Access card reader classification and how to choose

Door-disabled contactless IC card (inductive IC card) The card reader is an important part of the access control system and is the key device for the signal input of the access control system, which is related to the stability of the entire access control system. The card reader emits electromagnetic waves at a fixed frequency. The frequency is generally 13.56 MHz. When the proximity card enters the electromagnetic radiation range of the card reader, it will trigger the coil on the induction card, generate current and trigger the antenna on the proximity card to read the card. The device transmits a signal with card information, and the card reader converts the level signal into a digital serial number, which is transmitted to the local controller, and the local controller uploads the information to the upper controller, and finally uploads it to the access control server, and the access control The server compares the card number with the information in the database to obtain all the card information.

1 Introduction

Non-contact IC card with disabled door (inductive IC card) The card reader is an important part of the access control system. It is the key device for the signal input of the access control system. If the access control system is compared to a person, the card reader is like a human. eye. It is related to the stability of the entire access control system. If an access control system controller and electric lock are good, if the quality of the card reader is problematic, it will also cause the door to open, which will affect the acceptance and use of the project.

2, classification

The card reader is divided into a contact card reader, a contactless card reader, and the card reader is divided into a single interface card reader and a dual interface card reader and a multi-card seat contact type reading and writing interface from the readable card interface. Device.

From the interface point of view, the card reader mainly includes: parallel port reader, serial card reader, USB card reader, PCMICA card reader and IEEE 1394 card reader.

The card reader can be divided into two types according to the card reading protocol, one is a 485 card reader, and the other is a Wiegand card reader. Wiegand 26 and 34 protocols, these two protocols are conventional protocols.

The card reader can be divided into an IC card reader and an ID card reader from the card reading type. The IC card card reader is a non-contact IC card reading and writing device, which realizes connection with a PC through a USB interface, and is 5V alone. The power supply or keyboard Kou takes power, which supports access to all functions of the RF card. This series of equipment is used in access control, attendance, conference sign-in, highway, tourism, parking lot, bus fare, shopping mall consumption, membership system and card issuance system for various application systems.

The ID card reader is used to read the ID card. The card reader supports plug and play. It can be freely inserted and removed during use. No external power supply is required. The user does not need to load any driver. The windows system directly treats it as a HID device. keyboard. After the computer USB port is connected to the card reader, the card reader "drops" to start self-test and initialization, and then "drop" once successfully initialized, and enters the waiting for card-swapping state.

ID card readers are used for data entry, information inquiry, Internet cafe registration, book lending, conference sign-in, access control and other occasions.

Depending on whether you have a password, you can divide the password keyboard reader and the normal card reader.

Password keyboard reader: Some readers not only have wiegand26/34 card number output, but also have keyboard output, suitable for "card + password" access control occasions.

Common common card reader styles:

There are also long distance readers depending on the distance of the card reading:

3. How to choose

Note 1: Is it a domestic card reader or an imported card reader?

Imported card readers, the technology is relatively mature, the product repair rate is low, the design is more beautiful and durable. The disadvantages are: The price of the product is expensive, the service does not have a domestic card reader in time, and the imported induction card of the supporting brand must be used, and the imported induction card is also expensive. Unless the customer specifies the use of an imported brand of card reader, I recommend the use of domestic card readers, but must choose a domestic card reader with good quality reputation and good service. The appearance of domestic card readers is also closely following the international popular style. Imported card readers are 6-10 times the price of domestic card readers, and imported card prices are 10-20 times that of domestic cards. The core chips of domestic card readers and cards are all imported RF chips. The current production technology is also relatively mature, and the product quality is guaranteed.

Note 2: Is the ID card reader or IC card reader selected?

The ID card reader is a common name for a read-only contactless IC card, and the IC card reader is a collective name for a readable and writable contactless IC card. The performance price ratio and sensing distance of the ID card and the ID card reader are better than those of the IC card and the IC card reader. If it is only used for access control and attendance or parking card, it is recommended to use ID card reader and proximity card. If you need to be compatible with non-fixed spending cards, you can only use IC card readers and proximity cards. The ID card market is popular and the price is good is the EM card.

Note 3: Do not judge the quality of domestic card readers from the appearance.

Most domestic card readers use public molds or copy foreign readers. The mold is universal, and anyone can buy the outer casing, so even if the same type of card reader may be produced by different manufacturers, the service and quality are not the same. The engineer must have a detailed understanding of the card reader, not to distinguish it from the appearance and price. It is recommended that the contractor purchase the card reader from the place where the access controller is purchased. The general access controller manufacturer will either sell or produce a card reader with similar quality standards. So, how to judge the quality of a card reader? I believe that some domestic card readers use analog circuits instead of RF base station chips in pursuit of low cost of production. Such card readers have large operating currents, are prone to crashes or are damaged, Recommended. It is recommended that the card reader of the imported RF base station chip be better. Of course, it is also necessary to judge the use time and repair rate of the card reader of the manufacturer you purchased before, and the quality standard and word of mouth of the manufacturer. In addition, the card reader is a long-term use of the device, the circuit design must have a circuit to protect against the crash, this point should also be noted.

Note 4: Is it a sealed or unsealed card reader?

It is recommended to use a non-sealed card reader for the following reasons: Even if the glue is sealed, the buzzer is still exposed, and the water will damage the card reader. The material used for sealing is resin. Generally, the manual sealing agent is used to mix unevenly. The domestic resin material is cheap but the quality is not good. After long-term use, it will have conductivity, which makes the card reader run chaotic or Dead machine, imported resin is expensive. Domestic manufacturers are generally reluctant to adopt it. It costs more than a dozen pieces for each card reader. In addition, the sealant is not suitable for heat dissipation of the device, and it also affects the performance of the card reader. Therefore, Unless it is not necessary to use a sealed card reader in special occasions, it is sufficient to provide some waterproof protection for the card reader in special occasions.

4, working principle

The card reader emits electromagnetic waves at a fixed frequency, and the frequency is generally 13.56 MHz. When the proximity card enters the electromagnetic radiation range of the card reader, it will trigger the coil on the induction card, generate current and trigger the antenna on the card to the card reader. Transmitting a signal with card information, the card reader converts the level signal into a digital serial number, transmits it to the local controller, and the local controller uploads the information to the upper controller, and finally uploads it to the access control server, the access control server. The card number is compared with the information in the database to obtain all the card information.

Installation Precautions

1. Before powering up, you must confirm the voltage of the power supply (DC9V-DC15V) and the positive and negative poles of the power supply;

2. When using an external power supply, it is recommended to share the power ground (GND) with the controller power supply;

3. It is recommended to use a 8-core shielded multi-strand twisted pair cable for the card reader to controller line. (Three cores are reserved. If the card reader sound and light feedback legal card are not needed, the LED line may not be connected. The data lines D0 and D1 are better for twisting each other. The line cross-sectional area is recommended to be 0.22 square millimeters or more. It is recommended to be 80 meters. Connect the GND of the controller first, and add the thick or double strands to the reader to help improve the performance of the reader.