Today, the need to equip a residential building or public building with an automatic fire alarm system is no longer in doubt. Such installations consist of a whole complex of devices and devices for various purposes, the main task of which is to detect a fire at an early stage of a fire. The core of such a system is the fire alarm control panel, abbreviated PPKP.
Main functions
By definition, the control panel is a device for receiving signals from detectors, their power supply, notifying personnel through sound and light annunciators, transmitting notifications to the monitoring station, and generating a start pulse for control devices. Thus, the main functions of the control panel:
- arming and disarming;
- reception and analysis of signals from sensors;
- loop condition monitoring;
- power supply of current-consuming detectors;
- light and sound warning of operational personnel;
- transmitting notifications of the installation status to the central monitoring console ;
- launching devices or control circuits for engineering equipment, fire fighting, warning.
Classification
The control panel is classified according to the following criteria:
- information capacity;
- informational content;
- method for monitoring detectors;
- type of communication channels.
Information capacity is characterized by the number of fire loops that the device can service. On this basis, devices are divided into:
- up to 8 loops - low capacity;
- from 9 to 64 loops - medium capacity;
- more than 64 loops - large capacity.
Informativeness characterizes the number of notifications issued by the device, such as "Fire", "Caution", "Fault" and others. Devices can be:
- low information content - up to 8 notifications;
- average information content - from 9 to 16 notifications;
- very informative - over 16 notifications.
By the method of control, address and analog systems are distinguished. In address systems, each detector is equipped with a microprocessor that reports its status to the controller via a digital communication line. In an analog system, the sensor, depending on the state, changes its resistance, the control panel records this change.
By types of communication channels, automatic fire alarm systems are divided into wired and radio channels.
Analog Radial Systems
Traditionally, control panels with analog radial loops are used. In each loop of such a device several detectors can be installed that protect different rooms. When any detector is triggered, the loop resistance drops, and the control panel issues an alarm. At the same time, it is impossible to determine the exact place of ignition; the state of the entire loop is fixed. Therefore, the number of detectors in the loop is limited to 15-20 pcs., And the number of rooms protected by one loop is 10 (within the same floor). The status of each loop is indicated by the color of the glow and the blinking of the control panel LED.
Such control panels are issued in the form of complete modules that perform all the functions provided for by the standards. The main advantage of such devices is the ease of installation, configuration and operation. To ensure uninterrupted power supply, they are equipped with built-in redundant power supplies with battery.
As a rule, devices with radial loops are made by a ruler, depending on the information capacity. For example, the popular Granit control panel is available in 2, 3, 4, 5, 8, 12, 16, 24 loops. Such a model range allows the use of devices at objects of various sizes.
Address Alarm
Address systems are gradually replacing analog ones, displacing them not only at large, but at medium and small objects. The main difference between such a system is the redistribution of signal processing functions. Measurement of fire factors (temperature, smoke, flame brightness), their digitization and analysis are carried out in a fire detector. For this, the address sensors are equipped with a microprocessor operating according to a certain algorithm. The processor not only controls the fire factor, but also analyzes its condition, for example, dust content, temperature, etc.
The control panel communicates with the detectors via a digital communication line using noise-protected protocols, which virtually eliminates the possibility of error. In the digital line, each detector is assigned its own unique address, allowing you to accurately determine the location of the triggered device. The presence of a microprocessor allows you to individually configure each sensor, taking into account its dust content, conditions in the protected room, and operation mode.
Using digital infrastructure allows you to design expandable and geographically spaced structures of almost unlimited scale. For digital systems, it is important that the equipment line of one manufacturer contains the full range of necessary devices. For example, the Bolid fire alarm system includes detectors, controllers, control panels, power supplies, and other equipment.
Control lines
To control the notification, engineering equipment, transmitting notifications to the monitoring station, control panels are equipped with a set of relay contacts. As a rule, their number is from three to five in non-addressable control panels. The increase in control circuits is carried out by installing additional relay boards. In address systems, an increase in the number of outputs is carried out by connecting additional modules and expands the possibilities that a fire alarm solves.
"Bolid" produces a line of signal-start-up and control-start-up blocks, allowing you to control any engineering systems. To control the notification, block general ventilation, start fire extinguishing, etc., output contacts must be used to ensure line monitoring for open and short circuits. The presence of such relay outputs is separately recorded in the device passport.
Burglar and Fire Alarm
Security devices in their functions are similar to firefighters. Often a fire alarm is combined with a burglar alarm. To control such a system, a security control and fire control device is used. The difference between such a device is the versatility of its loops: they allow you to connect both fire detectors and security.
When programming, each loop is assigned a specific protection tactic: fire smoke, security, alarm, etc. Most modern devices are equipped with just such universal loops. For example, the popular reception-control device “Signal-20” has 20 universal loops.
Power supply
An automatic fire alarm is a system that must operate continuously, 365 days a year. Therefore, the control and fire alarm device is provided with electricity in the first category of reliability. Not everywhere, electrical networks provide this category, therefore, redundant power sources are used to power fire protection devices. They are installed batteries that support the system in the absence of main power. The battery capacity should be sufficient for battery life for 24 hours in standby mode and 1 hour in alarm mode.