I wanted to share this ControlGlobal.com article, Simplicity = Freedom: Reducing Wiring Doesn't Just Save Labor, Time and Expenses.
The article highlights the DeltaV CHARMs installation at Southern States Chemical's sulfuric acid plant in Wilmington, N.C. USA. and the savings they achieved:
In the end, [Bryan] Beyer says his company saved about 50% on wiring and labor thanks to CHARMs and Emerson's other equipment. For example, instead of having to bring I/O signals 200 feet back to its control room, many could simply be tied into the existing Ethernet backbone in just a couple of hours. "We were even able to secure some digital inputs, install a horn in the control room and have a plant evacuation system for just $2,000," added Beyer.