How does the card access control system release the line?
From the controller to the management of the computer, there is a signal line, its transmission protocol is mostly RS485, when the distance may be near RS232 (to reduce a RS232 / RS485 converter), when the required transmission rate is fast, Then use TCP / IP protocol, the use of Ethernet transmission. These three protocols can use twisted pair, only in the RS485 or RS232 transmission, basically in the access controller product manual are required to use shielded wire. In order to avoid electromagnetic interference, this signal line should be shielded twisted pair.
There are three sets of signal lines in the controller, connected to the card reader (4 ~ 9 core), the lock in the lock state sensor (2 core) and out button (2 core). This three-way signal line can be replaced by twisted pair in integrated wiring.
Access control system with the majority of electric locks are 12V DC power supply. In the moment of electric lock breaking, due to the role of electric lock line package (solenoid coil), the power line will produce a strong current, it is easy to cause power fluctuations, and this power fluctuations on the stability of the controller is extremely Adverse, so the relatively high reliability requirements of the access control system, the controller and the electric lock, respectively, the use of different power modules, that is, 220V AC power supply to the controller, the use of two 12V DC power modules are rectified / Respectively, supply the electric lock and the controller.
Power line access control system power supply mostly from the engine room UPS, in order to avoid sudden power outage caused by open the door when the malfunction. The power line is usually in the 220V AC transfer mode, the purpose is to reduce the voltage drop on the power line. In the controller, equipped with a regulated power supply, the AC 220V power supply into a DC 12V power supply, respectively, supply controller and electric lock.
