Operation; Protective Circuit; Specifications - Monacor PA-912S Bedienungsanleitung

230 V~/50 Hz
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4.2.2 Signal source
As a signal source, connect a unit with line
level output (PA mixing amplifier, preamplifier,
mixer etc .) to the XLR / 6 .3 mm jack INPUT (10) .
4.2.3 Additional amplifier
If the number of speakers required is higher
than the number admissible for the amplifier,
an additional amplifier will be required . Con-
nect the input of the additional amplifier to
the XLR connector LINK (9) .
4.2.4 Power supply
Use the mains cable provided to connect the
mains jack (4) to a socket (230 V/ 50 Hz) .

5 Operation

1) Use the selector switch 100V/70V (6) to
set the operating mode according to the
speakers connected .
2) Before switching on the amplifier for the
first time, set the control LEVEL (1) to the
left stop to make sure that the initial vol-
ume will not be too high . Then switch on
the amplifier with the mains switch (3) .
The power LED PWR (2) will light up
and the LED 100V or 70V will indicate the
operating mode adjusted . While the am-
plifier is switched on, it will be muted and
the LED PROT will light up .
3) Feed a signal to the input INPUT . Use the
control LEVEL to adjust the volume . The
LED SIG will light up at a specific signal
level . In case of overload, the red LED CLIP
will light up . In this case, reduce the vol-
ume with the control .
4) If there is a hum noise, this noise may
be due to a ground loop . Ground loops
occur, for example, when two units are
connected both via their signal ground and
via the protective conductor of the power
supply or via a conductive connection of
their housings in the rack .
To separate a ground loop, set the se-
lector switch (8) to the position LIFT . If the
hum noise starts in the position LIFT, set
the switch to GND . In case of doubt, test
both positions to find the optimum setting .
All rights reserved by MONACOR
may be reproduced in any form or by any means for any commercial use.
OUTPUT
70V/
COM COM COM 100V 100V
70V
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6 Protective Circuit

The amplifier is equipped with a protective
circuit against overheating, overload and
short circuit at the speaker output . While
the amplifier is switched on, it will be muted
(switch-on delay) and the LED PROT (2) will
briefly light up . If, however, the LED lights
permanently or lights up during operation,
the amplifier is overheated or overloaded or
there is a short circuit at the speaker termi-
nals OUTPUT (5) . Switch off the amplifier and
eliminate the fault .
In case of overheating, do not switch off
the amplifier, but set the control LEVEL (1)
to the left stop . This will reduce the load on
the power amplifier and the fan/fans will still
cool it .
1 . In case of overload, reduce the number of
speakers connected or, if possible, reduce
the power consumption of the speakers .
Use a second PA amplifier, if required (see
chapter 4 .2 .3) .
2 . In case of overheating, improve the air cir-
culation (also see chapter 4 .1) .
3 . In case of short circuit, locate and eliminate
the short circuit .

7 Specifications

Model
Power rating
Output impedance
Input sensitivity
Input impedance
Input jack
Frequency range
S / N ratio, A-weighted
THD
Power supply
Power consumption
Ambient temperature
Dimensions (W × H × D)
Weight
® INTERNATIONAL GmbH & Co. KG. No part of this instruction manual
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PA-912S
120 W
80 Ω at 100 V
40 Ω at 70 V
670 mV
XLR / 6 .3 mm jack, balanced
225 VA max .
483 × 44 × 255 mm, 1 rack space
3 .5 kg
LINK
1 2
1 2
LIFT
3
3
INPUT
GND
8 9 10
PA-924S PA-948S
240 W 480 W
40 Ω at 100 V 20 Ω at 100 V
20 Ω at 70 V 10 Ω at 70 V
650 mV 710 mV
10 kΩ
80 – 16 000 Hz
> 98 dB
< 1 %
230 V/ 50 Hz
495 VA max . 1100 VA max .
0 – 40 °C
3 .8 kg 4 kg
Subject to technical modification .
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