Optelecom 9525AY/SM-FC User manual

Optelecom 9000 Series
Installation and Operation Manual
Model 9525AY
Single Fiber Dual Optics RS232, RS422, or
RS485 Drop and Insert Modem
UM50236, Manual 9525AY, Rev. B

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Table of Contents
Section Page
Safety Instructions 4
1 - INTRODUCTION 5
1.1 General description 5
1.2 Physical Specification 6
1.3 Environmental Specification 6
1.4 Functional Specifications 6
2 - INSTALLATION 9
2.1 System Architecture 9
2.2 Modes of Operation 13
2.3 Operational Features and Considerations 15
2.4 Set-Up Procedures 18
2.5 Mounting 19
2.6 Optical Cabling 20
2.7 Electrical Cabling 21
2.8 Power Wiring 23
3 - OPERATION 24
3.1 Turn on Procedure 24
3.2 Indicator Light Interpretation 24

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Safety Instructions
NOTE 1 THIS PRODUCT CONTAINS A CLASS 1 LASER OR LED FIBER OPTIC EMITTER. THE FOLLOWING
SAFETY PRECAUTIONS APPLY.
WARNING: Do not disconnect the fiber optic connector while the unit is powered up. Exposure to Class I
invisible optical radiation is possible when the internal fiber optic connector is disconnected while the unit is
powered up.
All Laser versions have one of two DANGER labels, shown below, found on the front panel and on the edge of
the circuit card containing the laser, near the fiber optic connector.
DANGER
Invisible Laser Radiation
When Open AVOID DIRECT
EXPOSURE TO BEAM.
CAUTION: Using controls, making adjustments or performing operations other than those specified may
result in hazardous radiation exposure. Exposure for only seconds may cause permanent eye damage as well
as other injuries.
NOTE 2 This assembly contains parts sensitive to damage by electro-static discharge (ESD). Use ESD
precautionary procedures when touching, removing or inserting parts or assemblies.

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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).

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Table 1 - Models Available
MODELS
OPTIC
PORT
FIBER
Emitter Wavelength
OPTICAL
BUDGET
TX1/RX1
TX2/RX2
9525AY/SM-ST
ST
09/125
1310 nm
1550 nm
26 dB
9525AY/SM-FC
FC
09/125
1310 nm
1550 nm
26dB
1 Range based on 0.5 dB/km at 1310 nm and for 9/125 um fiber. Range includes a 3 dB safety margin.
2Substitute 9521 for 9525 to order the rack mount card version.
1.2 Physical Specification
DIMENSIONS
Height
Width
Length
INCHES
1.5
3.17
5.0
WEIGHT
0.81 lb.
0.37 kg
INDICATORS
POWER, TD/TX1, RD/RX1, RTS/TX2, CTS/RX2, TDEXP/RX1
PRIORITY, RDEXP/RX2 PRIORITY, and FAULT.
1.3 Environmental Specification
TEMPERATURE
Fahrenheit
Celsius
Operating
-40 to 165° F
-40 to 74° C
Storage
-40 to 185° F
-40 to 85° C
HUMIDITY
0 to 95% RH noncondensing
1.4 Functional Specifications
1.4.1 OPTICAL
Wavelength 1310 and 1550 nm
Minimum coupled power into: 9/125 μm -10 dBm Peak
Receiver input power for 19-9 BER:
Minimum -36 dBm peak
Maximum -8 dBm peak
1.4.2 ELECTRICAL (Tx and Rx)
Data Interface RS232, RS422, or RS485 (2- or 4-wire), switch selectable
Connector DB25S (Primary Port)
RJ45 (Expansion Port)

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1.4.3 SYSTEM PERFORMANCE
Data rates 150, 300, 600, 1.2k, 2.4k, 3.6k, 4.8k, 7.2k, 9.6k, 14.4k,
19.2k, 28.8k, 38.4k, 57.6k, and 115.2k baud (auto baud)
BER 10-9
Re-timing accuracy 0.02% of pulse width for repeated signals
Electrical anti-streaming timeout selections
DISABLED, 4, 8, 16, 32, and 64 sec
1.4.4 ALARM
Contact Rating 15 VDC @ 15 mA
1.4.5 POWER
Operate 9 to 14 VDC @ 230 mA
Standby 9 to 14 VDC @ 180 mA
Optional 110 VAC Adapter TKH Security USA Model 9014PS
Recommended external battery 6 VDC, 4 Amp hour, PowerSonic Model PS640WL or equal, for up
to 20 hours backup @ 20° C). Battery temperature range is
–20° C to +50° C.

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FIGURE 1—9525AY DIMENSIONS

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2 - INSTALLATION
2.1 System Architecture
The Model 9525AY can be configured into three basic network architectures with almost unlimited
variations. Typically the rack mountable Model 9521Y is used at the central hub. The standalone
Model 9525AYs are used at the remote (local) locations. However, either modem can be used in either
installation if so desired.
To use the modems to serve various functions in the network they may be configured into one of four
operating modes, characterized mainly by the internal signal routing within the modem among the
electrical RS232 and expansion ports and the two optical transmitter/receiver ports.
In addition to the routing of the data signals within the modem that characterizes its mode of
operation, there are several other operational features that are important to know. Some of these
features are inherent, some are optional, and others are absent depending on the mode of operation.
In the following sections 2.1, 2.2, and 2.3 these operational features, the four modes of operation, and
the three basic network architectures and their variations are discussed in detail.
The Model 9525AY can be configured into three basic architecture types with almost unlimited
variations. They are:
a) Daisy Chain with one master controller
b) Daisy Chain with two master controllers
c) Fault Tolerant Counter Rotating Ring
The following sections describe these in detail.
2.1.1 Daisy Chain Mode with One Master Controller (Refer to Figure 2)
With this architecture, one master controller lies at the end of one or more main trunks, if you define a
main trunk as a daisy chain that roots at the master controller. In all cases, a Model 9525AY set in
Master Daisy Chain Mode will be used as the master modem. A number of 9525AYs can be connected
together to form multiple trunks by running a cable from the expansion port of the first modem to the
RS232 port of the next and so on. The section on wiring the expansion port (2.7.3) gives a schematic
diagram of the cable used in connecting the expansion port to the next modem.

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FIGURE 3–MULTIPLE DAISY CHAIN TRUNKS WITH ONE MASTER CONTROLLER

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The same cable and the Model 9525AY may be installed into the expansion port of any modem along
the trunk in order to establish a single or double branch from that trunk. Additional branches can be
made off of these branches, etc., without limit.
NOTE: IN ALL THESE INSTALLATIONS, THE TX1/RX1 PORT WILL BE CONNECTED TO THE FIBER
GOING UPSTREAM TO THE CONTROLLER AND THE TX2/RX2 PORT WILL BE CONNECTED TO THE
FIBER GOING TOWARDS THE FAR END OF THE TRUNKS OR BRANCHES.
2.1.2 Daisy Chain Mode with Two Master Controllers (Refer to Figure 3)
WARNING
This configuration may not operate in some systems. In this
Configuration each master will be able to receive polls from the
other master. The User's software must be able to recognize
and ignore such polls. If it cannot, use the TKH Security USA Model
9522 or 9526 dual master, drop/insert modem
With this architecture, master controllers lie at each end of one or two main daisy chain trunks. In this
application the local modems in the "daisy chain" trunk operate in Local Fault Tolerant mode because
the daisy chain operates in both directions. In a two-trunk installation, the Model 9525AY operating in
Master Fault Tolerant mode would be used as the master modems.
In this architecture one master transmits down two trunk fibers via both ports, through all modems in
each daisy chain, to the optical ports at the second master modem. The priority select circuitry in the
receiving modem decides which incoming optical signal to select. The local modems on each trunk will
be 9525AYs in Local Fault Tolerant mode. Each modem can receive data from either master and
transmits to both masters at either end of both trunks. If communication is lost to one master the
modem can communicate with the second.
Unlimited daisy chain branches maybe connected to either trunk.

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FIGURE 4–FAULT TOLERANT RING WITH DAISY CHAIN BRANCHES

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2.1.3 Fault Tolerant Redundant Ring
With the architecture of Figure 4, all modems are arranged along a dual fiber ring, starting with the
master controller modem (operating in Master Fault Tolerant mode), looping through an indeterminate
number of local terminal modems (operating in Local Fault Tolerant mode), and terminating back into
the second set of optical ports of the master controller modem, completing the ring.
In this architecture the master modem transmits data in both directions around the ring and receives
its own signal. The ring is terminated at the master modem. In other words, the data is not repeated
by the master modem, but ends there instead.
Each local modem in the ring transmits its input data in both directions, receives from both directions,
and re-times and retransmits the data received by the optical receivers in both directions. Each local
modem, receiving data from the master from both directions around the ring, will select the data that
arrives first and output that signal on the RS232 port (RD). If the transmission is interrupted in that
direction, the modem will automatically select the data from the other direction. The master modem
also receives data from both directions from each of the local modems, and selects the first arriving
data in the same manner.
Using the expansion port on any of the local modems, the network can be branched outin anydirection
using a non-fault tolerant daisy chain. Unlimited daisy chain branches may be connected to the fault
tolerant ring.
2.2 Modes of Operation
To set up a modem into one of its four operating modes, the user selects one of four combinations for
switch sections 1 and 2 of the MODE dipswitch.
These four modes are characterized by the specific signal routing within the modem and the availability
of the various operational features such as the expansion port, anti-streaming and fiber activity CTS
inhibit. Figures 4 show the signal routing within the modem and the available operational features for
each of these four modes. The following sections include a detailed description of each mode and
Figure 4.
2.2.1 Master Daisy Chain Mode In this mode a TD input to the data port is transmitted out via the TX2/RX2
optical port and out the expansion port as RD in RS232 format. With the INDICATORS
mode switch in the up position, a TD input will cause the TX1, TX2 and RD indicators to illuminate.
Conversely, an optical input via the TX2/RX2 optical port or an RS232 level input via the expansion port
will be output via the DB25 port as RD.
In this mode, priority select is notused. This mode is normallyused in a network withnumerousmodems
in local daisy chain mode, where the master can actat the head of two separate daisy chains (ormore,
if the expansion port is used).

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FIGURE 5–INTERNAL SIGNAL ROUTING FOR EACH MODE
2.2.2 Local Daisy Chain Mode
In this mode, there is a specific "upstream" and "downstream" data direction, because data is only
transmitted to or from the master and not both directions on a ring. Specifically, the TX1/RX1 port
communicates upstream to the master controller and the TX2/RX2 port communicates downstream to
the next modem on the daisy chain. The local daisy chain mode is not fault tolerant. Optical data
received from the master via TX1/RX1 is re-timed, retransmitted downstream via the TX2/RX2 port and
output as RD on the data port. Anti-streaming on the TX1/RX1 port is disabled because it would serve
no purpose. Optical data received from the next modem downstream via the TX2/RX2 port is re-timed
and retransmitted upstream to the master controller via the TX1/RX1 port. Data received via the
expansion port input TDE from a modem feeding a branch, and from the TD input of the data port are
ORed with the data from the TX2/RX2 port to be transmitted back to the master via the TX1/RX1 port.
Anti-streaming is an option on the TX2/RX2 port in this mode.

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2.2.3 Master Fault Tolerant Mode
This mode is virtually the same as the master daisy chain mode explained in Section 2.2 with these
exceptions: Because this is a fault tolerant mode, data will normally be received via both optical ports,
skewed slightly in time of arrival. Therefore, in this mode the priority select circuitry is employed to
choose only the data that arrives first. Secondly, the expansion port is not available in this mode.
2.2.4 Local Fault Tolerant Mode
This mode is used for all the local modems serving the many terminals around a fault tolerant dual
fiber counter-rotating ring. In this mode optical data received via both optical ports is selected based
on the earliest arrival (see Priority Select, Section 2.1.4), and routed to the RD output of the data port
and the RD output of the expansion port.
Optical data received via TX1/RX1 is re-timed and re-transmitted via TX2/RX2. Optical data received via
TX2/RX2 is re-timed and re-transmitted via TX1/RX1. These functions serve to regenerate and repeat data
traveling both directions on the dual optical ring. Data input via either TD on the RS232 port or TDE on the
expansion port is ORed and transmitted in both directionson the dual fiber ring.
2.3 Operational Features and Considerations
In addition to the signal routing that characterize each mode of operation (Section 2.2) the following
features of operation are incorporated as either basic indispensable functions or as performance
enhancements.
2.3.1 Electrical Side Anti-Streaming (RS232 mode only)
The electrical side anti-streaming feature, when enabled, limits the time that a terminal unit may
transmit data with a single request-to-send (RTS) enable. This feature is designed to prevent a
terminal unit from monopolizing the network if a terminal unit fails in a mode causing continuous
transmission. When an RTS is given to the 9525AY modem, the RS232 side anti-streaming counter is
armed. When data transmission begins the timer begins, allowing the terminal to transmit data for a
period of time up to the time-out limit. When the terminal unit stops transmitting it immediately sets
the RTS low, resetting the timer. If the terminal stops transmitting but fails to retract its RTS, the input
will be shutdown, the CTS will be disabled, and the FAULT indicator will illuminate. If the unit has
already ceased data transmission, however, the only effect on the system will be that the FAULT
indicator will illuminate. If the terminal continues to transmit data to the modem past the timeout
period, the transmission from the modem will cease, the CTS will go Low, and the FAULT indicator will
illuminate.
To use this feature an active RTS signal is required. Since a high RTS is required to transmit data via
the RS232 port, a terminal without a software controlled RTS control line must have the RTS input to
the 9525AY modem held high at all times. This can be done by connecting RTS to the DSR output
(pin6) of the modem. In this case, the RS232 side anti-streaming feature must be disabled. Mode
switch numbers 1, 2, and 3 allow the user to select one of 7 timeout periods, or disable the feature.
To select a timeout, calculate the longest transmission burst expected by the terminal and pick the
next highest timeout period. If this is not practical in your system, just disable it.

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2.3.2 Optical Side Anti-streaming
The optical side anti-streaming feature, when enabled, disconnects an optical receiver from the circuit
in the event that the receiver's output goes high for a period longer than would be expected in normal
data flow. This may occur due to a receiver failure, a transmitter or terminal equipment failure, or if
the receiver input is left open to strong ambient light (850 nm versions only). In cases where more
than one receivers' outputs are routed to the data output (RD) or in cases where a receiver's output is
re-transmitted, a failure of this type could disable one modem, part of the network, or the whole
network, depending on the network architecture, if it were not for the optical anti-streaming circuitry.
The circuit works as follows: As long as the data is high (optical power present at the receiver) the
timeout proceeds. Whenever the data goes low, as it does for all normal zeros, the timeout resets. As
long as the data does not contain a long string of continuous ones that exceeds the timeout period,
the anti-streaming will not be triggered. If there are too many ones in a row or if there is a failure
which leaves the receiver output constantly high, the receiver output will be disconnected from the
circuit and the FAULT indicator will illuminate. Mode switchnumbers4 and 5 allow the user to select
among 3 timeouts or to disable the feature. The longest timeout selection is sufficient to not trigger an
optical side anti-streaming timeout for continuous 8 bit ASCII characters ("quick brown fox") at only
150 baud. Faster data rates allow the use of a shorter timeout.
2.3.3 Clear to Send Inhibited by Optical Side Activity (RS232 mode only)
Another optional feature, enabled or disabled by mode switch number 6, causes the disabling of the
Clear-to-send (CTS) control line output in the presence of fiber side data activity. Normally the system
software will preclude such an occurrence, but as a safeguard this feature will prevent a terminal from
interfering with data already travelling on the optical highway, data either from the master or from
another terminal. The data activity detector has a fixed timeout of about 12 msec, which is sufficient to
keep CTS disabled during zeros in the fiber side data transmission at rates greater or equal to 600
baud. For ASCII character transmission at rates below 600 baud, this feature should not be used.
There is no visual indication of the feature; only the electrical CTS output's going low if already high or
being delayed in going high if there is optical side activity at the time a RTS is given.
PLEASE NOTE: IF THIS OPTION IS ENABLED, A TERMINAL WILL NOT BE ABLE TO RESPOND TO
DATA TRANSMITTED EVEN TO ITSELFUNTIL AFTER THE 12 msec TIMEOUT PERIOD. THEREFORE IT
IS NOT RECOMMENDED TO USE THIS OPTION UNLESS IT MAKES SENSE FOR YOUR SYSTEM.
2.3.4 Priority Select Priority Select is enabled automatically in both Master and Local Fault Tolerant modes
(see Sections 2.2.3 and 2.2.4). The priority select circuitry automatically selects the data that arrives
first, via optical port 1 or 2. In normal operation, since the master transmits both directions on the
ring, each terminal on the ring will receive data from both directions. The optical signal that arrives
first will be selected by the priority select circuitry, and output via the RS232 ports as RD and
RDE. If the data transmission in the first direction fails it will automatically select the data coming from
the other direction the next time it is transmitted.
This feature functions as follows: A flip flop constantly stores which optical receiver has priority, as
indicated by the RX1 and RX2 priority indicators observable with mode switch #4 in the DOWN position.
This flip flop will change states and select the other optical input port upon the arrival of data only if
there is no activity currently detected on the first port. For a period of approximately 12 ms after a
transition from HIGH to LOW on the selected optical input late arriving data from the other port is

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prevented from seizing the priority. This feature will allow guaranteed priority for the shortest
transmission path around the ring as long as the propagation time around the ring is less than 12 ms.
This is equivalent to a ring 500 km long with 500 repeating modems in the path. In the event of a
failure of the data path with has current priority, a wait of at least 12 ms must occur before the other
transmission path is selected.
NOTE: When operation in Master Fault Tolerant mode in a ring architecture, the unit is transmitting in both CW and CCW
directions simultaneously. It also receives its own transmitted data from both the CW and CCW directions. If both fibers in the
ring are routed together, as they are if they share the same cable, the times of arrival of the received signals at the two
receivers may be too close for the priority select circuitry to resolve (<150 nsec). This will cause the priority select to switch
back and forth at random which is unacceptable. To solve this problem the installer may have to add up to 100 feet of
additional fiber to one and only one of the four fibers terminating at this unit.
2.3.5 Data Re-timing
All data received via an optical port is re-timed prior to being sent on to its destinations within the
modem. This is to say that the pulse width distortion is reduced to virtually zero. This feature allows
virtually unlimited repeating avoiding the accumulation of pulse width distortion caused by the optical
transmission.
The circuit outputs pulses which are integer multiples of 8.6805556 µsec. in length, accurately re-
timing all data streams operating at bitrates of
10
6
N (8.6805556)
For 9.6 kbaud, N=12. For 57.6 kbaud, N=2. If your system operates at a nonstandard bitrate, contact
the factory. A change in crystal frequency is all that may be required.
2.3.6 Expansion Port
There is a 6-pin modular RJ-12 expansion port that has an RS232 compatible input and output. A
modem with single or dual optic ports can be attached hereto branch in one or two additional
directions. The use of this expansion port allows the user to configure a daisy chain system with
unlimited branches or a fault tolerant ring with unlimited non-fault tolerant branches. See examples in
Section 2.3.
2.3.7 Operating in RS485 2-Wire Mode
When operating in RS485 2-wire mode it is possible to have the electrical data corrupted due to the fact
that the transmit data input and received data output occurson the samepair of wires. To resolve this
problem, there is a circuit that prevents the output of received data onto the 2-wire RS485 bus within a
given period after the data input stops. This is called the Ring Propagation timeout. Refer to Table 2 to
select the proper timeout. The user can select a timeout period of 1 ms, 4 ms, or 12 ms by setting switch
positions 7 and 8. The requirementis that a setting be selected which is greater than the time it forthe data
to propagate over the fiber and through all the units around the ring, back to the master unit. The result
is,then, that the transmitted datawillarrivebackatthe receiver after its trip around the ring before the Ring
Propagation timeout has been completed, preventing the received data from corrupting the transmitted
data. It is suggested that in order to not artificially limit the polling rate that the 1 mstimeout be selected
when operating in all modes otherthanthe MasterFault Tolerant mode.

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2.4 Set-Up Procedures
The Model 9525AY has an 8-position and a 10-position dipswitch accessible via the rear panel.
Program each of these switches upon installation as required for your chosen network configuration
and feature set. Note that all optional operational features controlled by the TIMEOUT dipswitch are
disabled when switches 1 through 6 are in the down position. It may be to the user's advantage to
construct and test a mini version of the network in a lab setting to become familiar with its operation
and the operation on all the operational features prior to beginning field installation.
2.4.1 TIMEOUT Dipswitches (Refer to Table 2.0)
The eight individual TIMEOUT switches allow the user to disable or select the timeouts for both the
optical side anti-streaming feature (see Section 2.3.2) and the RS232 side anti-streaming feature (see
Sect. 2.3.1) as well as to enable or disable the "Fiber Activity CTS Disable" feature (see Sect. 2.3.3).
To disable all three, all 6 switches will be down. Chose specific timeouts per the following table:
Table 2 –TIMEOUT Dipswitch Settings
2.4.2 MODE Dipswitches (Refer to Table 3.)
The 10 individual MODE switches allow the user to select the operating mode, turn the optical emitters
to measure the peak output, override the indicator defeat feature while operating on backup power,
and select the user interface port data compatibility and termination:

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Table 3 –Mode and Interface Select Switches
2.5 Mounting
2.5.1
Standalone Mounting
The model 9525AY can be mounted
directly to a flat surface using the
attached mounting plate. The
mounting plate attaches to the bottom
of the unit using four screws.
Use the oval holes in the plate to
mount the unit to the flat surface.
It is best to mount the unit to a heat
conductive surface to maximize heat
transfer away from the units.
FIGURE 6–STAND ALONE MOUNTING

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2.5.2
System 9000 chassis mounting
The 9252AY can alternately be
mounted in a Model 9001 chassis.
Nine units will fit in one 9001-0
chassis, eight will fit in a 9001-1
chassis and seven will fit in a 9001-2
chassis. Remove and save the 4
screws holding the surface mounting
plate to extrusion. Attach the
9000KIT-5 to the unit using the four
corner screws that hold the rear panel
on the Model 9525AY (D shell
connector end). Then attach the units
to the chassis using the captive
screws in the plate supplied with the
kit.
FIGURE 7–SYSTEM 9000 CHASSIS MOUNT
2.6 Optical Cabling
2.6.1 GENERAL
The Model 9525A communicates over two fibers: one fiber for the transmit/receive signal in one
direction and a second fiber for transmit/receive in the other direction.
Most cable manufacturers identify the individual fibers in the cable. Check the fiber and mark it to
ensure that the fiber connected to the TX1 and RX1 port of the modem at one end is the same fiber
that is connected to the RX2 and TX2 port of the modem at the other end.
Before connecting the optical cable, first remove and save the plastic dust caps from the optical ports
and fiber connectors.
Remove and store the dust caps from the fiber connections. Clean the connectors with Isopropyl
alcohol on lint free tissue. Dry with bottled air.