DH+/RIO OPTICAL COMMUNICATION MODULES USERS MANUAL
Copyright © 2003 by Phoenix Digital Corporation, All Rights Reserved.
corresponding Diagnostic Status Bit(s) or Relay Output(s). (Note that both ID and IF are provided
on the same indicator for 1746 OLC and 1756 OCX plug-in modules. For ID the indicator changes
between green and off, and for IF the indicator changes between red and off.)
No additional calibration adjustments will be required for the lifetime of the network installation,
unless the network characteristics are changed. Changes affecting either the optical characteristics of
the network media (media replacement, splice, new terminations, etc.), or replacement of one or
more fiber optic modules, will require that the initialization procedure be repeated for each fiber
module which has one or more
of its’ optical network receive inputs affected by the change. (The
initialization procedure may be done on-line, post installation, and will not affect real time network
data transmissions.)
Impending Fault conditions are reported by standalone, panelmount OCMs through reed relay
contact outputs on J4 connector pin #s 3,4 and 7,8... for fiber optic channel A and B respectively
(see Table 10). Impending fiber optic network fault conditions are reported by 1771 Plug-In OCMs,
1746 Plug-In OLCs, and 1756 Plug-In OCXs in the Diagnostic Status Byte (see Figures 9 and 10).
If a fiber module detects an impending communication failure on the fiber optic receive data inputs on
Channel A and/or B (due to either media failure or failure of an adjacent fiber module) it will assert the
corresponding diagnostic status bit or relay output. These bits and relay outputs may be used to
locate the precise fiber where the failure is occurring. (Note: Impending Fault Monitoring is only
available on 850 nm and 1300 nm multimode fiber optic modules.)
1.3.3.8 SIMULATE NETWORK FAULT CONDITIONS
After a fault tolerant fiber optic communication network becomes operational it is very impor-
tant to verify the network is correctly configured for fault management. This may be done by delib-
erately introducing single points of failure throughout the network and verifying communication con-
tinuity after each failure.
Fiber optic network faults may be simulated by Phoenix Digital fiber optic modules by forcing
errors on the fiber optic Channel A and B transmit outputs. This may be accomplished on 1771
OCM and 1746 OLC plug-in fiber optic modules through the Diagnostic Control Byte (see
Figure 9), and on all fiber optic modules through the Diagnostic Select Switches (see Tables 10
and 11).
1.3.3.9 LOCAL INTERFACE DISABLED
On certain occasions in it may be necessary to segment or partition the communication network in
order to isolate one or more problems on the network grid. These problems may include improper
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