>ABSOLUTELY not. you will find in several of my posts >at one point
>If you absolutely can not get 0V and frame connected, >my first ideas would be to connect the shields to >frame again at one point.

////// But the frame could attain any type of potential \\\

>I would connect cable shield at each node to signal >ground (0V of circuit, where GND pin of 75176 >transciever is connected to). If your signal routing >is as shown in one of your former postings, forming a >ground loop is impossible.

////If I tie at each node 0v that would create Ground loops between inter nodes may be of very minimal effect I guess , and how will I protect the system from other issues EMI , EMC everything would conduct to my 0v reference and I might get a Ground *BOUNCE* . shouldnt I use the battery -ve terminal in any case to shunt the transients away (but its floating) from the shield using 0....100nf capacitor || with 1M ohm Resistance \\\.

/////Hey you both *Differ*\\\

>Nothing may be touched by human being and nothing may >be connected to bus frame .

//////But it isnt so Battery is hardly a danger only 110V DC ,If frame floats should I touch the Processor chassis to it \\\\.

Any ideas using 485 parts having very high Vcm rejection so that I leave the issue of shield and run evrything on THREE wire as shown in the LINEAR TECHNOLOGIES datasheet .

Apologies for Frying up your Brains .

Kindly/