RCF MT 7308 User manual

USER MANUAL
MANUALE D’USO
MT 7308 -DXT 7000EN SYSTEM
MT 7308 Universal Monitoring Unit
-SISTEMA DXT 7000EN
MT 7308 Unità di monitoraggio
universale.

TABLE OF CONTENTS
INDICE
ENGLISH
SAFETY AND OPERATING PRECAUTIONS
DESCRIPTION
REAR PANEL
FRONT PANEL LEDS
CONNECTION
SETTINGS
STARTUP
OPERATION
TROUBLESHOOTING
ITALIANO
AVVERTENZE PER LA SICUREZZA
DESCRIZIONE
PANNELLO POSTERIORE
LED SUL PANNELLO FRONTALE
COLLEGAMENTO
IMPOSTAZIONI
AVVIO DEL SISTEMA
FUNZIONAMENTO
RISOLUZIONE DEI PROBLEMI
4
6
9
11
11
12
14
16
17
18
20
23
25
25
26
28
30
31

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IMPORTANT NOTES
Before connecting and using this product, please read this instruction manual carefully
and keep it on hand for future reference.This manual is to be considered an integral part
of this product and must accompany it when changing ownership, as a reference for
correct installation and use as well as for the safety precautions.
RCF S.p.A. will not assume any responsibility for the incorrect installation and / or use of
this product.
WARNING: To prevent the risk of re or electric shock, never expose these products to
rain or humidity.
SAFETY AND OPERATING PRECAUTIONS
1. All the precautions, in particular the safety ones, must be read with special attention,
as they provide important information.
2. Make sure that no objects or liquids can get into this product, as this may cause a
short circuit.
This apparatus shall not be exposed to dripping or splashing.
No objects lled with liquid (such as vases) and no naked sources (such as lighted
candles) shall be placed on this apparatus.
3. Loudspeaker lines can have a sufciently high voltage (i.e. 100 V) to involve a risk of
electrocution: complete the installation and all connections before turning the system on.
The terminals marked with the symbol are HAZARDOUS LIVE and their
connection is to be made by an INSTRUCTED PERSON or the use of ready-made
cables is required.
4. Assure all connections have been made correctly.
5. Protect all cables from damage; make sure they are positioned in a way that they
cannot be stepped on or crushed by objects.
6. Never attempt to carry out any modications or repairs. Contact your authorized
service centre or qualied personnel when any product does not work properly.
7. Should any product emit a strange odour or even smoke, turn the system off
immediately.
8. Do not connect any equipment or accessories not foreseen.
9. RCF S.p.A. strongly recommends this product is only installed by professional qualied
installers (or specialised rms) who can ensure a correct installation and certify it
according to the regulations in force. The entire audio system shall comply with the
current standards and regulations regarding electrical systems.
10.Mechanical and electrical factors need to be considered when installing a
professional audio system (in addition to those which are strictly acoustic, such as
sound pressure, angles of coverage, frequency response, etc.).
IMPORTANT NOTES
SAFETY AND OPERATING PRECAUTIONS

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11.Hearing loss
Exposure to high sound levels can cause permanent hearing loss. The acoustic
pressure level that leads to hearing loss is different from person to person and
depends on the duration of exposure. To prevent potentially dangerous exposure
to high levels of acoustic pressure, anyone who is exposed to these levels should
use adequate protection devices. When a transducer capable of producing high
sound levels is being used, it is therefore necessary to wear ear plugs or protective
earphones.
12.To prevent inductive effects from causing hum, noise and a bad system working,
loudspeaker lines should not be laid together with other electric cables (mains),
microphone or signal cables connected to amplier inputs.
13.All loudspeaker lines shall have wires with a suitable section (twisted, if possible, to
reduce inductive effects due to surrounding electro-magnetic elds) and a sufcient
electrical insulation.
Refer to local regulations since there may be additional requirements about cable
characteristics.
14.Do not use solvents, alcohol, benzene or other volatile substances for cleaning the
external parts of this product. Use a dry cloth.

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MU 7100EN (the main unit of the RCF DXT 7000EN system) has eight 80 W ampliers
inside.
In case of higher power is needed, it is possible to create ‘locked groups’ to get 160 W,
240 W or even 320 W outputs. Yet, ‘locked groups’ reduce the available channels.
The MT 7308 universal monitoring unit makes it possible to integrate external (constant
voltage) ampliers into the monitored DXT 7000EN voice evacuation system.
This is a big advantage, especially when a system has a lot of lines, each having a
considerable loudspeaker load.
It is possible to use any professional single / multichannel amplier equipped with a 0 ÷
6 dBu balanced audio input and 50/70/100 V constant voltage output(s).
One or two MT 7308 can be linked to each MU 7100EN main unit.
One unit can be used for up to eight external ampliers (and its loudspeaker line
monitoring).
Max. power for each external amplier: 500 W.
The eighth amplier can be set (through the dip-switch no.8) as spare that automatically
replaces a faulty one.
Its size is half 19” rack unit (9.5”), two
MT 7308 can be installed into 19” 1U
rack.
The MT 7308 can be set by using
the PC conguration software and
communicates with the host MU
7100EN via ‘local bus’, from which
receives the power supply voltage as
well.
External amplier audio inputs can be
linked to the MU 7100EN loudspeaker
outputs through dedicated attenuators
that reduce signal levels to 0 dBu.
An ‘end of line’ unit needs to be linked
to the end of each loudspeaker line to
get a proper line monitoring.
RCF S.p.A. thanks you for purchasing this product, which has been designed
to guarantee reliability and high performances.
DESCRIPTION
Figure 1: system block diagram, all channels used for ext. ampliers
END OF
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LINE UNIT
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LINE UNIT
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LINE UNIT
END OF
LINE UNIT
100 V / 70 V
LOUDSPEAKER LINES
MT 7308MU 7100EN
LOCAL BUS
EXTERNAL
AMPLIFIERS
ATTENUATORS
0 dB
0 dB
0 dB
0 dB
0 dB
0 dB
0 dB
0 dB

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ENGLISH
Figure 2: hybrid solution, only 4 channels used for ext. ampliers
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END OF
LINE UNIT
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END OF
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END OF
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100 V / 70 V
LOUDSPEAKER LINES
MT 7308
LT 7208EN
MU 7100EN
LOCAL BUS
EX. AMPL.
ATTENUATORS
0 dB
0 dB
0 dB
0 dB
Figure 3: hybrid solution with spare amplier
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LINE UNIT
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LINE UNIT
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END OF
LINE UNIT
END OF
LINE UNIT
100 V / 70 V
LOUDSPEAKER LINES
MT 7308
LINE 1
LINE 5
LINE 2
LINE 6
LINE 3
LINE 7
LINE 4
LINE 8
/SPARE
MU 7100EN
LOCAL BUS
EX. AMPL.
ATTENUATORS
0 dB
0 dB
0 dB
0 dB
LT 7208EN
SPARE

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Figure 4: hybrid solution with spare amplier and dual lines (A/B)
END OF
LINE UNIT
END OF
LINE UNIT
END OF
LINE UNIT
END OF
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LINE UNIT
100 V / 70 V
LOUDSPEAKER LINES
MT 7308
LINE 1
LINE 1
LINE 5
LINE 5
LINE 2
LINE 2
LINE 6
LINE 6
LINE 3
LINE 3
LINE 7
LINE 7
LINE 4
LINE 4
LINE 8
/SPARE
LINE 8
/SPARE
MU 7100EN
LOCAL BUS
EX. AMPL.
ATTENUATORS
0 dB
0 dB
0 dB
0 dB
LT 7208EN
SPARE
A
B

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ENGLISH
MAIN FEATURES
-Universal amplier and loudspeaker line monitoring unit.
-It allows cost-effective hybrid systems, by using both MU 7100EN internal ampliers and
external single / multichannel ampliers.
-One or two MT 7308 can be linked to each MU 7100EN main unit.
-A single MT 7308 can monitor up to 8 external ampliers and loudspeaker lines.
-Adjustable accuracy: 5% change in impedance can be measured.
-Fault information sent via ‘Local Bus’ to MU 7100EN.
-It is powered by the ‘Local Bus’ (no external power supply is needed).
-External amplier max. power: 500 W (per each channel).
-Automatic changeover of a faulty amplier by the spare one (if foreseen).
REAR PANEL
1LINE 1 to LINE 8: 50 / 70 / 100 V loudspeaker line inputs / outputs.
Screw terminal pins for each of the 8 lines:
IN + Loudspeaker line input +
IN – Loudspeaker line input –
GGround
OUT + Loudspeaker line output +
OUT – Loudspeaker line output –
2ADDRESS DIP-switches
DIP 1 to 4: MT 7308 digital address setting.
Each unit has its own individual digital address that is set through the rst 4 DIP-
switches. Each digital address must be set before powering the system.
One or two MT 7308 can be linked to each MU 7100EN main unit.
Two or more devices (linked to the same bus) cannot have the same digital address.
OFF
ON
1 2 3 4 5 6 7 8
1
2 3 4

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ENGLISH
Digital address setting through DIP-switches:
DIP 5: not used.
DIP 6: faulty line switch off-relays (OFF: disabled, ON: enabled).
DIP 7: not used.
DIP 8: automatic spare amplier insertion (OFF: disabled, ON: enabled).
ADDRESS DIP-SWITCHES ADDRESS DIP-SWITCHES
1 2 3 4 1 2 3 4
1ON OFF OFF OFF 9 ON OFF OFF ON
2 OFF ON OFF OFF 10 OFF ON OFF ON
3ON ON OFF OFF 11 ON ON OFF ON
4 OFF OFF ON OFF 12 OFF OFF ON ON
5ON OFF ON OFF 13 ON OFF ON ON
6 OFF ON ON OFF 14 OFF ON ON ON
7ON ON ON OFF 15 ON ON ON ON
8 OFF OFF OFF ON - - - - -
3DATA: ‘Local Bus’ input. Link this port to the MU 7100EN local bus.
4LINK: ‘Local Bus’ parallel output.

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FRONT PANEL LEDS
The front panel LEDs indicate the current unit status:
After xing faults, all fault indications will be reset.
Anyhow, the fault is listed to the system Error Log.
Note: the Mt 7308 coNNectioN should be carried out carefully, siNce possible iNcorrect
settiNgs caN daMage exterNal aMplifiers (aNd also loudspeakers).
Connect the MU 7100EN ‘Local Bus’ to the MT 7308 DATA 3input through a CAT-
5 cable with RJ45 plugs.
The LINK 4parallel output can be used to link other devices to the ‘Local Bus’.
External amplier audio inputs can be linked to the MU 7100EN loudspeaker outputs
through dedicated attenuators that reduce signal levels to 0 dBu (see the gure).
If necessary, each level can be adjusted by the respective trimmer.
The factory attenuation is set for a 6 dBu amplier input sensitivity.
CONNECTION
‘ON’
green LED
‘FAULT’
red LED
dark dark Device off
dark steady lit No status (requesting)
blinking steady lit No acceptable reference for monitored lines
steady lit dark Device is monitoring, no faults
steady lit steady lit Device is monitoring, line or amplier faults
steady lit blinking Upper limit exceeded for monitored lines
ON FAULT (red)(green)

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SETTINGS
MT 7308 can be set by using the PC software.
Open the system parameter window: select
“Dene Systems/System Parameters”.
Make sure the ‘System Monitoring’ is enabled.
Open the MU 7100EN setup window: select
“Dene Systems/Devices/MU 7100 System Units”.
Amplier monitoring needs to be disabled
for those output channels connected to
the MT 7308 unit.
Select “Dene Systems/Devices/MT 7308 Universal Monitoring Unit” to open its
respective window.

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PARAMETERS
Name: each MT 7308 can be named.
Local Bus Host: system unit (MU 7100EN), to which the MT 7308 is linked.
MU 7100 pilot settings: the pilot tone is generated by the MU 7100EN unit and can
be activated by selecting ‘Active’ on each output channel.
Pilot tone levels are important settings to get accurate monitoring results.
Default pilot tone level is –24 dB.
For a trial, each pilot tone can be adjusted by moving it cursor and then clicking the
‘Update Pilot Settings’ button. Yet, new pilot tone levels are not stored to memory.
To get a new default conguration, its le with proper settings must be loaded to the
system.
Important: a too high pilot tone level can damage external power ampliers or/and
loudspeakers.
A proper pilot tone level range is from – 30 dB to –10 dB.
Address: MT 7308 digital address setting, each unit shall have its own address.
Monitoring Interval: monitor interval time (seconds).
Monitoring Active: it enables the selected MT 7308 monitoring (note: the system
overall monitoring is to be activated as well).
Tolerance: monitoring tolerance. The value 0 means no monitoring, any other value
activates the respective channel monitoring. Recommended monitoring tolerance is 10 ÷
30%.
If needed, the spare amplier (line 8 input) can be monitored too.
Recommended tolerance for the spare amplier is 80‐100%.
DSP OUTPUT SETTINGS
It is recommended to set a low-pass lter with cutoff frequency of 15 kHz for every
channel monitored by MT 7308 units.
A second or even a third low-pass lter (f: 15 kHz) can be inserted if necessary.
UPLOAD THE CONFIGURATION
Finally, upload the conguration from the PC to the system.

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STARTUP
The system should be reset after loading a new conguration.
This can be done by clicking the ‘Software reset All’ button in the MU 7100 setup
window (select ‘Dene Systems/Devices/MU 7100 System Units’).
After rebooting the system, the system monitoring will start in one minute.
The MT 7308 front LEDs indicate its current status.
After the startup, the red FAULT LED is steady lit until the MT 7308 gets its status
information from its host unit (MU 7100EN) and the green ON LED starts blinking (this
indicates that MT 7308 has started to measure pilot tone levels as references).
The entire level range is 0 ÷ 240 (values can be read in the MT 7308 monitoring
window).
An acceptable reference level is in the range 10 ÷ 200 (note: all MT 7308 units need
acceptable references for all monitored lines to start measuring properly).
Try to adjust pilot tone levels into the 100 ÷ 150 range, in order to get the maximum
measuring resolution. This level range means around 4 V RMS pilot tone (measured from
the line).
When measuring, make sure your voltmeter is capable to measure high frequencies (20 kHz).
When the MT 7308 has got acceptable reference levels for all activated channels, its
FAULT LED turns off and its ON LED is steady lit: now, the system is monitoring.
Note: wheN chaNgiNg gaiN levels or settiNg the pilot toNe duriNg the operatioN, refereNces should be
set to achieve New levels. this caN be doNe by clickiNg a‘Set Reference Values’ buttoN iN the
Mt 7308 setup wiNdow.
ON FAULT (red)(green)

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The status of each monitored channel can be supervised in the result table, which shows
pilot tone reference levels and measurements.
AMPLIFIER: indicates the amplier status of the respective channel:
either ‘OK’ or ‘Fail’.
SPEAKERS: indicates the loudspeaker line status of the respective channel:
either ‘OK’ or ‘Fail’.
Example: the channel 2 loudspeaker line is faulty

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NORMAL OPERATION
When a MT 7308 unit has got acceptable reference values for all monitored lines, it starts
measuring all monitored lines constantly.
Measuring is stopped when the system is switched to stand-by.
LINE/SPEAKER FAULT
When the measuring result of monitored line differs from the reference more than the
given tolerance (and is over 10 measurement units), the MT 7308 will indicate ‘line fault’.
If the faulty line switch off-relays are enabled (dip-switch no.6), the faulty line will be
disconnected from the amplier.
If the measuring result returns to a normal value, the error will be automatically reset and
the line re-connected to the amplier.
Line fault is indicated by the front panel red LED (and DXT 7000EN system error
indication).
AMPLIFIER FAULT
When the measuring result is less than 10 measurement units, the MT 7308 will indicate
‘amplier fault’.
If both faulty line switch off-relays (dip-switch no.6) and spare amplier (dip-switch no.8)
are enabled, the respective loudspeaker line will be linked to the spare amplier.
Any previously cut line (due to a line fault) will be re-connected.
If the measuring result returns to a normal value, the error will be automatically reset and
the line re-connected to its own amplier.
Amplier fault is indicated by the front panel red LED (and DXT 7000EN system error
indication).
OPERATION

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TROUBLESHOOTING
- After the startup, the FAULT LED is steady lit, nothing else happens.
Wait at least 1 minute, then check:
-Conguration, monitoring on, etc.
-Digital addresses.
-The local bus cable.
- After the startup, the FAULT LED is steady lit and the ON LED is blinking,
nothing else happens.
-Has software reset been done after loading the conguration?
-Pilot tone levels in each input should be around 4 V RMS (or in the 170-200 range
read in the PC software).
-If you nd difcult to get the pilot tone to the right level, sensitivity can be
adjusted (normally, not needed) by the R33 trimmer, which is located on the MT
7308 printed circuit board.
- Every now and then a loudspeaker line fault is reported, but everything
seems to be working well.
Check the level during paging or playing, as it could be too high and cause amplier
clipping. Distortion includes a lot of high frequency harmonics and this could cause
interferences to the measuring results. To avoid this problem, insert low-pass lters
as described in ‘DSP OUTPUT SETTINGS’.

18
ITALIANO
IMPORTANTE
Prima di collegare ed utilizzare questo prodotto, leggere attentamente le istruzioni
contenute in questo manuale, il quale è da conservare per riferimenti futuri.
Il presente manuale costituisce parte integrante del prodotto e deve accompagnare
quest’ultimo anche nei passaggi di proprietà, per permettere al nuovo proprietario di
conoscere le modalità d’installazione e d’utilizzo e le avvertenze per la sicurezza.
L’installazione e l’utilizzo errati del prodotto esimono la RCF S.p.A. da ogni responsabilità.
ATTENZIONE: Per prevenire i rischi di amme o scosse elettriche, non esporre mai
questo prodotto alla pioggia o all’umidità.
AVVERTENZE PER LA SICUREZZA
1. Tutte le avvertenze, in particolare quelle relative alla sicurezza, devono essere lette
con particolare attenzione, in quanto contengono importanti informazioni.
2. Impedire che oggetti o liquidi entrino all’interno del prodotto, perché potrebbero
causare un cortocircuito. L’apparecchio non deve essere esposto a stillicidio o a
spruzzi d’acqua; nessun oggetto pieno di liquido (quali vasi) e nessuna sorgente di
amma nuda (es. candele accese) deve essere posto sull’apparecchio.
3. Le linee diffusori (uscite dell’amplicatore) possono avere una tensione
sufcientemente alta (es. 100V) da costituire un rischio di folgorazione per le persone:
completare l’installazione e tutte le connessioni prima di accendere il sistema.
I terminali marcati con il simbolo sono da ritenersi ATTIVI e PERICOLOSI ed
il loro collegamento deve essere effettuato da PERSONE ADDESTRATE oppure si
devono utilizzare cavi già pronti.
4. Assicurarsi che tutte le connessioni siano corrette.
5. Accertarsi che tutti i conduttori elettrici non possano essere calpestati o schiacciati da
oggetti, al ne di salvaguardarne la perfetta integrità.
6. Non effettuare sul prodotto interventi / modiche / riparazioni. Contattare un centro
d’assistenza autorizzato nel caso che il prodotto non funzioni correttamente.
7. Nel caso che dal prodotto provengano odori anomali o fumo, spegnere
immediatamente il sistema.
8. Non collegare apparecchi ed accessori non previsti.
9. La RCF S.p.A. raccomanda vivamente che l’installazione di questi prodotti sia eseguita
solamente da installatori professionali qualicati (oppure da ditte specializzate) in
grado di farla correttamente e certicarla in accordo con le normative vigenti.Tutto il
sistema audio dovrà essere in conformità con le norme e le leggi vigenti in materia di
impianti elettrici.
10.I fattori meccanici ed elettrici sono da considerare quando si installa un sistema audio
professionale (oltre a quelli prettamente acustici, come la pressione sonora, gli angoli
di copertura, la risposta in frequenza, ecc.).
IMPORTANTE
AVVERTENZE PER LA SICUREZZA

19
ITALIANO
11.Perdita dell’udito
L’esposizione ad elevati livelli sonori può provocare la perdita permanente dell’udito.
Il livello di pressione acustica pericolosa per l’udito varia sensibilmente da persona
a persona e dipende dalla durata dell’esposizione. Per evitare un’esposizione
potenzialmente pericolosa ad elevati livelli di pressione acustica, è necessario che
chiunque sia sottoposto a tali livelli utilizzi delle adeguate protezioni; quando si
fa funzionare un trasduttore in grado di produrre elevati livelli sonori è necessario
indossare dei tappi per orecchie o delle cufe protettive.
Consultare i dati tecnici contenuti nei manuali istruzioni per conoscere le massime
pressioni sonore che i diffusori acustici sono in grado di produrre.
12.Per evitare che fenomeni induttivi diano luogo a ronzii, disturbi e compromettano il
buon funzionamento dell’impianto, le linee diffusori non devono essere canalizzate
insieme ai conduttori dell’energia elettrica, ai cavi microfonici, alle linee di segnale a
basso livello che fanno capo ad amplicatori.
13.I cavi per i collegamenti dei diffusori dovranno avere conduttori di sezione
adeguata (possibilmente intrecciati, per minimizzare gli effetti induttivi dovuti
all’accoppiamento con campi elettro-magnetici circostanti) ed un isolamento idoneo.
14.Non usare solventi, alcool, benzina o altre sostanze volatili per la pulitura delle parti
esterne dell’unità; usare un panno asciutto.

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L’unità centrale MU 7100EN (del sistema RCF DXT 7000EN) ha al suo interno otto
amplicatori da 80 W ciascuno.
Nel caso che sia richiesta una potenza superiore, è possibile creare dei “gruppi bloccati”
per ottenere uscite aventi potenza 160 W, 240 W o persino 320 W; tuttavia, questi gruppi
riducono il numero di canali disponibili.
L’unità MT 7308 permette di integrare il sistema DXT 7000EN con amplicatori esterni (a
tensione costante); opzione molto utile quando si hanno molte linee per diffusori (con un
carico considerevole di altoparlanti).
Si possono usare amplicatori a singolo canale o multicanale aventi ingressi audio
bilanciati con sensibilità 0 ÷ 6 dBu ed uscita / uscite a tensione costante 50 / 70 / 100 V.
Si possono collegare uno o due MT 7308 a ciascuna unità centrale MU 7100EN.
Un MT 7308 può essere usato no ad un massimo di otto amplicatori esterni (ed il
monitoraggio delle rispettive linee diffusori).
La potenza massima per ciascun amplicatore esterno è 500 W.
L’ottavo amplicatore può essere impostato (tramite il dip-switch nr.8) come riserva che si
inserisce automaticamente al posto di uno guasto.
Le sue dimensioni sono mezza unità
rack da 19”; due MT 7308 possono
essere installati in un unità rack da 19”.
L’unità MT 7308 può essere impostata
tramite il software di congurazione
per PC e comunica con l’unità centrale
MU 7100EN via “Local Bus”, dal quale
riceve anche l’alimentazione.
Gli ingressi audio degli amplicatori
esterni si collegano alle uscite
altoparlanti dell’unità centrale MU
7100EN solo tramite attenuatori
dedicati, i quali riducono il livello del
segnale a 0 dBu.
Un’unità di “ne linea” deve essere
collegata alla ne di ogni linea diffusori
in modo che questa sia correttamente
monitorata.
RCF S.p.A. Vi ringrazia per l'acquisto di questo prodotto, realizzato in modo
da garantirne l'afdabilità e prestazioni elevate.
DESCRIZIONE
Figura 1: schema a blocchi del sistema; tutti i canali sono usati con amplicatori esterni.
UNITÀ DI
FINE LINEA
UNITÀ DI
FINE LINEA
UNITÀ DI
FINE LINEA
UNITÀ DI
FINE LINEA
UNITÀ DI
FINE LINEA
UNITÀ DI
FINE LINEA
UNITÀ DI
FINE LINEA
UNITÀ DI
FINE LINEA
LINEE ALTOPARLANTI
100 V / 70 V
MT 7308MU 7100EN
LOCAL BUS
AMPLIFICATORI
ESTERNI
ATTENUATORI
0 dB
0 dB
0 dB
0 dB
0 dB
0 dB
0 dB
0 dB