Cabletron Systems NBR-420 사용자 설명서

•

Temperature - Multi-pair PVC 24 AWG telephone cables typically 
have an attenuation of approximately 8-10 dB/100 m at 20

°

C (68

°

F). 

The attenuation of PVC insulated cable varies significantly with 
temperature. At temperatures greater than 40

°

C (104

°

F), we strongly 

recommend using plenum-rated cable to ensure attenuation remains 
within specification.

When connecting a multimode fiber optic link segment to an EPIM-F1 or 
EPIM-F2, ensure the network meets the following requirements:

•

Cable Type - Use the EPIM-F1 and EPIM-F2 for the following 
multimode fiber optic media:

-

50/125 

µ

m fiber optic cabling

-

62.5/125 

µ

m fiber optic cabling

-

100/140 

µ

m fiber optic cabling

•

Attenuation - You must test the fiber optic cable with a fiber optic 
attenuation test set adjusted for an 850 nm wavelength. This test 
verifies the signal loss if a cable falls within the following acceptable 
levels:

-

13.0 dB or less for a 50/125 

µ

m fiber cable segment

-

16.0 dB or less for a 62.5/125 

µ

m fiber cable segment

-

19.0 dB or less for a 100/140 

µ

m fiber cable segment

•

Budget and Propagation Delay - When you determine the maximum 
fiber optic cable length to incorporate fiber runs into your network, you 
must calculate and consider the fiber optic budget (a total loss of 
10.0 dB or less is permissible between stations) and total network 
propagation delay.

-

To determine the fiber optic budget, combine the optical loss due 
to the fiber optic cable, in-line splices, and fiber optic connectors. 
Typical loss for a splice and connector (together) equals 1 dB or 
less.