A few years back I had issues at a site with their cabling. It wasn't a CCTV site but the same issues apply. A lot of the problem was to do with using crimps instead of jacks/patch panels. A lot of suppliers aren't aware of the different crimps required for solid condutor cable (ie normal building cabling) compared to stranded conductor cable (ie patch leads).
Personally I would only ever use jacks/patchleads at both ends.
below is out of a document I sent the customer....
Network Cabling: All network cabling should be terminated correctly to specifications (depending on the spec of the network) ie CAT5, CAT5e or CAT6 typically. To future proof an installation for more than just a few years nothing should be installed to less than CAT5e (preferably CAT6) to get the longest life out of the cabling with advances in technology.
Cabling should be terminated on the wall socket then run back to the Patch Cabinet maintaining the correct specifications for bends, ties, pathways with regards to proximity to power cabling etc. At the Patch Cabinet the cabling should be terminated on the relevant specified Category of Patch Panel (CAT5e or CAT6 typically numbering in 16, 24 or 32 sockets combinations in larger installations and down to 4 way faceplates for smaller or domestic installations). This cabling may also be known as the “fixed cabling” as it should now not be touched by the end user. The Wall Socket is then numbered/labelled to match the corresponding socket of the patch panel.
At each socket, Patch Leads (aka flyleads) are used to connect the Wall socket to the network card in the Computer and at the Patch Cabinet a Patch Lead is used to connect the point of the patch panel to a port of the Network Switch.
“Fixed cabling” contains 4 twisted pairs of solid copper cable and although it can be bent it is not meant to be flexible on an ongoing basis. Patch leads however contain 4 twisted pairs of stranded copper cable and are made to be flexible and their crimped ends normally have a moulded “boot” over the cable entering the clear plastic of the crimped end to help secure the crimped cables
The fixed cabling being behind the patch panel and wall socket is then safe from being flexed and/or damaged and should not require any attention. Patch Leads on the other hand are accessible by the end user and as a result may be plugged in /out many times with no detrimental effect (provided the network is switched off at the time). Should they become damaged or “suspect” it is a simple end user procedure to simply get another one (Officeworks, Harvey Norman Dick Smiths etc) and plug it in.
This is how a network should be configured:
Computer/Device--Patch Lead--Wall Socket--Fixed cabling--Patch Cabinet/Patch Panel--Patch Lead--Network Switch
In House Cabling:
Your fixed wiring network (ie the cabling within the walls) has been incorrectly configured:
Computer--Patch Lead--Wall Socket--Fixed cabling/incorrect crimps--Network Switch
The network cabling has been configured incorrectly by having no Patch Panel. Instead the fixed cabling is coming straight out of the wall/ceiling and has then been crimped with RJ45 connectors on the ends of the cable which are then plugged directly into the Network Switch. The crimps on some cables haven’t even clamped the outer blue sheath. Also the cables have not been labelled very well. They are labelled in the cabinet with names that aren’t immediately recognised as to where they are with no plan as to what the room name refers to and at the wall socket end no labelling whatsoever as to whether the point is for data or phone or what number it is.
This immediately creates 2 problems:
- Cables are not easily identified making trouble shooting of a network issue quite time consuming.
- If a cable becomes “damaged” or “suspect” the computer on the other end cannot connect to the network until a “cabler” or suitably skilled person comes to the site to recrimp the cable. Whereas a patchlead can be purchased over the counter at various retailers and changed by you the user.
The likelihood of a cable becoming damaged is quite high due to the fact that crimping a solid conductor cable should not be done where the cable is likely to be plugged in/out a number of times, due to the fact the solid conductor cables tend, eventually to have a bad connection at the crimp.
This bad connection problem has been greatly increased due to the fact that the wrong crimps were also used. As can be seen in the photo below the left the Stranded Conductor Crimp has 2 points that pierce the stranded cable to make a good connection whereas the Solid Crimp has 3 prongs which connect by using the IDC (insulation displacement connector) method ie the solid conductor becomes wedged between the prongs. What has been used at the Resource Centre is the Stranded Conductor Crimps which when crimped on a Solid Conductor will make a connection for a period of time but will eventually fail, especially when physically handled when looking for a particular cable or simply when unplugged and plugged into the network switch.