How does the access control system link up with fire alarm and surveillance
1. The linkage between the access control system and the fire alarm system
In places with a large flow of people, it is more difficult to evacuate people in emergency situations such as fire alarms and terrorist attacks. This problem is especially obvious after the access control system is installed in these places. It has become a major obstacle for people to escape. Therefore, the access control system must have the function of fire and fire linkage.
The signal output by the fire alarm system is usually a passive dry contact signal, and the linkage between the access control system and it can be realized in two ways.
First, directly power off the electric lock controlled by the access control system.
The fire-fighting system can be directly connected to the relay (it should be pointed out that when the relay does not have a fire alarm signal, the coil should be in a power-off state, so as to extend the life of the relay) to control the power supply of the electric lock of the access control system, that is, the relay is normally open The contact controls the 220V power on and off. When a fire alarm occurs, the relay will act in time to forcibly power off the access control system’s electric lock power supply (mains and backup power) so that the designated door can be opened automatically when the system is powered off . The advantage of this method is that it is simple to use, but the controller does not have access to the alarm signal, nor does it save the corresponding records.
Second, the logical judgment linkage of the access control system (indirect linkage).
The alarm signal of the fire alarm system directly communicates with the linkage expansion port of the access controller. This method can realize the input functions including the fire alarm signal input, the glass breaker alarm signal input, and the sound and light alarm signal output, and the forced electric lock Action output and other functions. In the event of a fire, the access controller will receive the fire alarm signal transmitted by the fire alarm system in the form of relay dry contacts (the fire system actively sends the signal, and the access control system passively receives and executes the control), so as to control the designated according to the prefabricated linkage command The electric lock is automatically opened or closed to facilitate the normal evacuation of personnel and achieve the purpose of escape. At the same time, some doors are closed to prevent the spread of fireworks.
In order to further emphasize the safety of the passage and prevent someone from deliberately creating false fire signals to automatically open the electric locks and causing escape accidents, the access control system can be set to multi-channel fire alarm signal input authentication mode, which can be set to receive multi-channel fire protection A designated door (such as fire access doors on each floor) is opened when an alarm signal is issued. If only a single alarm signal input is detected, no action command will be issued to the electric lock, but the normal legal exit process can still be The electric lock is opened.
2. Linkage of access control system and video surveillance system
Video surveillance is an important subsystem in the security system, and it is also a necessary security equipment for any large-scale public place. The access control system can cooperate with the surveillance system camera, matrix or NVR to realize the image capture and monitoring functions of the controlled access control points.
The linkage between the access control system and the video surveillance system can be achieved in two ways:
The first is the hardware method, which uses the dry contact of the access control system output relay to the matrix alarm input module of the monitoring system and the alarm input terminal of the NVR to realize the image capture and monitoring function of the controlled door or related parts. This type of linkage is the most commonly used and the most basic in the past.
The second is the software method, which has an access controller that supports the function of a digital video server (encoder), and simultaneously realizes the dual data exchange function from the equipment protocol layer to the software database layer with the digital monitoring system. There is also a software method, that is, directly write the access control management system software into the SDK of the video capture card in the NVR, and associate it with the NVR device through the access control software software function item. The above two software methods have their own advantages and disadvantages. The former has the advantage of fast system response and no delay. The disadvantage is that the video data must be stored in the local management host, which requires a higher capacity for the host’s hard disk. The advantage of the latter is that the local management host does not need to save the video stream data, but only call the data in the remote NVR when needed. The disadvantage is that the associated video will have a delay of about 1-3 seconds, and it cannot deal with abnormal conditions at the channel. The previous video is called.
The video surveillance of the access control system can achieve the following three functions:
1. Video recording
The access control system actions that it can be associated with include the removal of the controller or sub-devices, illegal door opening, door opening timeout, coercion to open the door, invalid card, card opening, button opening, disarming, arming, various other alarm conditions, etc. If the above signal is detected, it will immediately start the video surveillance equipment to record the event at the channel site. The recording time can be set freely (usually including video recording before, during and after the event), and the management host will be real-time Reflect the recorded information on the monitoring interface of the access control software. According to actual needs, the video recording data can be stored in the local management host or in a remote NVR.
2. Video capture
The same as the actions that can be associated with video recording, the difference is that this function item only captures the video of the event and the captured image is the real-time information of the event.
3. Status monitoring
This function requires that the management host of the access control system must be in the on state (the video surveillance system can be on or off according to the actual function of the access control product), and the real-time monitoring screen of the access control software is consistent with the screen at each channel. The operator can synchronously observe the status of the channel scene through the monitoring screen, and its function is similar to the monitoring function of the NVR.
Three, access control system and intelligent building linkage
The linkage between the access control system and the intelligent building is mainly realized through the relay on the access control controller or the external relay of the system, that is, all the digital actions in the building management system are equivalently converted into the card swiping actions in the access control system. The essence is The card swiping action is associated with the relay or external relay action on the access controller, so that the relay outputs a digital signal to control or manage various equipment in the building system.
The linkage between the access control system and the building system is mainly reflected in the following three aspects:
1. Linkage with building intercom system
The linkage between the access control system and the intercom system is a parallel linkage. This linkage method is mainly to integrate the access control system into the building intercom door machine to realize the function of swiping the card to enter the door. The mutual correlation between the two is shown as a pure hardware connection. .
And this linkage basically does not have any technical difficulty, as long as there is a reserved space in the intercom host to install the access control panel, the “intercom + access control” function can be fully realized.
2. Elevator control linkage
The access control system and the elevator linkage control mainly realize the following functions: make the public elevator a dedicated elevator for the owner, enable users to swipe the card to use the elevator (need to press the floor number key), and after the user swipes the card, the elevator reaches the designated level of the building (no need to press the floor number key), reduce elevator misoperation and idling, effectively reduce loss, reduce elevator maintenance burden, and save maintenance costs. After registration, the administrator will issue a temporary access card or use the password set by the defendant to make the elevator reach the designated floor. The essence of its function is to convert the switch input of the elevator buttons to the switch of the relay on the access controller. For quantity input, the action of swiping the card replaces the action of pressing the key.
3. Intelligent energy management
Through the powerful external linkage function of the access control management system, automatic energy management of the office environment can be realized. When going to work, the air conditioner and lighting equipment are automatically turned on by swiping the card action, and the air conditioning and lighting equipment are automatically turned off by the swiping card action at the end of work to save energy. At night, the building landscape lighting equipment is automatically turned on by the relevant operation of the access control system, and automatically turned off in the morning, etc. If needed, it can also automatically control other electrical equipment in the office. It can be set at will for 24 hours, automatically cycle, and the time period is accurate to the minute.
The realization of this linkage mode is mainly realized through the host computer management software, the internal relay of the controller or the external relay. The principle is also to use the switch output of the relay associated with the access controller to control the AC contactor of the electrical equipment. Buttons or other ways to achieve control of electrical equipment.