Monacor POWER concept HPB-240/SW Manual De Instrucciones página 8

GB drop is increasing and the output power of the booster
is reducing.
The cross sections for other cable lengths can be cal-
culated according to the following formula:
I (l
max
x
q =
15
q
recommended cross section
=
I
current load
max = max.
l cable length in m of the +12 V cable
=
a
l
cable length in m of the ground cable
=
b
5.1.4 Terminal GND (6)
Connect the ground terminal GND via a cable of cor-
responding cross section (same cross section as the
+12 V power supply cable) with the ground of the car
or directly with the negative terminal of the car battery.
To avoid ground loops, the ground of the car radio
must be placed at the point where also the booster is
grounded.
5.2 Inputs
Connect both booster inputs (4) via cinch cables with
the corresponding line outputs at the car radio.
If there are no line outputs at the car radio, the
speaker outputs of the car radio can be connected via
a corresponding transformer (e. g. MONACOR FGA-
20) with the booster inputs.
5.3 Speakers
The greatest output power is obtained with the
connection of 4 Ω speakers. Also 8 Ω speakers may be
connected but in this case the output power is reduc-
ed. All speakers must be connected with 2 poles, i. e.
without common ground connection!
The exact connection depends on the number of
the speakers used!
5.3.1 Two speakers (fig. 3)
The capability of each speaker must at least be
60 W rms (HPB-260/..) resp. 40 W rms (HPB-240/..).
Connections of the speakers at the terminals (10):
L+ = + left speaker
L- = - left speaker
R- = - right speaker
R+ = + right speaker
The sliding switch SUBWOOFER (2) must be in posi-
tion OFF.
5.3.2 One speaker (fig. 4)
With the connection of one subwoofer the output
power can be doubled. For the subwoofer a crossover
system has been integrated which is activated with the
switch SUBWOOFER (2). The capability of the sub-
woofer must at least be 120 W rms (HPB-260/..) resp.
80 W rms (HPB-240/..).
Connections of the subwoofer at the terminals (10):
L+ = remains unconnected
L- = - subwoofer
R- = remains unconnected
R+ = + subwoofer
8
l )
a + b
in mm
in A
The sliding switch SUBWOOFER (2) must be in posi-
tion 120 Hz or 80 Hz, according to the recommenda-
tions of the subwoofer manufacturer. Adjust the fre-
quency at which the subwoofer stops working.
6 Level and Sound Matching
Prior to switching on the level and sound matching,
2
the complete wiring of the booster should be
checked once again. Only then connect the positive
terminal of the car battery again.
For an optimum level matching of the booster to the
car radio the control LEVEL CONTROL (3) is provided.
If required, with the BASS/TREBLE controls (1) the
low frequencies can be boosted by 18 dB and the high
frequencies by 12 dB.
7 Trouble Shooting
If no sound can be heard after switching on the car
audio system, it is easier to locate the fault while
watching the LED (9) of the booster at first:
7.1 LED does not light
1) Check the fuse (5) at the booster and the additional
fuse at the car battery. Replace defective fuses.
2) Control the +12 V power supply cable as well as the
ground cable for correct connection and for inter-
ruption.
3) Check if there is +12 V at the terminal RMT (8) of
the booster. If not, remove the cable at the terminal
RMT and shortly bridge the terminals RMT (8) and
+12 V (7). If the booster now switches on, the error
is due to the missing control voltage. Check the
+12 V output of the car radio (resp. the separate
switch or the ignition key lock) and the correspond-
ing connection cable to the booster.
7.2 LED shows a green light, but there is no sound
1) Check speakers, speaker cables, and their correct
connection. Especially with bridge operation the
correct speaker connection is very important.
2) Check the connections at the booster inputs.
3) Check the car radio outputs.
7.3 LED shows a red light
The LED shows a short-circuit at the booster outputs,
an overload, or an overheating of the booster. The pro-
tection circuit is activated. For deactivating the protec-
tion circuit the error must be removed and the booster
must be switched off for at least 10 seconds.
1) Check speakers and speaker cables for short-cir-
cuit.
2) In case of an overload check the speaker imped-
ances. The impedance must not be below 4 Ω with
bridge operation and not below 2 Ω with 2-channel
operation.
3) In case of an overheating let the booster cool down
and improve the ventilation.