High Resistance (HR) faults have been a bug bear of DSL based broadband for many years, and it appears that it may be easier to identify these faults, rather than the usual pattern of several engineer visits and the worry the consumer gets about a charged being raised by Openreach.
Openreach concluded a Copper Integrated Demand Testing (CIDT) trial in August, working with four providers at 119 exchanges. The results of the trial was a 96% identification rate for High Resistance faults, and the integration of the High Resistance testing into the Line Test OK diagnostic.
High Resistance faults are the result usually of joint which works well enough for voice frequencies, but performs marginally for DSL traffic, but appears to clear itself for some time after a higher current is sent down the wire, which helps to bridge a gap, displace moisture etc. For the end-user this means that the DSL service will improve after the phone rings.
The full roll-out of the testing systems is expected to be complete by the end of June 2012, and should result in less people complaining that their broadband support says their is no problem with the line as the line test reports a good line, when the user can clearly see a problem. A steady trickle of posters arrive on our forums looking for advice in this area, and the answer if the symptoms fit the pattern of a High Resistance fault has been to direct them back to their broadband support, highlighting that a High Resistance fault (frequently shortened to HR fault by Openreach) exists on the line.