Articles
Fire alarm control panel
A fire alarm control panel, also referred to as a fire alarm panel or FACP, normally referred to as a panel within the active fire protection industry, is a central control device for detecting, reporting and acting on occurrences of fires within a building. It is an active fire protection item that is subject to stringent bounding. There are two types of panels: conventional panels, and analogue addressable panels.
In a conventional panel, fire detection devices including, but not limited to smoke detectors, heat detectors and manual call points or manual pull stations are joined up with a number connected to each circuit. When a device on the circuit is activated, the panel recognizes an alarm on that circuit and could be set up to take a number of actions including directly calling the fire department via an alarm transportation system (ATS).
An addressable panel is a more modern type of panel, and has greater flexibility than a conventional panel. An addressable panel has a number of loops, where a number of devices are able to be connected, each with its own address. There is no standard protocol as such, and thus a number of proprietary solutions exist. Loop devices have traditionally been able to have 99 or 100 devices connected, but more recent protocols allow many more. This is usually overcome by having multiple loops on one system.
Fire panels are required in the building code for new structures in most countries.
Loops
Panels usually have a number of loops within the range of two to 20 loops. At the present time, four or six loop panels are the most common.
Each loop can have a number of devices connected to it. Each device has its own address, and so the panel knows the state of each individual device connected to it. Common addressable input (initiating) devices include
* Smoke detectors
* Manual call points or Manual pull stations
* Responders
* Fire sprinkler inputs
* Switches
o Flow control
o Pressure
o Isolate
o Standard switches
Addressable output devices are known as relays and include:
* (Warning System/Bell) Relays
* Door Holder Relays
* Auxiliary (Control Function) Relays
Relays are used to control a variety of functions such as:
* Switching fans on or off
* Closing/opening doors
* Activating Fire suppression systems
* Activating notification appliances
* Shutting down industrial equipment
Since their inception, loops have generally been able to handle 99 devices. More recently however, new protocols have been designed that allow 256 devices on each loop.
Mapping
Also known as "Cause and Effect" or "Programming", mapping is the process of activating outputs depending on which inputs have been activated. Traditionally, when an input device is activated, a certain output device (or relay) is activated. As time has progressed, more and more advanced techniques have become available, often with large variations in style between different companies.
Zones
Zones are usually made by dividing a building into different sections, and placing each device in the building in a different zone.
Groups
Groups are used to group two or more relays. They are used to shorten programming time by allowing several detectors to link to any particular group which then maps to a group of relays.
Boolean logic
This is the part of a fire panel that has the largest variation between different panels. It allows a panel to be programmed to implement fairly complex inputs. For instance, a panel could be programmed to notify the fire department only if more than one device has activated. It can also be used for staged evacuation procedures in conjunction with timers.
Networking
Networking is the idea of connecting several panels together to form a system. Inputs on one panel can activate outputs on another. It is often used in situations where one panel is not large enough, or in multiple-building situations.
Although quasi-standards exist that allow panels from different manufacturers to be networked with each other, they are not in favour with a lot of companies (so they are not de-facto at all). One of the most common of these is named BACnet which is used for various type of industrial networks.
More recently, some panels are being networked with standard Ethernet, but this is not yet very common. Most organizations choose to create their own proprietary protocol, which has the added benefit of allowing them to do anything they like, allowing the technology to progress further.
Networking is also good for allowing a number of different panels to be monitored by one graphical monitoring system.
Monitoring
In nearly every state in the USA, the International Building Code requires fire alarm and sprinkler systems to be monitored by an approved supervising station.
A fire alarm system consists of a computer-based control connected to a central station. The majority of fire alarm systems installed in the USA are monitored by a UL(r) listed or FM Global(r) approved supervising station.
These systems will generally have a top level map of the entire site, with various building levels displayed. The user (most likely a security guard) can progress through the different stages. From top level site ? building plan ? floor plan ? zone plan, or however else the building's security system is organised.
A lot of these systems have touch screens, but most users tend to prefer a mouse (and a normal monitor), as it is quite easy for a touch screen to become misaligned and for mistakes to be made. With the advent of the optical mouse, this is now a very viable option.