Control.com - Nerds in Control

Hello everybody,

As a customer for the control system for thermal power plant DCS, we defined certain features for Wiring Scheme for inputs to control system. There I found one line written as:

"All analog/binary inputs and outputs shall be capable of withstanding 500V DC common mode and 500 V AC peak to peak between analog and digital parts. All analog outputs shall be short circuit proof."

I want to know what is the exact meaning of this line. What are the technical aspects behind it? Furthermore, if I don't include this line in my specification, then what will be the implications of this on my control system in view of safety, accuracy, system speed and some other if any?

Second, I will be very thankful if somebody can give me materials regarding this.

Third, what are the standards available that defines this condition? What are the tests defined for this parameter to access?

Fourth, if it is a necessary parameter to define for control systems, then what should be the typical values for this? How to arrive on a correct value required for my conditions?

I want this information as soon as possible as I have to release this specification soon.

Regards,
Bhupesh Gupta