Wiring RS-485

Hi,
I’m tried to planning wiring RS485 device network in my house. I have done data cables distribution, but It is like star typologies, but I need to use RS485. I attached schematic wiring. I don’t know how to connect among devices. I suppose that, it not possible to get 5V than I use 12V and on I convert to 5V by the help LM7805. I use device 3rd product like digital 3 phase electrometer location in main power switch board. Every cables has twisted pair and shielding.

RS485_situation.fzz (11.5 KB)

Just connect all A pins together and all B pins together. You've done it with two of them, just do the same with the others.

Technically you shouldn't have a star network with RS-485, but if the speed is slow enough I think it's OK.

You are also supposed to terminate each end with a 120R resistor, in a star there are many ends so I don't know what you should do, I'd probably at least add one to the "master" transceiver (is that what is shown on the drawing?).

Not sure what you mean by the 5v/12v part.

You also have to wire up the TE and RE pins according to how you intend to drive this lot, typically they are connected together on each transceiver and controlled by the local CPU.


Rob