We recently installed analog cameras in 3 elevator cars. The video quality is great when the car is not in use, but as soon as the car starts-up the video quality degrades. We are using an 18/2 shielded cable that was already in the travel cable of the elevators. We began by grounding the shield on the end of the cable at the car. I noticed that the interference was present, I then grounded the shield on the other end in the elevator equipment room, it made no difference. We are sending the analog signal through the 18/2 shielded cable using passive baluns. We then are sending the analog signal into an encoder where it is switched to IP, and connecting to our VMS.
******
*'** *** *** ***** ****** ** shafts ** *** *** ** *** travel ******. *'** *** **** **** 50+ ****** ** ****** **** **** a ***** ***** *** ****** **** but * ***'* **** ** ****'* an ****** *** **** ****.