Insertion Loss testing of Passive Optical Splitters (POS) using OLTS

Applies to

FTBx-945 & MAX-945 OLTS


Insertion Loss testing of Passive Optical Splitters (POS) can be performed individually for validation and/or when installed as a unit in a Passive Optical Network (PON) using 945 series OLTS units, but there are some points to be aware of which are described below.


The Fiber Certifier model Certification Standards allow the characteristics of optical links to be specified using 'Link Definition' settings.

These provide thresholding values used for certification of cabling and/or applications, but are not applicable to networks integrating Passive Optical Splitters (indeed not even listing 'Splitters' as an element) and so should not be specified in this scenario.


1. Dynamic range

The overall loss of the PON being tested must not be greater than the dynamic range of the OLTS.

For both 'Telco' and 'Fiber Certifier' models, typical allowable loss ranges are:

multimode fiber: 20dB (850nm)

simplex singlemode: 45dB (1550nm)

duplex singlemode: 50db (1550nm)

Consult the appropriate specification sheet for further details.

Note: Link ORL measurements at the OLT will be impacted when testing through POS because of reflectances from each constituent fan-out splitter branch.


2. Loss thresholds

For both 'Telco' and 'Fiber Certifier' models, when testing networks with POS elements, the Pass/Fail thresholds should be configured by the user according to the requirements of the link and the overall loss expected.

When testing PONs using 'Fiber Certifier' units, a custom Test Configuration is required specifically using 'Fixed link loss thresholds' to avoid the FasTest failing due to the IL measured across POS/s.