Control.com - Nerds in Control

how do we investigate and develop work process or tools to assess quality and life expectancy of existing field. Is there a tool to check the quality of existing wires?

hello,
try Instrumentation Design Office it have lots of management tools and wiring templates for standard drawing of instrumentation design (try googling i forgot the websites)

There is indeed a tool to help assess the quality of field wiring, at least its insulation. It is called a megohmmeter.

Whether the effort to check every conductor is worth the results is another matter.

My tool of choice is a megohmeter, or megger (or is it meggar? I get so confused!), used to check the integrity of the insulation of each individual wire. Of course this has to be done when the process/control system is not in service, and it does take a lot of time.

It doesn't really give a good indication of life expectancy, but periodic measurements will produce a trend.

A Megger will check the insulation but you would need to disconnect all the field devices first because they could be damaged by the high voltage from the Megger.
You might be better off doing just a visual inspection, look for things like cracked brittle insulation, damaged sheath cable pulled out of glands etc.
Another test you can do is disconnect the main ground and with an Ohmmeter make sure none of the cable shields are connected to ground anywhere which will cause a ground loop.
Roy