Nortel NT1R20, Description

Page: 93 / 316

NT1R20 Off-Premise Station Analog Line Card Page 69 of 290
Line cards Description
Applications
Off-premise station application
The NT1R20 Off-Premise Station (OPS) Analog Line Card is designed
primarily to provide an interface for Meridian 1 off-premise station lines. An
OPS line serves a terminal—typically, but not exclusively, a telephone
set—remote from the PBX either within the same serving area as the local
office or through a distant office. The line is not switched at these offices;
however, depending on the facilities used, the local office serving the OPS
station may provide line functions such as battery and ringing. Facilities are
generally provided by the local exchange carrier (OPS pairs are usually in the
same cable as the PBX-CO trunks). The traditional OPS scenario
configuration is shown in Figure 20.
Note: OPS service should not be confused with off-premise extension
(OPX) service. OPX service is the provision of an extension to a main
subscriber loop bridged onto the loop at the serving CO or PBX.
Additionally, OPX as used to denote off-premise extension service
should not be confused with the OPX class-of-service assigned in the
Single-line Telephone Administration program (LD 10).
Other applications
The operating range and built-in protection provisions of the OPS analog line
card make it suitable for applications that are variants on the traditional
configuration shown in Figure 20. The following are some examples of such
applications:
— a PBX in a central building serving stations in other buildings in the
vicinity, such as in an industrial park (often called a campus
environment). Facilities may be provided by the local exchange carrier
or may be privately owned. Protection may or may not be a requirement.
— termination to other than a telephone set, such as to a key telephone
system
— individual circuits on the OPS analog line card may also be configured
as ONS ports in LD 10:
• to have ONS service with hazardous and surge voltage protection
(not available on other Meridian 1 analog line cards)
• to use otherwise idle OPS analog line card ports