Black Box SHM-NPR, Руководство пользователя

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CHAPTER 3: Configuration and Installation
1B. SHM-NPR/RJ (ME821 models) only: Get 4-wire twisted-pair cable and terminate
it with RJ-11 or (especially if the cable is shielded) RJ-12 plugs, using the pin
assignments shown in Figure 3-3 (for RJ-11 cable, substitute Pins 1, 2, 3, and
4 for Pins 2, 3, 4, and 5 respectively) and end-to-end wiring like that shown
in Figure 3-2 on the previous page. Also, if the cable is shielded, attach the
shield to Pin 1 or 6
on one end of the cable only . Plug the cable into the RJ-12
jacks on the units.
CAUTION!
Under no circumstances should you attach the cable shield to Pin 1 or 6
on both ends; this could cause damaging electrical “ground loops.”
Neither should you ever connect these units to the public switched
telephone system in any way. This could also severely damage your
equipment.
Figure 3-3. Wiring a cable for ME821 units.
2.
Both models:
Plug the units’ DB25 connectors into the RS-232 serial ports
on the corresponding devices and tighten the mounting screws.
That’s all there is to it. Assuming your units’ DCE/DTE switches are set properly,
your SHM-NPR or SHM-NPR/RJ system should be ready for continuous operation.
PINS
FEMALE
1 2 3 4 5 6
MALE
2 (RCV-)
3 (XMT+)
4 (XMT-)
5 (RCV+)
Unit—Pins 1
and 6 connected
to frame ground
Cable—Pin 1 or 6
connected to shield
on one end only;
for end-to-end
pinning, refer to
Figure 3-2 on the
previous page