Black Box ME280A-35, Руководство пользователя

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20
SHM-768K
Table 3-1. Interface Signal List (Female Connectors) Pins and
Standard Signal Names (continued).
V.35 EIA-530 X.21
Signal DB25 34-Pin DB25 DB25 DB15 Description
Function Frame Standalone Standalone Frame Standalone
Pin Circuit Pin Circuit Pin Circuit/
(Function)
Remote 21 h 21 RL A control signal
Loopback input; when on,
commands the
SHM to send a
remote Loop-
back command
(V.54 Loop 2) to
the remote SHM
Test 25 k 25 TM A control signal
Indicator output from the
SHM; positive
during any test
mode.
3.4.3 S
TRAP
S
ELECTION
When the electrical installation has been completed and checked, determine
the required configuration of the SHM-768K and position the straps
accordingly. The strap locations on the PCB Layout Diagram (Figure 3-2)
correspond to the numbers listed under the “Strap Identity” column in Table
3-2.
3.4.4 I
NSTALLATION OF
I
NTERNAL
J
UMPERS AND
S
WITCHES
• Disconnect the power cable from the AC outlet.
• Release the drawer on the unit by unscrewing the two rear panel screws.
• Use the screws to withdraw the unit drawer.
• Adjust the jumpers and switches as required.
• Replace the unit drawer and tighten the screws.