It might. And you may may get away with it. However it is strongly recommended to not do it. Reasons:
(1) Firstly the max allowed category 5/5e/6/etc cable length is 100m including patch chords. Any joins (splices) like patch chord to wall outlet, Imperfect terminations creates impendence issues and slightly reduces the maximum usable length and generally 95m is considered safe.
(2) Installers maybe tempted to skimp on effort by trying not just 110m but even 120-140m. Many come from analog CCTV camera installation background, where extra length causes deterioration in video quality (few frames or part of frame), which may not be noticeable or bothersome to human eye. And they may not hesitate to extend logic to Digital IP cameras as long as "it works".
(3) Longer cables cause transmission errors at ethernet level and cause IP cameras to occasionally go up and down depending on what frame is lost/corrupted. It will manifest in frequent "NO-LINK" or "OFFLINE" messages on NVR screen OR few ping failures or longer ping response times with larger packets (say 40-65K) and so on. It will just result in camera instability at some point.
Therefore we recommend to stick to 95m max. If their is a need to run longer runs, we can use a PoE Extender (instead of new switch in between which will have complexity of introducing UPS power supply) like illustrated below:
Try to connect to PoE+ port if available and use PoE+ extender. The extender is like an ethernet repeater which tunnels Power too. A part of power is consumed by the active extender (1-2 W) and more power than usual will be taken by resistance of extra cable lengths and we need to sure that their is enough power available at the camera. With the above method, 200m cable lengths can be supported for IP cameras (we have used around 160m reliably on one outdoor IP camera).
Their is another interesting application of the above solution as it can extend both Power & Ethernet and that is to extend ethernet only. Suppose you have a backbone cable (switch-switch) length of more than 100m and you want to avoid fiber. a good number (more than 2) of these can be chained. If backbone switch port is not PoE enabled a PoE+ injector can be introduced on one side to power the extenders and then run them for longer distances. This can be used to substitute Fiber in apartment CCTV setups (*fiber work is costly and it needs specialized labor) with Cat6 UTP cable. Unfortunately this is a trick we also missed.
- Suman Kumar Luthra @ APRC-P3 Telecom Sub-Committee
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