13
XLR-3-31/XLR-3-32 — INTERCOM LINE
PIN 1
GND
PIN 2
+VDC
PIN 3
SIGNAL
Certain rules have to be followed when installing the cables of an intercom system. This is to
avoid ground loops and to minimize the power loss and possible effect of electromagnetic fields.
Do not connect the XLR pin 1 to the XLR metal housing or to metal wall boxes to avoid ground
loops. The ground loop could increase notably the system background noise.
Do not close the intercom line connection (avoid closed loops). Each intercom line leaves from
the base station towards the remote stations, but it does not return to the master station. If the
connection is closed, a ground loop with the increase from the system noise will take place.
Use high quality cables and minimize its longitude. Avoid using low quality cables and
excessive cable runs as it affects in power loss, channel crosstalk and frequency response.
Place the base station in the closest possible position to the maximum consumption zone; that
is to say to the zone in which more external units are placed.
The next picture shows the habitual connection of an intercom system comprised by four
beltpack units (two per channel) and a WBS-202 base station.
WB-200 SERIES INTERCOM SYSTEM — WBS-202 DUAL CHANNEL WIRELESS BASE STATION
