In some elevator installations, network video over the traveling cable is stable at the beginning, but gradually becomes unstable — freezing or dropping after months or years of operation.One common reason is that the flexible Ethernet inside traveling cables has a shorter effective distance than standard solid cable, often around 70–80m. Continuous bending over time can loosen twisted pairs, increase crosstalk, and degrade signal integrity.
In mid- to high-rise elevators, traveling cable lengths often exceed this range. When instability appears, many projects restore stable communication by introducing 2-wire Ethernet Extender — using one twisted pair, or switching to existing 2-wire inside the traveling cable.
Here is a brief application:
