Board Functions; Day/Night" Function; Monitor" Function (Audio Monitoring); Ovl" Alarm - rcf RB 3300 Manual De Uso

BOARD FUNCTIONS

"DAY/NIGHT" FUNCTION

This function can be used when the RB 3300 back-amplifier board (A.C.U.) is equipped with the optional LB 3340 DIGITAL ALC board, making
it possible to attenuate the sound level during the nighttime hours. The level of attenuation can be chosen among 16 values during installa-
tion of the LB 3340 board, and is applied to all the audio zones controlled by the RB 3300 board. Special menus on the CP 3100 control unit
are used for activating the "DAY/NIGHT" function and defining the time band to be affected.

"MONITOR" FUNCTION (audio monitoring)

This function makes it possible to use the loudspeaker of the CP 3100 control unit to listen to the monitor signal of the RB 3300 back-ampli-
fier board (A.C.U.) related to the speaker output of the amplifier under its control. A dedicated menu on the CP 3100 control unit is used for
setting the monitor function. The command for monitoring is transmitted via the serial line.
IMPORTANT NOTES
• When an A.C.U. is disactivated, it is no longer possible to listen to its monitor signal; this is to permit listening to the monitor signals of
the other A.C.U.s also in the event that it is no longer possible to activate that unit again.
• Only one A.C.U. can be monitored at a time.

"OVL" ALARM

The RB 3300 board is equipped with an input that can be connected to an auxiliary contact of the amplifier being controlled, which makes it
possible to pick up alarm signals. The type of alarm picked up thus depends on the specific amplifier used, and can be, for example, related
to the intervention of one of the protection circuits, or to abnormal amplifier operation (e.g. operation in overload). If the alarm condition per-
sists for at least 10 seconds, the RB 3300 activates the alarm indication on the CP 3100 control unit via the serial line. By programming the
control unit in a certain way, when the amplifier goes into alarm status, a backup amplifier will be automatically activated in its place.

"FIRE-BREAK" FUNCTION

This function can be used when the RB 3300 back-amplifier board (A.C.U.) is equipped with the optional SB 3320 FAULT DETECTOR board,
and makes it possible to drive the amplifier controlled by the RB 3300 board with an emergency signal coming from a source not connected
to the RX 3000 system, interrupting the normal transmission of the signal coming from the audio matrix. This guarantees, even in the
event of a fault on a component of the RX 3000 system (e.g. OB 3230 AUDIO OUTPUT board), that a message with absolute priority can be
transmitted (e.g. fire alarm). To ensure the maximum certainty of intervention, the "fire-break" function acts exclusively at the hardwa-
re level.

"LINE FAULT" FUNCTION

The "LINE FAULT" function can be used when the RB 3300 back-amplifier board (A.C.U.) is equipped with the optional SB 3320 FAULT DE-
TECTOR board, and makes it possible to control the impedance of the speaker line driven by means of the RB 3300 board. Any malfunction
that causes a significant variation in the line impedance activates the respective alarm, which is transmitted to the CP 3100 control unit. The
malfunctions that can be detected are:
• short circuit between the two conductors of the speaker line,
• interruption of the speaker line,
• short circuit between the speaker line and the earth circuit.
IMPORTANT NOTE
• When the RB 3300 board is controlling a backup amplifier, the "LINE FAULT" function can only be used to detect a short circuit between
the speaker line and the earth circuit; the function does not detect a short circuit between the two conductors of the speaker line or
an interruption of the speaker line.

"PA FAULT" FUNCTION

The "PA FAULT" function can be used when the RB 3300 back-amplifier board (A.C.U.) is equipped with the optional SB 3320 FAULT DE-
TECTOR board. It enables a check for correct operation of the amplifier controlled by the RB 3300 board by picking up the signal on the
speaker output. Any amplifier malfunction that causes a significant decrease in the power transmitted activates the respective alarm, which is
transmitted to the CP 3100 control unit. By programming the CP 3100 unit in a particular way, when the amplifier goes into alarm status, a
backup amplifier is automatically activated in its place.

"ALC" FUNCTION

The "ALC" function (Automatic Level Control) can be used when the RB 3300 back-amplifier board (A.C.U.) is equipped with the optional LB
3340 DIGITAL ALC board. This function permits automatic control of the signal/noise ratio in the area covered by the sound system; that is, it
makes it possible to maintain a constant margin of level between the signal diffused and the ambient noise in order to ensure perfect clarity
of the sound messages. This characteristic is particularly useful in premises that are subject to strong noise variations. The "ALC" function is
based on the use of condenser microphones (up to four), or loudspeakers with line transformer operating as microphones, used for detecting
the ambient noise level. The signal picked up is processed digitally to control an electronic attenuator in order to guarantee perfect regulation
of the signal.
IMPORTANT NOTE
• The "ALC function" cannot be used when the RB 3300 board is controlling a backup amplifier; therefore, a "BACKUP" A.C.U cannot
be equipped with the LB 3340 DIGITAL ALC board.
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