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CHAPTER 4: Installation
4. Installation
Once the Sync SHM-NPR is properly configured, it is
ready to connect to your system. This section tells you
how to properly connect the Sync SHM-NPR MP to the
twisted-pair and RS-232 interfaces, and how to operate
the unit.
4.1 Connection to the Twisted-Pair Interface
The Sync SHM-NPR supports data-only communication
between two RS-232 devices at distances to 11 miles
(17.7 km) and data rates to 19.2 kbps. There are two
essential requirements for installing the Sync SHM-NPR:
1. These units work in pairs. Therefore, you must
have one Sync SHM-NPR at each end of a
two-twisted-pair interface.
2. To function properly, the Sync SHM-NPR needs
two twisted pairs of metallic wire. These pairs
must be unconditioned, dry metallic wire, between
19 and 26 AWG (the higher number gauges may
limit distance somewhat). Standard dial-up
telephone circuits, or leased circuits that run
through signal equalization equipment, are not
acceptable.