It has to do with distance,
in general
One to one can travel 1,200 meters,
A pair of two can travel 6-700 meters,
A pair of fives can travel 2-300 meters
More than ten distances of 5-70 meters can work stably
When a 485 interface is in a close distance, there are 32 can be hung, there are 125, and there are 255
See what manufacturer's 485 interface chip is used and the model.
Generally, less than 32, and 485 Repeaters are added
It has to do with distance, and in general: One to one can transmit 1200 meters, a pair of two can transmit 6-700 meters, a pair of five can transmit 2-300 meters and more than ten distances in 5-70 meters can work stably a 485 interface at close range, there can be 32 sets of hanging, there are 125 sets of hanging, there are 255 sets of hanging to see what manufacturer's 485 interface chip and model is used. Generally, less than 32, and 485 Repeaters are added