Data sheet, Dvs-21, 4lsl – Procom 4LSL User Manual

Page 2: Brief description

Data Sheet

4LSL

Loudspeaker Function Card

In order to make a public address announcement it is necessary that the loud-
speaker circuits to be used are in functioning order. One way to gauge this is to
use the impedance which was measured during commissioning.
The 4LSL can be used to cyclically check loudspeaker circuits for deviations in
impedance.
To do this a measurement signal is required which is generated by the TG01
module. The functionality of the signal generator is also tested before each
measurement cycle by the 4LSL.

The 4LSL is part of an application for monitoring impedance in loudspeaker cir-
cuits and distributed loudspeaker circuits. It switches the sine wave generated by the
test signal generator to the loudspeaker circuit and compares the flow of current and
the voltage with previously made reference values.

WPS-04
WPS-08

Application example of loudspeaker circuit monitoring

* TW = Twin Wire

CPU1

DTA-012 -030/ -048/ -066/ -084/ -114

2TW *

TG01

DSS1

SV01

4NSA

V100

Havarie

V100

4LSL

LC2 ..

LC 1

LC 2

LC n

Monitoring of loudspeakers according to the
equipment level 1 of the Deutschen Bahn AG

Brief Description:

DVS-21

LC 1

LC1

LC 2

LC n

Date:

13.03.2009 Page:

2/7 Author:

Document-No.:

DB_4LSL_2830_01