scope:

This part of 61280 establishes preferred measurement principles and practices to assure that meaningful data describing the optical loss performance of installed cable plants can be obtained. It is not intended for component testing, nor does it define those elements of an installation that need to be measured. Establishment of requirements for installation, maintenance, repair or conformance testing is left to the specifier of this test method. This procedure is a specific test associated with IEC 61281-1. This procedure can be used to measure the optical loss between any two passively connected points, including end terminations, of a multimode optical fibre cable plant. The optical fibre cable plant, as the term is used here, may consist of optical fibre cables, connectors, mounting panels, jumper cables, and other passive components, but may not include active components. An example of a cable plant could be a portion of a LED (light emitting diode)- based local area network. This could include optical switches or couplers, but would exclude gain elements in the connected path. The accuracy of this test method depends upon proper selection of the test methods contained herein and other factors. Refer to Annex B for additional information. This test method utilizes test jumpers to facilitate a field measurement that includes all loss elements within the cable plant. It may, therefore depending on the method chosen, include connection losses that do not appear in method B of IEC 60793-1-40 - insertion loss technique (for fibres).