Cabletron Systems TRXI-24, TRXI-22 manual Multimode Fiber Optic Cable Specifications for the TPIM-F2

REQUIREMENTS/SPECIFICATIONS

2.1.4Multimode Fiber Optic Cable Specifications for the TPIM-F2

Table 2-6 shows Multimode Fiber Optic Cable specifications for the TPIM-F2.

Table 2-6. Multimode Fiber Optic Cable Specifications

Cable Type	Attenuation	Maximum Drive Distance
50/125 ∝m	13.0 dB or less	The maximum allowable fiber op-
		tic cable length is 2 km (2187.2
62.5/125 ∝m	16.0 dB or less
		yards). However, IEEE 802.5
100/140 ∝m	19.0 dB or less	specifications allow for a maxi-
		mum of 1 km (1093.6 yards).

Maximum Trunk Lengths

The maximum trunk cable length between the TRXI and another active device is equal to the maximum drive distance as shown in Table 2-6. When the neighboring token ring device is a passive device, the combined length of twice the longest trunk cable plus the longest lobe cable attached to the passive ring segment cannot exceed the Maximum Drive Distance Trunk Length.

Attenuation

The fiber optic cable must be tested with a fiber optic attenuation test set that is adjusted for an 850 nm wavelength. This test verifies that the signal loss in a cable is within an acceptable level. Table 2-6 shows the attenuation for each Multimode cable type.

Fiber Optic Budget

When determining the maximum fiber optic cable length, the fiber optic budget delay should be calculated and taken into consideration before fiber optic cable runs are incorporated in any network design. Fiber optic budget is the combination of the optical loss due to the fiber optic cable, in-line splices, and fiber optic connectors.

Page 2-7