It is difficult to calculate bandwith for a camera, it depends on the complexity of the image. the quality of the image, the motion in the image, the speed of the motion in the image, the colors in the image, the compression used.........
guess at mbps
x2 DS-2CD2722FWD-I Frame rate: 25 Frame Size: 1920 x 1080 - 15
x3 DS-2CD2142FWD-IWS Frame rate: 20 Frame Size: 2688 x 1520 - 33
x2 DS-2CD2385FWD-I Frame rate: 20 Frame Size: 3840 x 2160 - 40
You may be over the top if you have a lot of motion. Cut your frame rate and Iframe to 15 on all cameras. On non critial cameras reduce the quality. Then test again, with motion.
Advanced Video Bandwidth and Storage Calculator, intelligently calculates video surveillance parameters NVR and VMS, h.264 & h.265
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