Eol Slave Module - Bosch PAVIRO PVA-4R24 User Manual

PAVIRO Router
Example:
The impedance value for 20 kHz for a cable with a capacitance value of 100 nF/km and a
length of 200 m is about 400 Ω. A 5 W loudspeaker has an impedance of about 2000 Ω. The
impedance of the cable including the loudspeakers is about 330 Ω. If the cable is broken near
the loudspeaker, the impedance difference is 70 Ω, which is about 21%.
–
The impedance of the loudspeaker depends on the frequency. The transformers in the
loudspeakers have a low impedance value at low frequencies. It is important to ensure that
the measurement limits (see Table 8.9) for the specific measurement frequencies are not
exceeded, especially for high-power loudspeakers.
Example:
The Sx300PIX loudspeaker has an impedance value of about 110 Ω at 1 kHz, but an impedance
value of 50 Ω at 30 Hz.
–
A ground fault of the loudspeaker cable can affect the impedance measurement of the
loudspeaker cable. If a ground fault and an impedance error are displayed simultaneously, the
cable ground fault must be corrected first.
Parameter
Impedance range
Impedance tolerance
Frequency range
Voltage range
Table 8.7: Impedance measurement specification
Notice!
i
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!
i
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.
8.1.2

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.
Method of operation
An EOL slave module PVA-1WEOL is installed at the end of the speaker line. The speaker line
is used for both the power supply of the module (via the non-audible pilot tone) and for bi-
directional communication between the EOL master in the output stage and the EOL slave
module (using very low-frequency signals). If a communication error occurs – for example, if
the EOL master does not receive a response from the slave – then an error message is
generated. The unique addressing of the slave modules means that multiple slave modules can
be connected to one speaker line.
Bosch Security Systems, B.V.
Loudspeaker impedance:
Ground fault:
Value
20-10000 Ω (corresponds to 500 W to 1 W)
6% ± 2 Ω
20-4000 Hz
0.1-1.0 V
User manual
Operation | en 25
2022-11 | 07 | F01U306901