Electronic sirens



Basic characteristics

PAVIAN electronic sirens represent the highest level of electronic systems offered by Telegrafia. These are modular electronic devices primarily designed for establishing large and complex warning systems requiring sophisticated control and efficient siren status monitoring. They are also used as locally controlled devices where required due to a more complex interface with the environment or when a sophisticated algorithm for reacting to external signals is desired. Based on information gained from the environment, these systems are capable of reacting on the basis of modifiable algorithms and, in addition to acoustic warning system initiation; they are also capable of controlling external devices. For instance a certain value of a harmful substance as read by a sensor connected directly to the siren’s input can be of such a character that the siren activates a beacon or text message in addition to acoustic warning system initiation.

PAVIAN electronic systems not only represent a sophisticated terminal acoustic element with different control methods but they also have interfaces and basic options for monitoring and controlling implemented systems. Since monitoring systems often form a part of warning systems, the application of a PAVIAN type siren enables cost savings with regards to parallel establishment of these separate systems. It is possible to form arrangements with outputs from 300 W to 4,500 W.

Main functions and properties

  • Sound recording playback from digital memory (SD card) in WAW, MP3 format;
  • Playback from combinations of different sound recordings;
  • Ability to connect local audio signal inputs, including a local microphone or other local signal sources;
  • Ability to connect to remote audio signal sources – Dispatch centre, VHF radio, radio station, phone …;
  • Galvanically separate class “D” amplifiers with up to 90% power efficiency;
  • Enhanced automatic testing routines, including so-called “silent” siren tests, complete functionality tests;
  • Ability to automatically switch over to a backup amplifier;
  • Different local activation options;
  • Different remote activation options;
  • Automatic broadcasting of emergency status announcements;
  • Storage of all the important events related to siren activities in the internal memory;
  • Intelligent battery recharging, charging current optimizing based on modern algorithms recommended by manufactures to prolong battery life;
  • 8 programmable digital/analogue inputs;
  • 8 programmable digital outputs;
  • 2 RS232 ports;
  • Ability to program different reactions on the basis of different inputs;
  • Power supply from maintenance-free batteries; ,
  • A stainless steel box;
  • Durable sound baffles made of a lightweight aluminium alloy;

Control methods

PAVIAN type electronic sirens are primarily designed for complex warning systems requiring sophisticated control and efficient siren status monitoring. They are also used as locally controlled devices, if required due to a more complex interface with the environment or in case that a more sophisticated algorithm for reacting to external signals is desired. For this purpose these sirens can be equipped with both control modules manufactured by Telegrafia and connected directly to Telebus®, an internal siren bus, and general interfaces mainly designed for use by partner companies for systems integration.

Pavian - electronic part

All whole electronics of PAVIAN siren are integrated in a box made of stainless steel. The box is protected against unauthorized access or siren control by two locks and a door sensor connected to the control unit. For more demanding applications it is possible to deliver special boxes with an additional cover to protect against adverse weather conditions.

The core of the siren consists of a control module, amplifier modules (Amplifier output is 2 x 150W), a power supply unit and a battery charger. The electronics of the siren are fed from two 12V maintenance-free batteries, which are continuously recharged from a 230/120V circuit. Battery capacity depends on the number of amplifiers used, i.e. from siren output. As a standard, the batteries are capable of ensuring 72 hour siren operation following a power failure (weeks in a stand-by mode). Thanks to the optimized electric power consumption solar-cell based operation is also available.

Auxiliary modules used mainly for siren-environment communication are also located in the box. Some of the auxiliary modules are manufactured directly by Telegrafia, some by the company’s partners or by third parties.

Pavian - acoustic part

The acoustic radiator consists of a “horn” type loudspeaker and hyperbolic sound baffle. Both the loudspeaker and the sound baffle are optimized in terms of spreading typical acoustic warning signals simulating the horn sounds of conventional motor-driven rotary sirens. The highest acoustic pressure is achieved in the frequency range of these signals, thus maximizing the siren’s coverage.

Usually two radiators are mounted on a steel pole. However, their arrangement is optional, which enables various radiation characteristics to be achieved, from almost circular, through elliptic up to directional characteristics.

The sound baffles are made of a special aluminium alloy, so that their durability is maximized and their weight minimized. They are virtually always installed outside on a high spot and are exposed directly to the effects of weather (sun, rain, snow, wind...) and very often to insects (wasps, bees...) as well. Experience from using plastic sound baffles shows that their life cycle in such severe siren usage conditions is very short and the cost of their maintenance and replacement highly exceeds that for aluminium baffles. Moreover, horn loudspeakers are designed to have the maximum resistance and output possible.

Telegrafia has developed several types of roof poles for installing sound baffles on different types of roofs and columns. These poles are designed in such a manner that their assembly, sound baffle included, is as easy as possible and at the same time all strength requirements related to their standard use are met. All pole types have been structurally evaluated and approved