Northern UTA220/UTA220k - Manual (Page 20)

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UTA220/UTA220k
Introduction
LED Description
The UTA220 has six LED indicators: B1, B2, D, DP, T, PW.
The functions of these LEDs are as follows:
B1 - On when the B1 channel has a call.
B2 - On when the B2 channel has a call.
D - This LED is for the D-Channel.
• It is off when the U connection is not established.
• It single blinks when the U connection is established.
(This may take up to 15 seconds after connection is made.)
• It double blinks when communications are established with
the switch.
• It is on when all B channels are available.
DP - On when the D-Channel is available for packet
calls.
T (Test) - On during the following global tests:
• 2B+D loopback
• Switch initiated tests--quiet mode and insertion loss
measurement
PW - On when the UTA220 has power.
FUNCTIONAL
The UTA220 operates on the ISDN Basic Rate Interface (BRI)
(2B+D). This interface provides two 64-kbps full-duplex
bearer (B) channels for circuit switched lines. The Basic Rate
Interface also provides a 16 kbps delta (D) channel for
signaling messages. The UTA220 adapts any data terminal to
the ISDN Basic Rate Interface for circuit-switched data.