Cabletron Systems 42T, MICROMMAC Single Mode Fiber Optic Cable Specifications, Fiber Optic Budget

REQUIREMENTS/SPECIFICATIONS

Fiber Optic Budget

The fiber optic delay budget, which determines the fiber optic cable’s maximum length, should be calculated and taken into consideration in the network design stage. Fiber optic delay budget is determined by summing the optical signal loss due to fiber optic cable attenuation, in-line splices, and fiber optic connectors.

2.1.4 Single Mode Fiber Optic Cable Specifications

Table 2-7 shows specifications for the Single Mode Fiber Optic Cable supported by TPIM-F3.

Table 2-7. Single Mode Fiber Optic Cable Specifications

Cable Type	Attenuation	Maximum Drive Distance
8/125-12/125 ∝m	10.0 dB or less	The max. allowable fiber optic
		cable length is 10 km (10936
		yards). However, IEEE 802.5
		specs allow for a max. of 1 km
		(1093.6 yards).

Maximum Trunk Lengths

The maximum trunk cable length between the MicroMMAC-T and other active devices is equal to the Maximum Drive Distance as shown in Table 2-7. For passive devices, the combined length of twice the longest trunk cable plus the longest lobe cable attached to the passive ring segment must not exceed the Maximum Drive Distance Trunk Length.

Attenuation

Fiber optic cable must be tested with an attenuation test set adjusted for a 1300 nm wavelength. This test ensures that the cable’s signal loss is within an acceptable range of 10 dB or less for any given single mode fiber optic link.

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