In a modern community, smart access control is definitely indispensable, because the emergence of access control effectively solves the problem of unnecessary security problems for the community, such as sending small advertisements, promoting products, and other bad behaviors that are unfavorable to property management. Greatly improve the safety of the community.

The access control system refers to the prohibition authority of the "door", which is the guard against the "door". It usually includes a controller, card reader, lock, door opening button, and management software. Access control systems are used in many office areas, warehouses, dangerous areas, prisons and other areas where outsiders are prohibited from entering. Common access control systems include: password recognition access control systems, credit card recognition access control systems, biometric access control systems, etc.

First. The benefits of using an access control system

1. Entrance and exit control and channel entry and exit control: prevent the entry and exit of people without cards and illegal card holders.

2. Statistics function: Statistic according to staff department, category and different time and place of entry and exit.

3. Illegal entry prevention function: The access control system can manage at least 100,000 black and white lists. If an unauthorized card or a card in the system blacklist is used, the system will refuse to open the door lock and automatically alarm through the booking procedure and device.

4. Prevent illegal time entry function: timetable can be set, such as certain time periods can be regarded as illegal time, card holders can not enter; you can check the entry and exit of each site and the entry and exit of personnel in each time period at any time.

5. Entry and exit records. Display the latest access control records, you can see the type, name, time and method of entering and exiting personnel. The bottom left shows the entry and exit of personnel, and counts the number of entry and exit of various types of personnel. At the bottom right, count the number of people entering and exiting each time period of the day.

6. Anti-theft function: When encountering criminals sneaking into the crime, the access control system will automatically close all access control after receiving the alarm.

7. Anti-theft function: The access control system is equipped with a rear power supply to prevent power failure.

8. Anti-implication function: The access control system can prevent the damage of one access control from affecting the normal operation of other access control.

9: Card embezzlement function: In the case of using the password keyboard, the cardholder must enter the password after swiping the card to perform dual identity authentication to prevent the adverse consequences caused by the loss of the card.

10. Convenient management. Electronic patrol, using the access control card reader as the patrol point, you can use the ready-made ID card as the patrol carrier, and you can upload the patrol records online in real time without configuring additional patrol equipment, and achieve online patrols. It improves the level of security and facilitates the management of patrol personnel.

11. Query function: you can query the records of any person, any time, and any door.

12. Double-door linkage function: The access control system can set permissions, and it is mandatory that when a door is open, all other doors cannot be opened. When a certain door is open, only certain doors can be opened or closed.

13. Fire alarm monitoring linkage function. In the event of a fire, the access control system can automatically open all electronic locks to allow people inside to escape at any time. Linkage with monitoring usually means that the monitoring system automatically records the situation when someone swipes the card (valid/invalid), and also records the situation when an alarm occurs in the access control system.

Second, the identification process of the access control system

1. The process of identifying permissions for conventional access control systems is divided into five steps:

2. Platform software editing authority;

3. The authority is issued to the access controller;

4. When swiping the card, the card number information is uploaded to the access controller;

5. The access controller judges the card swiping authority, the door is opened if it is legal, and the door is not opened if it is illegal;

6. Upload the card swiping event to the management platform;

Three. The difference between IC card and ID card

1. The ID card is a non-writable proximity card. Commonly used in life are attendance cards, access control cards, etc.

2. The IC card supports reading and writing functions. Commonly used are bus cards, employee cards, etc. (which can be used for consumption).

3. The security performance of IC card is much higher than that of ID card

Four. How does the card reader read the card information?

At present, the common types of IC cards and ID cards are radio frequency cards, which use radio frequency technology. When the card is close to the card reading area, the card will automatically send information. After the card reader reads and decodes the information, the card information is transmitted to the control host to determine the authority.

Five. What is the Wiegand Agreement?

The Wiegand protocol is an internationally unified communication protocol with many formats. In order to distinguish it from other manufacturers, the access control products use the private Wiegand 27 and Wiegand 35 protocols;

1. Usually a signal line can only be connected to one card reader; the normally closed (NC) type means that the relay is closed at normal times and disconnected after sensing the signal.

2. The theoretical transmission distance is 110 meters, and the actual transmission is about 80 meters;

Six, what is the RS485 protocol

RS485 protocol is also a common communication protocol, but it is not common among various manufacturers;

1. Multiple card readers can be connected in series through a signal bus (RVVP4*1.0) by hand in hand;

2. The transmission distance is relatively long. When the signal baud rate is 19200, the transmission distance can reach 600-800 meters;

Seven. What is "normally open and normally closed"

Normally open and normally closed refers to a switch state of the access control relay:

Normally open (NO) type means that the relay is open at ordinary times and closes after sensing the signal; normally closed (NC) type means that the relay is closed at normal times and opens after sensing the signal.

Eight, common electric locks for access control

There are generally three types of electric locks commonly used in access control systems:

1. Magnetic lock: It is closed when the power is turned on and unlocked when the power is turned off. It is a normally closed type, and is generally used for wooden doors, glass doors, and iron doors that open at 90°.

2. Electric mortise locks are classified into two-wire electric mortise locks, five-wire electric mortise locks, and eight-wire electric mortise locks depending on the wires.

1) Two-core function, there are two wires, red and black, red connects to power +12VDC and black connects to GND. Disconnect any wire, the lock retracts and the door opens. The two-wire electric lock has a relatively simple design. There is no single-chip control circuit, the lock body is easy to heat and burn hands, and the impact current is relatively large. It is a low-end electric mortise lock with a relatively low price.

2) Five-core function, there are two wires, red and black, red to power +12VDC and black to GND. There are also three COM NO NC wires, which are door sensor signal wires, which reflect the opening and closing status of the door. NO and NC form two pairs of signals opposite to COM (a group of closed signals and a group of open signals). Through the door sensor, according to the current open or closed state of the door, it outputs different switch signals to the access control controller to make judgments. For example, the illegal intrusion alarm of the access control, the door has not been closed for a long time and other functions rely on these signals to make judgments. If these functions are needed, the door sensor signal line can be left unconnected. The five-wire electric mortise lock adopts a single-chip microcomputer controller, with benign heating, with a delay control, and a door sensor signal output. It is a common type of electric lock with good cost performance.

3) Eight-core function, the principle is the same as the 5-wire electric mortise lock. In addition to the door sensor status output, the lock status output is also added. That is, the signal is different whether the lock is extended or not. Reflect the open and closed state of the door. It uses the door sensor to output different switch signals to the access controller for judgment according to the current open or closed state of the door.

4) The delay function of the electric bolt lock, this function will definitely be forgotten to debug for novices. The so-called with delay control means that there is a dial switch on the lock body, and the delay time of closing the door can be set. Usually can be set to 0 seconds, 2.5 seconds, 5 seconds, 9 seconds. Each manufacturer's lock has a slightly different delay in several gears.

3. Cathode lock: lock when power is off, and unlock when power is on. It belongs to the normally open type. The use scene is smaller than that of electric mortise locks. It is generally used for wooden doors and iron doors.

4. Electric control lock, silent lock, motor lock:

Disadvantages of electronically controlled locks: the impact current is large, which has a large impact on the stability of the system, and the noise is relatively large when the door is opened with a "pop". The installation is inconvenient, and professional welding equipment is often needed to spot welding to the iron door.

1. Pay attention during construction. The door opening delay cannot be long, and can only be set within 1 second. If it takes a long time, it may cause heating and damage to the electric control lock.

2. Another electric lock with a smaller sound. Instead of using the electromagnet principle, it drives a small motor to extend and retract the lock. Generally called motor lock or spiritual lock.

3. Electronically controlled locks, silent locks, and motor locks are mainly used for residential unit doors, second doors of bank savings offices and other occasions. You can also use the knob or key to open the door.

In recent years, due to the popularization of the Internet and smart mobile devices, the application of the Internet of Things in the field of access control has rapidly expanded. The concept of "smart home" has slowly entered people's vision. In the stage of diversified development, companies have spared no effort to develop products with core competitiveness. The access control system not only has the basic functions of controlling personnel access, but also Integrate with other systems, such as video surveillance, building intercom, WIFI probe, security prediction, emergency alarm and other functions. At the same time, in order to meet the needs of customers in different scenarios, major companies have begun to launch customized products and services. From the popular access control demand, it has gradually evolved into an access control solution for specific industries.

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