jotron MPA 1600, Руководство пользователя и инструкция по установке

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User and Installation Manual
Compact MPA
4 PERFORMANCE
4.1 GENERAL ALARM
The General Alarm tone in the Compact MPA system consists of seven short followed by one long tone burst. Each short tone
has approximately 1 sec. duration, each pause between tones approximately 1 sec. and the long tone has 7 sec. duration. The
alarm signal sequence is continuously repeated. The standard alarm tone is a 1000 Hz sinusoidal tone.
The General alarm tone can be adjusted by means of loading different configuration data. Frequencies between 200 and
2500 Hz can be selected along with triangular or sinusoidal curve form. The configuration changes require a special adminis-
trative tool and are unavailable during normal operation.
4.2 FEEDBACK COUNTERMEASURES
In the Compact MPA system there are three different countermeasures available in order to avoid audible feedback and
disturbance during announcements.
The MPA 1601 Control Unit is equipped with either a gooseneck or handheld microphone with close-talk characteristics with
excellent background noise suppression capability. It is equipped with relays for disconnecting loudspeakers in the close
proximity when activated.
Each audio interface can be programmed to be of a recording type. The message is temporarily recorded and is automatically
played back when the announcement is terminated.
4.3 REDUNDANCY
In a PA/GA system like the Compact MPA the design and the installation must be carried out in a way that the damage of one
single failure shall be minimized as far as possible. To achieve full redundancy using the Compact MPA system, follow these
measures:
4.3.1 CENTRAL EQUIPMENT
The Compact MPA cabinet must be duplicated and physically separated in different fire zones – System A and B. Ref. picture
in chapter 1.
The A and B central equipment are connected together with a synchronisation link to coordinate alarm tone generation and
other timing-related functionality. If this synchronisation link is somehow broken or damaged the systems will work individu-
ally.
The MPA 1601 Control Unit and MPA 1603 Alarm Panel are equipped with a duplicated interface for connection to both sys-
tems (A and B). The connection status is displayed in the System A / B led indicator of the MPA 1601.
4.3.2 LOUDSPEAKER DISTRBUTION NETWORK
The loudspeaker distribution network must be duplicated and routed separately in different cable ducts and as physically
separated as possible.
All public areas shall be covered equally from both loudspeaker distribution network.
All cabins shall be supplied with PA/GA loudspeakers. Minimum requirement is that neighbouring cabins shall be supplied
from different loudspeaker distribution network.
4.3.3 ALARM PANEL
In order to have a required redundancy and availability to the General alarm, the minimum amount of MPA 1603 Alarm Pan-
els is two. One shall always be placed on the Navigation Bridge. At least one more shall be placed in another strategic place
as an alternative activation position.
4.3.4 CONTROL UNIT
In order to have a required redundancy and availability to the Emergency PA, the minimum amount of MPA 1601 Control
Units is two. One shall always be placed on the Navigation Bridge. At least one more shall be placed in another strategic place
as an alternative activation position. Additional units should be placed where it is deemed necessary.