D-Link KX-TDA100 - Manual (Page 131)

2.6 Installation of the Other Cards
Installation Manual 131
Connection Diagram for External Sensor
Power to the external sensor is provided from the EIO4 card and must be grounded through the EIO4 card
as indicated in the diagram below. A pair of "sensor" and "common" lines are connected to the EIO4 card
for each external sensor. The Hybrid IP-PBX detects input from the sensor when the signal is under 100
Ω.
External Sensor
sensor
common
I/O
EIO4
OPB3
Hybrid IP-PBX
+5V
+5V
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