Cabletron Systems TRXI-24 User Manual

 

Page 2-7

 

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

 

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.

 

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.

 

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. 

Table 2-6. Multimode Fiber Optic Cable Specifications

 

50/125 

 

µ

 

m

13.0 dB or less

The maximum allowable fiber op-
tic cable length is 2 km (2187.2 
yards). However, IEEE 802.5 
specifications allow for a maxi-
mum of 1 km (1093.6 yards).

62.5/125 

 

µ

 

m

16.0 dB or less

100/140 

 

µ

 

m

19.0 dB or less