Drop-And-Insert: Bypass - Coastcom D/I Mux III System User Manual

Chapter 5. Diagnostics

Drop-and-Insert: Bypass

Bypass mode removes the D/I Mux III from the T1 line by bypassing the incoming T1 PCM
around the LIUs. The Dual CSU Interface receivers and line buildouts are left in line to provide
the correct levels on the T1 line. Within the D/I Mux III shelf, the output of LIU B is connected to
the input of LIU A, and the output of LIU A is connected to the input of LIU B, as illustrated in
Figure 5-12. This allows the D/I Mux III to frame on itself, providing an internal operational check.
Figure 5-12. Drop and Insert: Bypass
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