Specifications

Copyright © AMETEK
25
25.1 Description
The 6NF module is used to connect IEEE C37.94
compliant devices to the FOCUS multiplexer.
This eliminates the cost and interference problems
inherent with metalic circuits. The IEEE C37.94
standard was developed specifically to interface
protective relays to communications equipment
via fiber.
The module is available for use with either 850
nm (multimode) or 1300 nm (single mode) optics.
The 850 nm version is designated (6NF) and the
1300 nm version “6NF-13”.
Typical devices you can connect to the module
include:
•External protocol converters to V.35, RS-
422, G703.2 to IEEE C37.94
• Current differential protective relays (SEL
311L, GE L90, RFL 9300)
• Contact transfer devices (SEL 2594,
INIVEN PDR2000)
Features of the 6NF module include:
• Channel Data from 8–96 bits (1-12 DS0)
• Loss of Signal Detection–Low Level
• Loss of Signal Detection–Data Errors
• Channel Recovery after 8 Consecutive
Correct Frames
• Path “Yellow” Detection
• Jitter Tolerance Exceeding ±100ns
•Maximum Wander of ±250ns
•TXLevel - 850 nm (#?) 1300 nm (future)
• RX Level - 850 nm (#?) 1300 nm (future)
IEEE C37.94 communication is synchronous with
the communication equipment. The 6NF provides
the clock signal for both transmit and receive data
streams.
25.2 Network Connection
Connection between FOCUS and IEEE C37.94
devices is made with multi-mode fiber optic cable
equipped with ST connectors. Fiber optic cable
provides electrical isolation between connected
devices and FOCUS. Use of a 6NF module with
FOCUS also eliminates interference problems
associated with metallic circuits.
25.3 Installation
As with other FOCUS modules, we recommend
that you initially install and test the 6NF module
and interface in a “test” chassis (i.e., one that is
not part of an operating network). This way, you
can quickly perform the acceptance test without
interfering with a live network. Whether you are
installing the module in a test chassis or a chassis
that is on line in a network, use the installation
procedure described here.
The 6NF module occupies one chassis slot and
one or more time slots (DS0s), depending on the
N value. Before installing the module and its
interface, make sure that:
• The FOCUS chassis is set up, energized,
and operational, with all necessary
common equipment (see Chapter 3)
• The FOCUS Configuration Software (FCS
version 3.10 or greater) has been installed
on your computer (see Chapter 3)
• Acceptance tests for the FOCUS chassis
and all previously installed equipment have
25. ANSI C37.94 (6NF) Module
NOTE
FOCUS firmware compata-
bility with the 6NF module.
MV2 N/A
MV3 ≥ 3.06
MV4 ≥ 4.11
MV5 ≥ 5.0