Originally posted by: westonpa
In my experience of using the Phoenix Interbus and Profibus the 'techs' prefer what they know because for them that is easier to 'fix'. If a customer asks their techs for their opinion the 'negative' one tends to win out. In my days as an automation comissioning engineer I used to find that the maintenance guys/gals were in fear of fieldbus because for them it was like 'Black Box' tecnology and of course they were not working on it for long enough periods to build up sufficient 'fault finding' experience. The system can run ok for long periods and then when it goes down they get in a pickle because they cannot remember what to do. For us commisioning guys/gals it was not an issue because we worked on it everytime we commissioned a new system and so fault finding was relatively easy. This can be more important of course when certain field bus faults effect large parts of the automated system and thus increase the pressure for a quick resolution.
This is probably the real reason rather than one of reliability. Its been a while since I've done any fault finding so I don't know what tools are available but I would have thought that there must be some simple to use hand held analysers to make fault finding easier. It can't be much more difficult than fault finding an analogue loop can it?