The intrusion detection system is made up of three parts; Inputs, Areas and Process Groups. These are all required for the identification and processing of an intrusion event. For intrusion detection to work correctly, an input is programmed into an area and assigned a process group.

Security System Inputs (Zones)

A security systems input can be any switch, button or detector that is physically wired to a security controller or one of its expansion modules. The security controller monitors these inputs for state changes such as alarm (also known as unsealed), tamper or seal. A security systems input communicates changes to its current state by changing the resistance in the circuit. The set of resistors are called End of Line resistors. There are also logical inputs called system inputs, these inputs monitor a particular condition such as AC Fail, Cabinet Tamper and many others. Security System inputs are also programmed into an area and assigned a process group.

Wireless security inputs can also be used, including security motion detectors, door contacts and smoke detectors. These work in the same way as hard-wired inputs, with the addition of reporting when their battery is low. Inputs can be programmed into one or more areas; however, it is common that a security input only serves a single purpose.

Areas

An area is a collection of security inputs that are grouped in some way. An area commonly represents a physical location, such as all the security inputs in a board room. Alternatively, it could also represent all duress buttons in a building. When an area is armed (turned on), the controller will process the state changes of the security inputs, this processing is based on the process group assigned to an input within the area (for example: Alarms). A site can be represented by a single area covering the whole building, or can be broken up into numerous smaller areas if more granular control is required. An area can be programmed with an entry or exit delay to allow it to be armed or disarmed (turned on or off) without generating an alarm. The area is programmed with the siren and strobe outputs it can control and can be configured to auto-arm to ensure the security inputs are being monitored.

Process Groups

For a security input to be monitored by the system, the input needs to be programmed into an area and be assigned a process group. The process group defines how the security controller responds based on the input’s state changes and determines if any sirens need to be activated (including which tone to play) and if any communication with the security monitoring station is required. In normal operation, most process groups will only react if the area the input is assigned to is armed. However, if, for example, a detector input is tampered with then the process group will react regardless of the area’s arm state. An input can be isolated to temporarily disable the monitoring of state changes, this is commonly used when a detector is faulty or an input is in alarm whilst an area is being armed.

Access Control

The access control system combines access control modules, doors and card readers to restrict users from accessing certain areas within a building.

Doors

An access control door is any electronically controlled obstruction such as a door, auto door, roller door or boom gate that restricts a person or vehicle from entering a particular area. When a door is wired to the access control controller or other access control electronic modules, the electronic lock state of the door is determined by the access control controller. In some cases, the door may be configured to automatically unlock during normal working hours and relock after hours. Users can also unlock doors by providing a credential such as a card or a PIN number at a reader. Access to a door also requires that the user has the appropriate permissions to enter/exit the door. The access control controller is capable of monitoring the status of door inputs such as a door reed or tongue sense to determine if a door is open or closed, or if the lock is functioning correctly. This allows the access control controller to know if the door has been forced open or has been held open too long.

Readers

The card reader is an access point that a security user interacts with to unlock a door. Depending on the door there may be a reader on either side or on both sides of the door. A door with only a single reader is restricting access from only one side of the door and usually, can be exited by using the door handle or a Request to Exit (REX) button. Access Control Doors with readers on both sides are generally used when knowledge of a user’s location is important or both the inside and the outside of the door are restricted, such as airlocks in a hospital or in car parks. The access control system supports a range of reader technologies such as Inner Range SIFER, Wiegand and keypad readers.

DOTL

DOTL or Door Open Too Long (also known as Door Held) is a state where a door has been unlocked and opened, then not securely closed within a particular period of time. DOTL is used to ensure that users close the door properly after use. Prior to entering the DOTL state, a local audible warning tone can be generated to draw a person’s attention to the open door, allowing them some time to close the door securely. If the warning time expires and the DOTL state occurs, it will result in a DOTL input going into alarm. This can be reported to a monitoring station to ensure someone knows the door has not been shut properly, or that there is a fault with the door or the lock.

Door Forced

The Door Forced state occurs when a security door is locked and secured, but is then opened. The Access Control Controller uses the door reed switch and/or the tongue sense to determine if a door has been opened/unsecured. If this occurs when the door should be locked, the controller sets a Door Forced input into the alarm state which can be reported to the monitoring station. This behavior means the door forced state can be monitored directly, without needing to temporarily isolate (also known as shunt or bypass) the door inputs for standard day to day activity.

Area Disarm on Entry

When a security user presents their access card at a reader to enter a door that has an armed area on the other side, if the user security has permissions to access the door AND to disarm the area, then the area can be programmed to automatically disarm. This is used to reduce the number of steps needed to enter a door as the user does not need to disarm the area from a keypad after entry.

Restricting User Access

When a security user presents their access card at a reader to enter a door that has an armed area on the other side, if the security user only has permission to access the door and NOT to disarm the area then user will be denied access to the door. This is commonly used when certain people, such as a supervisor, needs to enter the area before others. The supervisor will be the only user provided the permission to disarm the area. Once the inside area is disarmed, any user with permission to access the door can present their access card at the reader and unlock it.

Security User

A security user is any person that will interact with the Intruder Detection and Access Control system via a keypad, access control reader or the web interface. Every user will have one or more credentials and some permissions.

Credentials

To identify which user is interacting with the system each user requires unique credentials. Credentials include a security PIN for interacting with an LCD terminal, cards for accessing doors and may include a username and password for access to the web interface or software.

Security Permissions

To identify which user is interacting with the system each user requires unique security credentials. Security Credentials include a security PIN for interacting with an LCD terminal, cards for accessing doors and may include a username and password for access to the web interface or software.

Security Area Permissions

In addition to the flexibility of the What and When fields for permissions, the security area can provide specific control options to allow the security user to only arm or disarm the area. The arm only control of a security area can be provided to security users to ensure that if they were the last person onsite, they could arm the entire building.

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