5.2 BACK PANEL LED STATUS MONITORS
The Model 2400 also features two LEDs that are located on the
back panel. Figure 8 below shows the positions of the LEDs. Following
Figure 13 is a description of each LED.
•
RD (Receive Data) is off to indicate an Idle condition or Binary
“1” data. Green indicates Binary 0 data.
•
NS (No Signal) glows green when there is no valid carrier.
This means the Model 2400 receiver does not detect a valid
signal from the digital service provider, or, in the case of short-
haul operation, from the remote Model 2400. If NS is lit, check
for an unplugged cable, broken wire or an incorrect Line Rate
selection.
5.3 TEST MODES
The Model 2400 offers two V.54 test modes, plus a built-in V.52
BER test pattern generator, to evaluate the condition of the modems
and the communication link. These tests can be activated physically
from the front panel, or via the interface.
5.0 OPERATION
Once you have configured the Model 2400 properly (see Section
3.0) and made line, DTE and power connections correctly (see Section
4.0), you are ready to operate the unit(s). This section describes the
LED status monitors, and use of the built-in V.54 and V.52 test modes.
5.1 FRONT PANEL LED STATUS MONITORS
The Model 2400 features five front panel status LEDs that indicate
the condition of the unit and communication link. Figure 12 below
shows the front panel location of each LED. Following Figure 12 is a
description of each LED.
•
PWR (Power) glows green when power is supplied to the unit.
The unit is operational as soon as power is applied--there is
no power switch.
•
TD (Transmit Data) is off to indicate an Idle condition or Binary
“1” data. Red indicates Binary 0 data.
•
CD (Carrier Detect) glows red when carrier is active. In 64
Kbps mode, CD is off if there is no carrier. In 56 Kbps mode,
CD is off if there is no carrier, if an Out-of-Service or Out-of-
Frame violation occurs, or if idle code is detected.
•
BERT glows red when errors are detected in test mode during
the 511and 511/E tests. This indicator also glows during
normal operation to indicated framing errors and/or bipolar
violations in 64 Kbps mode, or invalid bipolar violations in 56
kbps mode.
•
LOOP glows red when the V.54 loopback tests or V.52 BER
tests are initiated or when CO loopback is initiated by the
service provider.
15
16
RD
NS
Power Jack
RJ48S Jack
Figure 13. Model 2400’s back panel LED indicators
Figure 12. Model 2400’s front panel LED indicators and test switches
TD
CD
PWR
BERT
LOOP
511/E RDL
NORMAL
511 LAL
