Connection Examples For Groups Of A.c.u - rcf RB 3300 Manual De Uso

CONNECTING THE "AUDIO BUS" LINE
NOTES
• In the descriptions in this section, the "preceding" A.C.U. (back-amplifier board) means the one which, in the group of A.C.U.s, is connec-
ted upstream from the current one with respect to the last backup amplifier.
• In the descriptions in this section, the "following" A.C.U. (back-amplifier board) means the one which, in the group of A.C.U.s, is connected
downstream from the current one with respect to the last backup amplifier.
The "audio bus" line (see the section "BOARD OPERATION") is connected using the "M6" and "M7" terminal strips.
The "M6" terminal strip is used for the input of the "audio bus" line (see the section "BOARD OPERATION"). If the "M6" terminal strip be-
longs to a "NORMAL" unit, it must be connected with the "M7" terminal strip of the following "NORMAL" unit (where present and belonging
to the same group). If the "M6" terminal strip belongs to the last "NORMAL" unit of the "audio bus" line (the furthest from the backup am-
plifier), it is advisable to short circuit terminals "1" and "2" of the terminal strip using the 1 kohm resistor provided with the CP 3100 control
unit, in order to prevent the backup amplifier from picking up noise when no audio signal is passing on the "audio bus" line. If the "M6" ter-
minal strip belongs to a "BACKUP" unit, it must not be connected.
The "M7" terminal strip is used for the output of the "audio bus" line (see the section "BOARD OPERATION"). If the "M7" terminal strip be-
longs to an A.C.U. which is preceded by a "NORMAL" unit, it must be connected with the "M6" terminal strip of the preceding unit. If the
"M6" terminal strip belongs to the first "NORMAL" unit in the group (the nearest to the backup amplifier), it must be connected:
• with the "M1" terminal strip of the first "BACKUP" unit ("BACKUP" unit number 1).
• with the input of the backup amplifier, when only one backup amplifier is present in the group and it is not controlled by an RB 3300 back-
amplifier board.
If the "M7" terminal strip belongs to a "BACKUP" unit, it must be connected:
• with the "M1" terminal strip of the next "BACKUP" unit ("BACKUP" unit number 2, 3, etc.), when an additional backup amplifier is present
and is controlled by an RB 3300 back-amplifier board.
• with the input of the additional backup amplifier of the group (backup amplifier number 2, 3, etc.), when it is present and is not controlled
by an RB 3300 back-amplifier board.
If the "M7" terminal strip belongs to the only or the last "BACKUP" unit of the group, it must not be connected.
Using a screened cable, connect the "M6" terminal strip (ref. 26 – Fig. 1, page 72) and "M7" terminal strip (ref. 25 – Fig. 1, page 72) as shown
in Figure 10 on page 75.
CONNECTING THE AUXILIARY ALARM CONTACT OF THE AMPLIFIER
If the amplifier being controlled by the RB 3300 board is equipped with an auxiliary alarm contact that switches to closed when a protection
device intervenes, or when the unit operates in an abnormal way (e.g. operation in overload), connect the "M5" terminal strip (ref. 22 – Fig. 1,
page 72) to the contact as shown in Figure 11 on page 75.
NOTE
• Terminal n° 2 corresponds to the GND pole of the 5V and 24V power supply voltages of the board.
CONNECTION EXAMPLES FOR GROUPS OF A.C.U.s
Some possible connection configurations of groups of A.C.U.s are described below. To simplify the representation of the connections, the
"monitor bus" line connection is not indicated, as it is not necessary for understanding how the various configurations work. Further infor-
mation in this regard can be found in the section "CONNECTING THE 'MONITOR BUS' LINE".
EXAMPLE 1
The example in Figure 13 on page 76 shows a group of A.C.U.s composed of two or more ("n") primary amplifiers, each controlled by an RB
3300 board ("NORMAL" A.C.U.), and one backup amplifier for all the primary amplifiers of the group, which is not controlled by an RB 3300
board.
EXAMPLE 2
The example in Figure 14 on page 77 shows a group of A.C.U.s composed of two or more ("n") primary amplifiers, each controlled by an RB
3300 board ("NORMAL" A.C.U.), and one backup amplifier for all the primary amplifiers of the group, which is also controlled by an RB 3300
board (1 "BACKUP" A.C.U.).
EXAMPLE 3
The example in Figure 15 on page 77 shows a group of A.C.U.s composed of two or more ("n") primary amplifiers, each controlled by an RB
3300 board ("NORMAL" A.C.U.), and two backup amplifiers for all the primary amplifiers of the group, the second of which is not controlled
by an RB 3300 board (only 1 "BACKUP" A.C.U.).
EXAMPLE 4
The example in Figure 16 on page 78 shows a group of A.C.U.s composed of two or more ("n") primary amplifiers, each controlled by an RB
3300 board ("NORMAL" A.C.U.), and two backup amplifiers for all the primary amplifiers of the group, both controlled by RB 3300 boards (2
"BACKUP" A.C.U.s).
TERMINAL STRIP TERMINAL FUNCTION
M6 N° 1: "hot" balanced audio signal (low level)
N° 2: "cold" balanced audio signal (low level)
M7 N° 1: audio signal GND
N° 2: "hot" balanced audio signal (low level)
N° 3: "cold" balanced audio signal (low level)
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