In order to ensure accuracy it is important to set-up an OLTS correctly. Here’s how:
- Allow sources to stabilize
- Determine correct pass/fail test limits
- Set the reference correctly
- Ensure tester connectors are clean
Allow sources to stabilize
Allow sources to stabilize by turning on both the main and remote units about five minutes before starting to make any measurements. It is key to allow extra time for the sources to stabilize if the change in environmental temperature is significant. If the sources do not stabilize there will be issues with setting the reference as the source warms-up and its output power increases, resulting in optimistic or negative loss readings.
Determine correct pass/fail test limits
Establish and enter the correct pass/fail test limits for the links being tested. If you're installing SYSTIMAX links, leverage the SYSTIMAX Fiber Performance Calculator that can be found on-board the CertiFiber® Pro OLTS. By choosing it you can quickly and easily calculate maximum attenuation performance for a proposed SYSTIMAX cabling channel, know which applications the channel will support, and receive Commscope's guarantee of support-in writing.
Set the reference correctly
Set the reference correctly in order to remove the impact of the various connections between the tester and the links under test. Preferably, this should be done using the one jumper method. If reference setting is done incorrectly, undesirable negative loss measurements will typically occur. A negative loss is often referred to as a ‘gainer’ and should not be possible on a passive link. When setting the reference ensure this is done with clean, high-quality test reference cords (TRCs), as required by ANSI/TIA and ISO/IEC. Dirty or defective TRCs will result in links not passing. Keep in mind that TRCs can wear out or be damaged if not treated correctly, so always replace dust caps to
protect end-faces and do not set bare end-faces on surfaces.
Ensure tester connectors are clean
Ensuring the connectors on the test instruments themselves are clean is often overlooked and feedback from our Service Centers has indicated that a very high percentage of instruments sent in for repair were only suffering from dirty fiber optic connectors. Inspecting and cleaning instrument connectors can be carried out in the field with the very same equipment that is used to inspect and clean TRCs and connectors in patch panels.