of the entire access control system with the continuous expansion of the system;

4. The capacity of the relay: the output of the access controller is controlled by the relay. When the controller is working, the relay must be opened and closed frequently, and an instantaneous current flows through each time it is opened and closed. If the capacity of the relay is too small, the instantaneous current may exceed the capacity of the relay, which will soon damage the relay. In general, the capacity of the relay should be more than 3 times greater than the peak current of the electric lock. In addition, the output terminal of the relay is usually connected to a large current inductive device such as an electric lock, and the instantaneous on and off will produce the impact of the feedback current, so the output terminal should be protected by components such as a varistor or a reverse diode;

5. Controller protection: The working voltage of the components of the access control controller is generally 5 volts. If the voltage exceeds 5 volts, the components will be damaged and the controller will not work. This requires that all input and output ports of the controller have dynamic voltage protection, so as to prevent possible large external voltage from being loaded on the controller and damage the components. In addition, the controller also needs to have anti-misconnection and anti-surge protection measures in the card reader input circuit. Good protection can make the circuit not burnt even if the power supply is connected to the card reader data terminal. It can be protected by anti-surge dynamic voltage protection. Avoid affecting the normal operation of the controller due to the quality of the card reader.

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