Honeywell Series 8 I/O - Available Optical Power; Losses in splices

9. Series 8 I/O Link Fiber Optic Extenders (FOE)
9.4. Defining the Fiber Optic topology
R500 Series 8 I/O User's Guide 253
April 2017 Honeywell
Available Optical Power
Where for a Standard I/O Link Extender:
Transmit Power = - 16.0 dB
Minimum Receiver Sensitivity = - 24.0 dB
Power Loss Over Time = 2.5 dB
Example calculation for a Standard I/O Link Extender using 62.5 micron cable:
(- 16.0 dB) - (- 24.0 dB) - (2.5 dB) = 5.5 dB Available Optical Power
ATTENTION
As the maximum transmitter output level is -7 dB, and the maximum receiver
input level is -10 dB, the receiver may be overdriven on a short link and may
require a 3 dB attenuator. Connector allowances for the transmitter and
receiver are included in the above power declaration.
Losses in splices
The table below is used for the following Losses in Splices calculation.
Losses in Splices = Number of Splices x Maximum Loss per Splice
Standard Extender I/O
cable type
Average Loss
per type (dB)
Maximum loss
per type (dB)
Fusion
0.2
0.3
Mechanical
0.3
0.5
ST-connector
0.5
0.9
Examples: Max. span calculation for cables with fusion or mechanical splices:
Variable values: Available optical power = 5.5 dB, two splices.
Two fusion splices
(5.5 dB) - (2 splices x 0.3 dB max loss per splice) / (4 dB/Km) = 1.22 Km
Two mechanical
splices:
(5.5 dB) - (2 splices x 0.5 dB max loss per splice) / (4 dB/Km) = 1.12 Km
I/O link extender cable selection
Honeywell ST-type connector cable assemblies
Honeywell can provide short fiber optic ST-type connector cable assemblies. You can
order by part number and cable length.