Certifying unpinned MPO to LC multimode links with the CertiFiber Pro
This article describes a method for certifying a multimode link with an unpinned MPO connection at one end and LC at the other, often referred to as a hybrid link, using the CertiFiber Pro. Using the MultiFiber Pro will result in a quicker certification. Additionally, the MultiFiber Pro automatically reports polarity. Click here to see how you can certify unpinned MPO to LC links cables using the MultiFiber Pro.
Since this method requires the use of a break out cable (pinned MPO to LC harness), the user needs to understand the desired polarity for their installation. Additionally, inspection is critical for this method to work. Without inspection, you may end up with pessimistic results. Inspection includes both the end faces of the MPO and LC connectors. MPO adapter tips are available for the USB FI-7000 FiberInspector:
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Ask your cabling vendor/consultant for their test limits. Here we shall use TIA-568.3-E Multimode with a 2 Jumper Reference. You may have been told; "Never carry out a 2 Jumper Reference for link testing". However, this is one occasion where we will eventually end up doing just that. Note that the No. of Connections/Splices: 3/0, this is IMPORTANT. If you leave this as 2/0, your calculated loss budget in CertiFiber Pro will be optimistic by one connection - you will end up failing good links.
- Inspect all test cords and clean if necessary.
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Connect the main and remote units with hybrid SC to LC test reference cords. (Do not use Bend Insensitive Multimode cords here)
- From the HOME screen, tap SET REF > OK > SKIP WIZARD > SET REFERENCE (DO NOT USE the RUN WIZARD for this method)
- Press the HOME key.
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With the reference complete, disconnect from the INPUT PORTS only:
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Insert a known good LC to LC test reference cord into the INPUT port on the main unit:
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Insert a known good cord LC to LC test reference cord into the INPUT on the remote unit:
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Connect the main and remote units with a singlemode rated LC bulkhead adapter: (Singlemode typically provides better alignment, important for this TRC check)
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Press TEST and ensure the reported loss is ≤0.15 dB. Do not proceed otherwise.
IGNORE the number of connectors shown on the screen here. Just ensure the loss on both fibers is ≤0.15 dB. In this example, the losses are 0.05 dB and 0.04 dB, so we can proceed to the next step. -
With a reported loss of ≤0.15 dB for both fibers, press the HOME key and SET REF > OK > SKIP WIZARD > SET REFERENCE to complete a 2 Jumper Reference:
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With the reference set, press the HOME key and disconnect the main and remote units:
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Connect your pinned MPO to LC breakout cable to the main unit:
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Connect to the link you wish to test, paying attention to polarity. Press the TEST key:
Additional information
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Your result will have shown three connections on the screen, but one of them is greyed out since you referenced that out when carrying out the 2 Jumper Reference. However, only two of them are encircled with a dotted line, indicating a two connection count, not three, since a 2 Jumper reference was carried out before the measurement.
