Connectix tells Data Centre Management that is more than one way of skinning the cabling cat

There has however been a steady rise in the use of preconnectorised or preterminated cabling systems whereby an installer turns up at site with a ready terminated cable assembly, lays it into position, plugs the connectors into the patchpanels and wall outlets, and leaves again.

Advantages

There are two main advantages to this; the first is reduced time on site and the second is improved quality of the terminations.
Preconnectorised cabling is most popular when time on site is at an absolute premium. This may be in a new build, such as a data centre, where time scales are critical and many different trades are vying for the right to work on any particular bit of floor space at any time.

Other time critical areas are live sites that need additional cabling but where the costs and implications of downtime are horrendous, such as a trading floor or call centre. Such a facility may want to have all its cabling upgraded or extended in one overnight operation.

Busy city centre facilities will also suffer from a lack of parking and loading bays, on-site storage restrictions and security worries associated with cable installers needing weeks of access time to the site.

Preconnectorised cabling should reduce time needed on site by around 75% compared to traditional installation.

Quality of the terminations should also be improved by allowing sophisticated Category 6 copper and optical fibre terminations to be made in a clean factory environment by skilled people. Each cable assembly can be 100% checked in the factory and whatever is sent to site is known to be of the highest quality.

Disadvantages

So what are the downsides?

Costs. The product cost will go up but the labour time on site will go proportionately down. To the end user there shouldn’t really be any additional costs as the overall amount of materials and labour required is going to be roughly the same however the installation is effected.

Accurate surveys. It is no good turning up with cable assemblies that are too short or so excessively long there is no containment space to store the excess cables. Accurate site surveys are therefore essential. If cables are supplied that are only terminated on one end this can make it easier in terms of quantity and quality of survey work required.

Quality

The quality of the installed product should be superior to traditional, site-terminated cabling but the end user must insist on 100% testing of the cable assemblies at the point of manufacture and visibility of those test results.

After installation some sample testing should be done on site to demonstrate that everything is going to plan. 100% testing after installation rather negates the concept of factory termination but a sampling plan, typically 5-10%, should be implemented with an escalation and rectification plan agreed with the installer if more than a trivial number of failures are observed.

One should also consider who is going to be doing the termination. It can be either an installer or the original cabling manufacturer or even a specialist third party. The end-user should satisfy themselves that whoever is doing it does has the right equipment and workforce to do this task. One must also ensure that if it is not the cable manufacturer or supplier doing the work then that same cable manufacturer is still going to endorse and guarantee the final product. Not all cables are suitable for a robust assembly process and some manufacturers will not honour their decades-long warranty if cables have been mechanically bundled without their knowledge and backing.

A final point to consider is the problem of alien crosstalk when forcing cables to lay parallel for up to 90 metres. The advent of ten gigabit Ethernet (10GBASE-T) and its associated Category 6 (Cat6A) cabling would seem to be the worst possible scenario for unscreened Cat6A cables with their inherent Alien Crosstalk and interference problems. It would appear that only screened cable assemblies will suffice for 10GBASE-T/Cat6A applications in the preterminated approach.

Conclusions

Preconnectorised cabling offers many advantages to the end user in terms of time on site and final product quality. The end-user and specifier must however pay great attention to understanding exactly what technology it is they are buying, who is doing the vital connectorisation work and what final sample testing and escalation procedures are in place after the installation work.
The preconnectorised approach can be used with either copper of optical fibre cabling and even 10GBASE-T/Cat6A applications can be accommodated when screened cabling is used.

A preterminated soluition from Connectix Cabling Systems, called Connectix Express, has just been installed by Nortech Network Services in a 48,000-port data centre project for a major power company.

The pre-terminated cabling approach has proven popular with major computer room and data centre projects mainly because of the lower time spent on site. This project demonstrated a huge reduction in on-site labour and was installed within 30 days.
In response to customer demand Connectix has introduced an on-site audit and survey service to assist the installers, Connectix will visit the site, measure the lengths required, agree a Bill of Quantity and planning schedule. This takes away all technical and liability issues from the end user and guarantees a ready-to-use product set, with minimal installation time on site.

This service has already proven a major success for a prestigious customer in the Bishopsgate financial district of London.