Fluke OF-500 OptiFiber, Техническое справочное руководство

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Using the Loss/Length Option
Using Mandrels for Testing Multimode Fiber
6
6-15
Using Mandrels for Testing
Multimode Fiber
You should use mandrels when testing multimode fiber.
Mandrels can improve measurement repeatability and
consistency. They also allow the use of LED light sources
to certify 50 µm and 62.5 µm fiber links for current and
planned high bit-rate applications, such as Gigabit
Ethernet and 10 Gigabit Ethernet.
The gray mandrels included with some OptiFiber models
are compliant with TIA/EIA-568-B for 62.5
µ
m fiber with a
3 mm jacket. Mandrels for 50
µ
m fiber are available from
Fluke Networks. Refer to the appropriate standard for
mandrel requirements if you follow other standards.
Table 6-3 shows a partial list of mandrel requirements for
TIA and ISO standards.
Figure 6-4 shows how to wrap the fiber around a
mandrel. Place mandrels on the tester’s output fibers, as
shown in Figures 6-6 through 6-13.
In the reference and test connection diagrams shown on
the tester, mandrels are indicated by a loop in the fiber.
Table 6-3. TIA/EIA-568-B.1 and ISO/IEC TR 14763-3 Mandrel Requirements
Fiber
core size Standard
Wraps Around
Mandrel
Mandrel Diameter for
250 µm Buffered Fiber
Mandrel Diameter for 3 mm
(0.12 in) Jacketed Cable
50 µm TIA/EIA-568-B.1 7.1 5 25 mm (1.0 in) 22 mm (0.9 in)
ISO/IEC TR 14763-3 6.22 5 15 mm (0.6 in) 15 mm (0.6 in)
62.5 µm TIA/EIA-568-B.1 7.1 5 20 mm (0.8 in) 17 mm (0.7 in)
ISO/IEC TR 14763-3 6.22 5 20 mm (0.8 in) 20 mm (0.8 in)