Optelecom 9525AY, Инструкция по установке и эксплуатации

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1 - INTRODUCTION
1.1 General description
The TKH Security USA Model 9525AY is an RS232, RS422, and RS485 compatible standalone fiber optic
modem with dual optics for drop and insert applications that can be configured in a wide range of
poll/response network architectures. The unit operates using only one single mode fiber for transmit and
receive in the upstream direction. A second fiber is used in the downstream direction. This results in the
formation of a single fiber daisy chain or loop.
The units may be operated in either daisy chain or fault tolerant redundant ring architectures. In addition, in
certain modes, an RS232 expansion port on the modem may be connected to a second modem with single or
dual optics to branch the network in one or two additional directions. With this capability a daisy chain
network may be set up with unlimited branches off the main trunk(s). Additionally, unlimited daisy chain
connections may be made branching off of a main fault tolerant dual fiber ring. All signals received via an
optical port and retransmitted via fiber or via the expansion port are re-timed to.01%pulse width accuracy by
a crystal controlled time-base, eliminating pulse width distortion and allowing virtually unlimited repeating.
The units have four switch selectable modes of operation: Daisy Chain Master mode, Daisy Chain Local mode,
Fault Tolerant Master mode, and Fault Tolerant Local mode. See Section 2, Installation, for a complete
description of these modes of operation.
The units have anti-streaming (sometimes referred to as anti-babbling) circuitry for both the optical fiber and
electrical (RS232) sides. On the RS232 side, when enabled, the anti-streaming limits the amount of time a
terminal is allowed to transmit data onto the network for each Request to Send. This is to prevent a faulty
terminal unit from monopolizing the network. On the fiber side the anti-streaming disables an optical receiver
in the event that the receiver output stays high longer than the maximum allowable time. This will prevent the
whole fiber network from being disabled by a continuous "on" failure by receiver or optical emitter. This
feature is not available when in RS422 or RS485 mode because the RTS line is not supported.
The units have nine LED indicators. A POWER indicator that is on solid when operating under primary power
or blinks if operating on battery backup or under low voltage from the primary power source. A FAULT
indicator illuminates in the event of either a fiber side or electrical side anti-streaming timeout. The other six
indicators serve dual functions as selected by the indicator mode switch. In one position the LEDs indicate
electrical side signal activity. In the other position the LEDs indicate fiber port activity as well as the active
fiber input port as chosen by the priority select circuitry.
A ten-position MODE dipswitch allows the user to select one of the four operating modes and optical emitter
test. In addition, an eight-position TIMEOUT dipswitch allows the user to select timeouts for (or disable)the
optical and electrical side anti-streaming, the fiber activity CTS inhibit (RS232 mode) and the electrical Ring
Propagation output disable (RS485, 2-wire operation only).
The unit operates from a 9 to 14 VDC supply. The unit contains a built in battery charger compatible with a 6
volt lead-acid gel cell battery (1.2 Amp-hour to 7 Amp-hour capacity). This battery allows from 6 to 35 hours
of emergency battery backup operation. A screw terminal connector facilitates battery connection.
The 9525AY module is optically compatible with the 9521Y card.
The package is an anodized aluminum extrusion with painted aluminum front and rear panels. An optional
mounting kit is available for mounting in a System 9000 chassis (Model 9000KIT-5).