Class Fa testing to 1 GHz

ISO/IEC 11801 Amendment 2 contains a new classification of cabling system called Class F_A. This is a cabling system rated to 1,000 MHz (1 GHz). The immediate concern is whether the DTX CableAnalyzer can test this new Class F_A. To answer this, we'll look to what the standard states. ISO/IEC 11801 Amendment 2 defers testing requirements to IEC 61935-1.

In IEC 61935-1 we see the following text:

6.7 Accuracy performance requirements for Level IV field testers over 600 MHz
The Level IV requirements shall apply to measurements of class F_A cabling up to 600 MHz and pass/fail evaluation criteria shall apply. Measurement data over 600 MHz shall be provided for information only. Detailed requirements over 600 MHz are for further study.

Accuracy becomes a real issue above 600 MHz for field testing. At 1,000 MHz, the Insertion Loss accuracy is going to be at least +/- 6 dB. The cabling industry will not accept this level of inaccuracy. At the last IEC 61935-1 meeting, no field test equipment manufacturer came forward with an accuracy proposal above 600 MHz for Permanent Link testing.

Level IVe
There is no such thing, not even in any draft standard.

In the current code for the DTX CableAnalyzer, Class F_A has been added to the tester. The limit will stop at 600 MHz as per IEC 61935-1. However, the measurement will continue to 900 MHz for Insertion Loss, ACR-F/PS ACR-F and 800 MHz for all other parameters.

There are currently two connector choices (both are screened) for Class F and Class FA:

Siemon TERA
The TERA solution is a non-RJ45 connector. Advantages include dramatic improvement in NEXT (Near-End Crosstalk) and Return Loss. Both Permanent Link and Channel Adapters are available from Fluke Networks for testing the TERA solution. Customers have reported a high success rate of passing Class F with this product. It is now being licenced to Siemon's competitors such as AMP/TYCO to help gain wider acceptance.

Part Number: DTX-TERA
(This is the kit containing two DTX-PLA011 TERA Permanent Link Adapters and two DTX-CHA011 TERA Channel Adapters)

Please do not try and buy the individual components
To set a reference between the main and remote unit, you will need both a Permanent Link Adapter AND Channel adapter or the DTX-REFMOD. If you purchase just the Permanent Link Adapters, you will not be able to use them until you obtain either a TERA Channel Adapter or the DTX-REFMOD.

Nexans GG45
The GG45 is an RJ45 style solution; claimed to be backward compatible with existing RJ45 patch cords. A Channel Adapter and Permanent Link has been approved by Nexans. We recommend buying the kit, part number DTX-GG45-KIT which contains two DTX-CHA012 GG45 Channel Adapters and two DTX-PLA012 GG45 Permanent Link Adapters. You must have at least one DTX-CHA012 Channel Adapter to allow you to set a reference measurement. The DTX-CHA012 uses the Bel Stewart ARJ45 connector.