Drop-And-Insert Mode Tests - Coastcom D/I Mux III System User Manual

Drop-and-Insert Mode Tests

Use these procedures when installing the D/I Mux III multiplexer for drop-and-insert operation.
D4 channel banks, or D/I Mux IIIs in channel bank mode, are required at both ends of the T1 links
to perform these procedures. The alarm function tests require a jackfield.
Note: Single channel bank mode testing should be performed prior to drop-and-insert mode testing.
Bypass Relay Test
Perform the bypass relay test while the system is in drop-and-insert mode. The bypass
relay test works only with the Dual DSX-1 Interface.
1. Ensure the D/I Mux III has valid T1 inputs for both T1-1 and T1-2.
2. Configure the D/I Mux III for drop-and-insert mode. Make certain the network has
one timing master source, with one locally/internally timed and one channel bank loop
timed.
3. Shut off the AC power supply. The two other channel banks or multiplexers in the link
should not go into alarm, and communications should continue between the two. If
an alarm condition arises, the Dual DSX-1 Interface should be replaced. (The slot
card alarm LEDs may flicker on the channel banks while the drop-and-insert shelf
goes into bypass.)
4. Turn the power back on. The CCU/MCU performs the initialization/restore sequence,
then reinserts itself back into the T1 path. The channel banks at the other ends of the
T1s will not operate momentarily, but will then restore themselves to normal
operation.
Chapter 5. Diagnostics
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