Intelligent CIO Middle East Issue 05 | Page 48

INTELLIGENT BRANDS // Cabling Class E Channel Frequency Myths and Misconceptions Taken from a recent white paper, Excel Networking separates fact from fiction and industry spin from reality. T he standards requirement In Cenelec (EN) or ISO terms each Class of Channel or Permanent link is made up by Categories of Components. The performance requirements of those components, whether cable, connecting hardware or patch cords are laid out in the general requirements of the respective Standards, namely EN50173-1: 2011 and ISO 11801: Ed 2.2: 2010. The following extract from EN501721:2011 lays out the frequency requirements for each class of channel. Examples This standard specifies the following classes for balanced cabling: a) Class A: specified up to 0,1 MHz; b) Class B: specified up to 1 MHz; c) Class C: specified up to 16 MHz; d) Class D: specified up to 100 MHz; e) Class E: specified up to 250 MHz; f) Class EA: specified up to 500 MHz; g) Class F: specified up to 600 MHz; h) Class FA: specified up to 1 000 MHz’ 48 INTELLIGENTCIO The standard then goes on to define the performance for each required measurement at these set frequencies. In the case of Return Loss the table is as follows: Additional Frequency measurement is all well and good in theory but in practice, it s \