Even if it's part of specifications, for me it's totally stupid to use an interfacing technique, which generates common mode interference by design. And it heavily violates concept of saftey earth connections, because then you are not allowed to make any earth connections at recievers! That's really stupid. Why not using voltage generators (0...10V) when wanting to connect more than one reciever? This would be much easier, and no additional common mode signal is generated.

For me the only good reason to use 4...20mA technique is, that it supports two-wire transmitter technique. Means, you can route power supply and signal by the help of only two wires. XTR100 from Burr-Brown is a good example. Use it with 500R shunt resistance and without chaining, and of course, make a earth connection to signal ground.

Our products exhibit symmetrical signal routing (signal voltage of +-10V). When we use current sources we forbidd 'chaining' and recievers have shunt resistors of 500R.

Kai