What is the power of the camera used for monitoring?
If all of the moving point, then the power supply per set of AC24V / 2A, each 50W, 31 * 50 = 1550W, that RVV2 * 0.75 power cord is not enough.
31 cameras, if all fixed, then the power supply of each camera should be DC12V / 1A, each 12W, 31 * 12 = 372W, RVV2 * 0.75 power line is enough.
You look at your project inside the 31 points of the specific circumstances, calculate the power consumption, you can cloth a few RVV2 * 0.75 trunk power out.
