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Evacuation systems and power failure requirements....

Praesideo main components such as the network controller and power amplifiers have a primary input voltage of 90 to 264 Volts AC, 50-60Hz. In the event of primary mains failure a battery backup system should be used. Praesideo has secondary power supply input of 48Volts DC with an operating range of 45 to 56Volts DC.

Click on the links for more information:
Powerfail requirements for BS EN IEC 608849 >>
Praesideo battery back-up solutions from NTE >>
Powerfail requirements for BS EN IEC 608849

If the building is to be evacuated following primary power failure, a secondary power supply shall be provided. This shall be capable of operating the system in the emergency mode for a period equal to twice the evacuation time determined by the appropriate authority for the building. In any event, the secondary power supply shall be capable of powering the system for a minimum of 30 minutes.

If the building is not to be evacuated following failure of the principal power supply, the secondary power supply shall be capable of operating the system for at least 24 hours, or 6 hours if an emergency generator is available, and then powering the system in emergency mode for a minimum of 30 minutes. If a building remains unoccupied for several days, provission should be made to ensure that the voice alarm system is capable of operation in emergency mode for 30 minutes when the building is reoccupied.

Non-emergency functions within the system, such as background music, shall not operate from the secondary power supply if this will reduce the capacity for emergency operation. Praesideo has the facility from software version 1.1 for the BGM to be deactivated.

If batteries are used as a secondary power supply they shall be of the secondary type, complete with automatic charging facilities. Where lead-acid batteries are used they shall be of the valve-regulated type unless otherwise specified, and the charging system shall incorporate charging current compensation for changes in the ambient temperature, where this is necessary to achieve the specified battery life.

Batteries shall be used in accordance with the manufacturers recommendations in order to achieve their specified life, which shall not be less than 4 years. The end of life shall be taken as the time when the deterioration to less than 80% of the rated ampere-hour capacity (at the one-hour rate) has occurred.

Automatic charging shall ensure that the batteries are fully charged to 80% of their maximum rated capacity from the fully discharged state in a period of not more than 24 hours.

Adequate ventilation and protection against corrosion and dangers resulting from gases emitted by the batteries shall be provided.

Please note that the above requirements are the responsibility of the installer
Praesideo battery back-up solutions from NTE

NTE can design and supply a battery backup solution for Bosch Praesideo and other competitive evacuation systems.

The rectifier / charger unit is supplied with the following specification:

- On/Off indicator
- Output with double pole fused to suit the load
- Battery Voltmeter
- Charge Ammeter
- Charge fail indicator
- Single Pole Changeover - to indicate a mains or charge failure via a special contact
- 110/120 or 220/240 Volts AC mains single phase supply
- 54 Volt float potential
- Housed in a single or multiple cabinets depending on the load required
- Batteries supplied to BS6290 part 4 specification, 10 year life and flame retardant.


For more information about Bosch Praesideo voice evacuation systems and our battery back-up solutions please do not hesitate to contact us directly. Or if you know which part you are looking for, please complete our quotation request form and our Bosch team will respond to your enquiry immediately.


NTE Limited, 1 Faraday Road, Peterlee, Co Durham, SR8 5AP. Registered in England no. 3451873