1、 September 2008 ISO/IEC 11801 (Second edition 2002) Amendment 1 (2008) Information technology Generic cabling for customer premises CORRIGENDUM 1 Page 22 of Amendment 1 Replace the existing Table 17 by the following new Table 17: Table 17 Propagation delay for channel Class Frequency MHz Maximum pro
2、pagation delay s A 0,1 = f 20,000 B 1 0,1 f 5,000 C, D, E, E A, F, F A NOTE 1 f 5 0,002 4 0,036 0,534 + + f NOTE The equation for propagation delay applies to the upper frequency of the class. Page 24 of Amendment 1 6.4.14.4 Coupling attenuation Move the existing third paragraph from before Table 22
3、 to after Table 22: It is possible to assess coupling attenuation by laboratory measurements of representative samples of channels assembled using their component and connector termination practices. Page 25 of Amendment 1 6.4.15.1 General Replace the existing second paragraph by the following new s
4、econd paragraph: If coupling attenuation for Class E Aor F channels is 10 dB better than Table 22 or for Class F Achannels is 25 dB better than Table 22, then the requirements of 6.4.15 are met by design. 6.4.15.2 Power sum alien NEXT (PS ANEXT) Replace the last identifier by the following identifie
5、r: ANEXT l, i,kis the alien near-end crosstalk loss coupled from pair i of disturbing channel (l) to the pair k of the disturbed channel. Page 26 of Amendment 1 Table 23 PS ANEXT for channel Replace the last line of footnote bby the following line: IL 100MHz,iis the insertion loss of a pair i at 100
6、 MHz. September 2008 Page 28 of Amendment 1 6.4.15.5 PS AFEXT for Class E Achannels Replace the fourth identifier for equation 9 by the following identifier: AFEXT l,i,kis the alien far-end crosstalk loss coupled from pair i of disturbing channel (l) to the pair k of the disturbed channel; Replace t
7、he last identifier for equation 9 by the following identifier: IL l,iis the measured insertion loss of pair i of disturbing channel l. Page 29 of Amendment 1 6.4.15.6 PS AFEXT for Class F Achannels Replace the last identifier by the following identifier: AFEXT l, i,kis the alien far-end crosstalk lo
8、ss coupled from pair i of disturbing channel (l) to the pair k of the disturbed channel. Page 30 of Amendment 1 6.4.15.7 PS AACR-F for Class E Aand Class F Achannels Change the following from font size 9 to font size 10: The PS AACR-F requirements shall be met at both ends of the channel. PS AFEXT k
9、is the power sum alien far-end crosstalk loss coupled to pair k. Replace the existing Table 27 by the following new Table 27: Table 27 PS AACR-F for channel Class Frequency MHz Minimum PS AACR-F a, bdB E A 500 1 f ) ( lg 20 77 f F A 000 1 1 f ) ( lg 20 92 f a PS AACR-F at frequencies that correspond
10、 to calculated values of greater than 67,0 dB shall revert to a minimum requirement of 67,0 dB. b PS AACR-F at frequencies that correspond to calculated PS AFEXT values of greater than 67,0 dB or 102-15*lg(f) dB shall be for information only. Replace the existing Table 28 by the following new Table
11、28: Table 28 Informative PS AACR-F values for channel at key frequencies Minimum PS AACR-F dB Frequency MHz Class E A Class F A 1 67,0 67,0 100 37,0 52,0 250 29,0 44,0 500 23,0 38,0 1 000 N/A 32,0 September 2008 Page 31 of Amendment 1 Replace the existing Table 29 by the following new Table 29: Tabl
12、e 29 PS AACR-F avgfor channel Class Frequency MHz Minimum PS AACR-F avg a, b, cdB E A 500 1 f ) ( lg 20 81 f a PS AACR-F avgat frequencies that correspond to calculated values of greater than 67,0 dB shall revert to a minimum requirement of 67,0 dB. b PS AACR-F avgat frequencies that correspond to P
13、S AFEXT values of greater than 67,0 dB or 102-15*lg(f) dB shall be for information only. c The PS AACR-F avglimit for Class F A channels is equal to PS AACR-F specified in Table 27. Replace the existing Table 30 by the following new Table 30: Table 30 Informative PS AACR-F avg values for channel at
14、key frequencies Frequency MHz Minimum Class E A PS AACR-F avg dB 167,0 100 41,0 250 33,0 500 27,0 7.2.2.1 Component choice Replace the text for the last two bullets by the following: Category 6 Acomponents (under consideration) provide Class E Abalanced cabling performance Category 7 Acomponents (un
15、der consideration) provide Class F Abalanced cabling performance Page 32 of Amendment 1 Replace the existing Table 31 by the following new Table 31: September 2008 Table 31 Minimum and maximum length Segment Minimum length m Maximum length m FD-CP 15 85 CP-TO 5 - FD-TO (no CP) 15 90 Work area cord 2
16、 a5 Patch cord 2 - Equipment cord 2 b5 All cords - 10 a If there is no CP, the minimum length of the work area cord is 1 m. b If there is no cross-connect, the minimum length of the equipment cord is 1 m. Page 33 of Amendment 1 In Table 33, replace the existing NOTE 1 by the following NOTE 1: Where
17、channels contain a different number of connections than in the model shown in Figure 13, the fixed cable length shall be reduced (where more connections exist) or may be increased (where fewer connections exist) by 2 m per connection for category 5 cables and 1 m per connection for Category 6 and 7 cables. Additionally, the NEXT, Return Loss (RL) and ACR-F performance should be verified.
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