IEB 400 Intercom Board
Page 2
Document
IM-IEB-400-1.1
3.1 Standard
Station
Audio Connections
Each IEB-400 intercom station is connected to the exchange with a single shielded twisted pair. The pair is
connected to terminals on the field interface terminal block. In turn these terminals are connected via a CBL-190 or
CBL-196 cable to the SCC-400 or SCC-401 in a DXL system. The shields are terminated at the field interface
terminal block and are grounded through the cable that connects the terminal block to the DXI or DXL exchange.
The audio line shielded twisted pair connects to pins 1 and 2 of a MTA-100-04 connector that plugs into CN8
header labeled Line. The shield is left open at the intercom station end of the cable. The pin assignments of CN8
header and the corresponding MTA-100-04 connections are shown in the following table: The connector pin outs
are assigned so that the orientation of the mating connectors is reversible.
Connector Pin
Signal
MTA Pins
1
Line +
Line +
2
Line -
Line -
3 Line
-
NC
4 Line
+
NC
Table 1 CN8 header pin signals
The maximum recommended distance to run 22-gauge twisted-pair shielded cable from a 400 series station to
SAB-400, SAB-401, SCC-400 or SCC-401 is 2500 feet (750 meters).
3.2
Connections to an MTA Connector
The connections to the intercom station are made with an AMP MTA-100 series connector. The intercom pair
should connect to pins 1 and 2 on a female 4-pin AMP MTA-100 series connector that plugs onto the header CN8
labeled Line on the intercom station printed circuit board. To make these connections you should use an AMP
Handle Assy 58074-1 tool with a 58246-1 head. The cable should be cut to length and the shield and outer jacket
should be trimmed back about 1/2 inch. Ensure that the shield is not exposed or it may short out exposed contacts
on the intercom PCB when it is installed.
To insert the signal wires into the connector you remove the white cover from the connector, insert the connector
into the tool from the left side (it will travel through the tool in the direction indicated by the arrow), pull the
trigger once to load the connector. Then insert the signal wire for pin 1 (do not strip the wire) into the hole on the
top of the tool and pull the trigger to insert the wire into the connector. Then repeat to install the other signal wire.
Finally, remove the connector from the tool, replace the cover, and then slide the connector onto the pins on the
intercom station.
3.3
Connections to Loudspeaker, Switches and LED
The IEB-400 use one 8-pin MTA-100 header CN2 to connect the loudspeaker, switches and LED to the printed
circuit board. The pin assignments for the header are as follows.
