Fire alarm panel
A Fire Alarm Panel or Fire Alarm Control Panel, normally referred to as a Panel within the fire industry is a central control device for detecting, reporting and acting on occurrences of fires within a building. There are two types of panel: conventional panels, and analogue addressable panels.
In a conventional panel, fire detection devices including, but not limited to smoke detectors and manual call points (MCP's) are joined up with a number connected to each circuit. When a device on the circuit is activated, the panel recognises an alarm on that circuit and could be set up to take a number of actions including directly calling the fire brigade via an alarm transportation system (ATS).
An analogue panel is a more modern type of panel and is a lot more flexible. An analogue panel has a number of loops, which can have connected a number of devices each with its own address. There is no standard protocol as such, and number of proprietary solutions exist. Loop devices have traditionally been able to have 99 or 100 devices connected, but more recent protocols allow a lot more. This is usually overcome by having a multiple number of loops on one system. Devices on an analogue panel
Fire panels are included as a necessary requirement in the construction of buildings ( Building code ) in most countries.
There are two main types of fire alarm panels. Conventional panels, and analogue addressable panels.
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Conventional Panels
Conventional panels have been around ever since electronics became small enough to make them viable. They are no longer used frequently in large buildings, but are still used in smaller, or less important buildings such as schools.
Conventional panels usually have a small number of circuits, each circuit covering a zone within the building. A small map of the building is often placed near the main entrance with the defined zones drawn up, and LED's indicating whether a particular circuit/zone has been activated. Another common method is to have the different zones listed in a column, with an LED to the left of each zone name.
The main drawback with conventional panels is that one cannot tell which device has been activated within a circuit. The fire may be in one small room, but as far as the brigade can tell, a fire could exist anywhere within a zone.
Analogue Addressable Panels
Analogue panels are usually much more advanced than their conventional counterparts, with a higher degree of programming flexibility and single point detection.
Loops
Panels usually have a number of loops within the range of 2 to 20 loops. At the present time, 4 or 6 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 devices include
- Smoke detectors
- Manual call points
- Responders
- Sprinkler inputs
- Switches
- Flow control
- Pressure
- Isolate
- 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 system's
- Turning on alarms or bells
- Shutting down industrial equipment
Et cetera.
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 section, 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 detector 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 only ring the fire brigade if more than one device has activated. It can also be used for crude 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 usually 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. This is known to be very clunky and is disliked by many developers.
More recently, some panels are being networked with standard Ethernet, but this is not yet very common. The fruit of choice for most organisations is 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
Most installations do not have special monitoring facilities for the state of the fire systems installed. They have been around for a long time (? years), but have only recently started to come into demand. The distribution is now well established in the United States, but less so in Australia and the United Kingdom (rest of the world someone?).
Monitoring systems have typically consisted of a computer connected to a panel, or a network, with a drill-down map of the building. The majority of these are badly outdated in the United States because of the difficulty of passing new systems through the approval process. The system is less clogged in Australia and New Zealand where some newer systems have started to come through (although still developed in the United States).
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.