Specifications

Chapter 4 4-Wire E&M/TO Configuration
4-6
2 1
4
3
-48V -48VGND GND
DETC
DETC
6
5
DETR
J1
J2
GND
10 911 8
DRR
-48V
7
GND Relay
DRVDRV' DRV'
DRV'
J3
Figure 5-4. Jumper Switch Configuration
Note: The jumpers do not change the actual interface pin assignments for the E&M signaling line
connector. The detector and driver functions always stay on the same pinouts.
DETECTOR CONFIGURATION
Jumper 1 is used to select options for configuring E&M signaling types I, II, IV and V. This jumper
connects the detector to -48 Vdc or ground. It is also used to connect the Detector Return to -48 Vdc or
ground. An on-hook signal from the far-end equipment does not cause current to flow through the
detector. When the far-end equipment applies an off-hook signal, current flows in the detector, causing
the detector to be grounded. The processor receives this information and sends E&M signaling bits to the
T1 line. The table below summarizes the signaling bits sent for both detector states: