Dynacord PMX-4R24, Operation Manual

Page: 26 / 34

Operation
Line supervision
For loudspeaker line supervision three different options are available. They differ in
performance, cost, and suitability for various applications and situations.
In general the device can detect open circuit and short circuit. In case of an open circuit only a
fault message will be generated. In case of a short circuit a fault message will be generated
and the loudspeaker line will be automatically deactivated to avoid influence to other
loudspeaker lines.
Impedance measurement
The PMX-4CR12 controller is equipped with a speaker line impedance measurement function.
This function measures the effective values of the output current and the output voltage. The
impedance value of the connected speaker line is calculated using these measurements. Due
to the frequency and temperature dependence of the speaker line, the value obtained can vary
substantially. A continuous sinusoidal signal with an appropriate frequency is recommended
for the measurement. The voltage and current measurements do not claim to be a calibrated
measurement of absolute values. The measured value is compared with the reference
measurement in question and a good/bad status is indicated depending on the difference
between these two values. If the controller is replaced, the reference measurement must be
performed again. The impedance measurement is configured using the IRIS-Net software.
Parameter Value Default setting
(IRIS-Net)
Impedance range 20–10000 Ω (corresponds to 500 W to
1 W)
Impedance tolerance 6% ± 2 Ω
Frequency range 20–4000 Hz 30 Hz
Voltage range 0.1–1.0 V 0.5 V
Table 8.1: Impedance measurement specification
Notice!
The total impedance connected at the output on the amplifier (loudspeakers and cabling)
must be within the specified impedance range in terms of the test frequency (see the table
entitled “Impedance measuring specification”).
Notice!
To detect a line interruption to a single speaker, or the failure of a single speaker, the
following instructions must be observed: Do not connect more than five speakers to one
speaker line. All speakers on the speaker line must have the same impedance.
EOL slave module
End-of-line (EOL) technology enables the loudspeaker lines to be monitored for short-circuit
and interruptions. The EOL modules can be used for permanent supervision on not active and
active speaker lines, e.g. for speaker lines with permanent background music or if passive
volume controls are used.
8
8.1
8.1.1
8.1.2
26 en | Operation Promatrix 6000 Router
18-Jun-2015 | 03 | F01U306895 Operation manual