Operation; Protective Circuits - Omnitronic MPVZ SERIES Bedienungsanleitung

8. OPERATION

1
To prevent loud switching noise, first switch on all other units of the PA system.
2
Prior to switching on, turn the master control LEVEL and the level controls of the input channels to zero
to avoid a high volume at the beginning. Then switch on the unit with the power switch. The power
indicator lights up.
3
Turn up the master control LEVEL so that the mixing ration of the signal sources can be adjusted in an
optimum way.
4
Adjust the desired volume with the level controls ZONE 1 to 6 of the PA zones intended for PA
application. Turn the controls of the zones not used to zero.
5
Adjust the desired volume ratio with the level controls of the channels LINE 1 to 3 and MIC 1 to 3. Turn
the controls of the inputs not used to zero.
6
To improve the audibility of an announcement microphone channel PRIORITY MIC 1 is equipped with
an adjustable priority function. In case of an announcement via the channel PRIORITY MIC 1, the level
of the other channels is attenuated–depending on the rear control PRIORITY LEVEL. After the
announcement, the level of the other channels slowly returns to the original level.
7
Adjust the desired sound with the tone controls. By adjusting the tone controls, the high frequencies
(control TREBLE) and the low frequencies (control BASS) can be boosted or attenuated. With the
controls in mid-position, the frequency response is not affected.
8
Adjust the definite level of the total volume with the master control LEVEL. The 7-step LED row shows
the output level: the red LED 0 dB must not light permanently. Otherwise slightly turn back the master
control.
9
To release the chime prior to an announcement, press the button CHIME. Then also the level of the
channels is attenuated–depending on the rear control PRIORITY LEVEL.
Additional information on the operation
When operating the amplifying system, please make sure that the loudspeakers always sound well. When
distortions can be heard, either the amplifier or the loudspeaker is overloaded. Overloads can quickly lead to
amplifier or speaker damage. In order to avoid damage, please reduce the volume immediately when distortions
can be heard. Always check the sound pressure level with a meter in order to keep to the threshold.

8.1 Protective circuits

The protective circuits prevent damage to the speakers and the amplifier. If activated, the speakers are
electrically separated from the amplifier and the LED FAULT lights up:
• for a few seconds after switching-on until the speaker outputs are ready for operation
• in case of a short-circuit at a speaker output
• in case of over current
If the red LED FAULT lights up during operation or if it does not extinguish after switching on, the amplifier
has to be switched off and the cause of the fault has to be removed.
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