Surge Protection of Public Address Systems
Oscar DSouza
Sales & Marketing Manager | Datacenter, Telecom and IT infrastructure solution provider.
Why Protect?
The Public Address System is a set of devices used to disseminate information on local territory such as a building or community.
It is used for communication and providing information about activities or about imminent danger in the local area. In some countries, cities and municipalities are obliged to warn and inform their residents in the event of danger, environmental accidents, floods, fire, etc.
The general topology of a PAS may looks as follows. There are loudspeakers located around the locality. The signal is distributed over two-wire lines from the central unit and amplifier to the loudspeakers. In newer systems the signal can also be transmitted through wireless. A combination wired and wireless solutions may also be deployed.
Due to long lengths of the cable used in wired systems and the voltage losses on it, the signals are often modulated (amplified) to a voltage level of 100 V, on which amplifiers, speakers and protection devices must be also designed.
The modern solutions are central units with Ethernet line to PC connection and control, where the broadcast can be prepared in advance or started automatically at a scheduled time.
Because the public address system also serves as a part of safety system for reporting dangers in municipalities, it is very important to ensure its protection against surge, lightning strikes and to maintain the most reliable and durable operation.
What to Protect?
- Power supply of the PAS central control unit
- Local power supply protection for wireless loudspeaker units
- Data transmission lines to loudspeakers
- Coaxial lines from antenna for wireless data transfer
- Interfaces and communication lines
For more information visit our website www.dafnia.com or email us on [email protected]