I am trying to get my head around the P82b715TD I2c Bus extender. according to the diagram at your webpage, the TX device is connected to the CPU (A raspberry pi with an NCD adapter)… I have 2 devices on the bus. A relay module at 0x20 close to the RPi and a SHT25 at 0x40 that I wish to put out remotely. I have 20’ of #18 wire. and I power the TX and RX with 13v … what I notice is that if I plug the RPi to the TX, I lose the bus. nothing shows with i2cdetect but if I plug in the RPI to the RX it works – the problem is if I want to plug the SHT25 on the other side, the TX, it does not get +5v to power the unit…
so the question is - how exactly do you expect these to work? Do i need to rewire the modules to provide +5 to the remote bus?