How Does The Access Control System Work With The Fire Alarm System And Video Surveillance System?
Source: https://vedard.com/blog/access-control-system-work-with-the-fire-alarm-system-and-video-surveillance
Date: 2024/12/03
https://vedard.com/blog/access-control-system-work-with-the-fire-alarm-system-and-video-surveillance/Linkage between access control system and fire alarm system
In places with dense traffic, it is difficult to evacuate people in emergency situations such as fire alarms and terrorist attacks. This problem is particularly obvious after these places are equipped with access control systems. The “door gods” that usually ensure safety become a major obstacle to people’s escape. Therefore, the access control system must have a fire linkage function.
The signal output by the fire alarm system is usually a passive dry contact signal, and the access control system can be linked with it in two ways.
Direct power-off method for electric locks controlled by access control systems
The fire protection system can directly connect an external relay (it should be pointed out that when there is no fire alarm signal, the coil of the relay 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 normally open contact of the relay controls the on and off of the 220V power supply. When a fire alarm occurs, the relay will act in time to forcibly cut off the power supply of the electric lock of the access control system (mains power and backup power supply), so that the designated door can be automatically opened when the system is powered off. The advantage of this method is that it is simple to use, but the controller does not receive the alarm signal and does not save the corresponding records.
Access control system logic judgment linkage (indirect linkage)
The alarm signal of the fire alarm system communicates directly with the linkage expansion port of the access controller. This method can realize input functions including fire alarm signal input, glass breaker alarm signal input, etc., as well as sound and light alarm signal output, forced electric lock action output, etc. 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), and then control the designated electric lock to automatically open or close according to the pre-made linkage command, so as to facilitate the normal evacuation of personnel and achieve the purpose of escape.
In order to further emphasize the security of the passage and prevent someone from deliberately creating a false fire signal to automatically open the electric lock and cause an escape, the access control system can be set to a multi-channel fire alarm signal input authentication mode, that is, it can be set to open a designated door only when multiple fire alarm signals are received. If only a single alarm signal input is detected, no action command will be issued to the electric lock, but the electric lock can still be opened through the normal legal exit process.
Linkage between access control system and video surveillance system
Video surveillance is a relatively important subsystem in the security system and is also a necessary security device for any large public place. The access control system can cooperate with the monitoring 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. That is, the access control system output relay dry contact is used to provide 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 method is the most commonly used and the most basic in the past.
The second is the software method. The access controller with the function of supporting digital video server (encoder) can realize the dual data exchange function from the device protocol layer to the software database layer with the digital monitoring system at the same time. There is also a software method, that is, directly write the SDK of the video capture card in the NVR into the access control management system software, and associate it with the NVR device through the access control software function item. The above two software methods have their own advantages and disadvantages. The advantage of the former is that the system responds quickly and there is no delay. The disadvantage is that the video data must be saved in the local management host, and the capacity of the host hard disk is required to be high. The advantage of the latter is that the local management host does not need to save the video stream data. When needed, it only needs to call the data in the remote NVR. The disadvantage is that the associated video will have a delay of about 1-3 seconds, and the video before the abnormal situation at the channel cannot be called.
The access control system linked to video surveillance can mainly achieve the following three functions:
Video Recording
The access control system actions that can be associated include the removal of the controller or sub-device, illegal door opening, door opening timeout, forced door opening, invalid card, card swiping, button opening, disarming, arming, and various other alarm conditions. Once the controller detects the above signal, it will immediately start the video surveillance equipment to record the events on the channel site. The recording time can be freely set (generally including video recording before, during, and after the event), and the management host will reflect the video information in real time on the access control software monitoring interface. According to actual needs, the video recording data can be saved in the local management host or in a remote NVR.
Video capture
The same as the actions that can be associated with video recording, the difference is that this function only captures the event in video, and the captured image is the real-time information of the event.
Condition Monitoring
This function requires that the management host of the access control system must be turned on (the video surveillance system can be turned 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 site through the monitoring screen, and its function is similar to the monitoring function of NVR.
Access control system and intelligent building linkage
The linkage between the access control system and the smart building is mainly achieved through the relay on the access control controller or the system external relay, that is, all the switching actions in the building management system are equivalently converted into card swiping actions in the access control system. In essence, the card swiping action is associated with the relay on the access control controller or the external relay action, so that the relay outputs the switching signal to control or manage the various devices in the building system.
The linkage between the access control system and the building system is mainly reflected in the following three aspects:
Linkage with building intercom system
The linkage between the access control system and the intercom system is a parallel linkage. This linkage method mainly integrates the access control system into the building intercom door machine to realize the function of swiping card to enter the door. The mutual relationship between the two is manifested as pure hardware connectivity.
Moreover, there is basically no technical difficulty in this linkage. As long as there is reserved space in the intercom host to install the access control panel, the function of “intercom + access control” can be fully realized.
Elevator control linkage
The linkage control of the access control system and the elevator mainly realizes the following functions: making the public elevator a special elevator for the owner, enabling users to swipe the card to use the elevator (need to press the floor number key), and the elevator reaches the designated floor of the building after the user swipes the card (no need to press the floor number key), reducing elevator misoperation and idling, effectively reducing losses, reducing the burden of elevator maintenance, and saving maintenance costs. After the management personnel register, they issue a temporary access card or use the password set by the defendant cardholder to make the elevator reach the designated floor. The essence of its function is to convert the switch input of the elevator button into the switch input of the relay on the access control controller, and the action of swiping the card replaces the action of pressing the button.
Smart Energy Management
The powerful external linkage function of the access control management system can realize automatic energy management of the office environment. When working, the air conditioner and lighting equipment are automatically turned on by swiping the card, and when leaving get off work, the air conditioner and lighting equipment are automatically turned off by swiping the card 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. If necessary, other electrical equipment in the office can also be automatically linked and controlled. It can be set arbitrarily for 24 hours, automatically cycled, and the time period is accurate to the minute.
This linkage mode is mainly realized through the upper computer management software, the internal relay of the controller or the external relay. The principle is to use the switch output of the relay associated with the access control controller to control the AC contactor of the electrical equipment, and to control the electrical equipment by swiping cards, buttons or other methods.