Endace DAG 4.5G2 Card, Руководство пользователя

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EDM 01-18 DAG 4.5G2/G4/GF Card User Guide
Pluggable
Optical
Transceivers
(cont)
Power Input
Note : The optical power input to the DAG card must be within the
receiver’s dynamic range of 0 to -22dBm. If it is slightly outside of this
range it will cause an increased bit error rate. If it is significantly
outside of this range the system will not be able to lock onto the signal.
When power is above the upper limit the optical receiver saturates and
fails to function. When power is below the lower limit the bit error rate
increases until the device is unable to obtain lock and fails. In extreme
cases, excess power can damage the receiver.
When you set up the DAG card you should measure the optical power at the
receiver and ensure that it is within the specified power range. If it is not,
adjust the input power as follows:
•
Insert an optical attenuator if power is too high, or
•
Change the splitter ratio if power is too high or too low.
Splitter Losses
Splitters have the insertion losses either marked on their packaging or
described in their accompanying documentation. General guidelines are:
•
A 50:50 splitter will have an insertion loss of between 3 dB and 4 dB on
each output
•
90:10 splitter will have losses of about 10 dB in the high loss output, and
<2 dB in the low loss output
Note: A single mode fiber connected to a multi-mode input will have
minimal extra loss. However a multi-mode fiber connected to a single
mode input will create large and unpredictable loss.
Pluggable
Copper
Transceivers
The DAG 4.5G2/G4 card supports industry standard Small Form-factor
pluggable (SFP) copper transceivers.
The transceivers consists of two parts:
•
Mechanical chassis attached to the circuit board
•
Transceiver unit which may be inserted into the chassis
Endace recommends that you use Cat6 copper cable. The DAG 4.5 card
copper module specification is shown below:
Part Type Data Rate
FCMJ8521C 10/100/1000 Base-T >1.25Gbps
©2005-2006 11 Version 4: August 2006