Looking at the IE calculation there is a variable for grounding depending on what type system you have installed, and noticed that the grounding type can have a significant effect on the calculated IE energy on ungrounded vs grounded systems. Just curious if anyone can shed some light or point me in the direction of some literature that would better explain the cause of increased IE on ungrounded systems. I see the variable change in the calculations and there is a brief statement about this and found some articles that discuss the grounding types etc. but could not find any technical literature on the “why’s” any information is greatly appreciated. Thanks… READ MORE.
The NEC contains specific articles that dictate when you shall ground, when you shall not ground, and when you are permitted – but not required – to ground. These code requirements are based on various factors such as whether or not there are connected phase to neutral loads, whether only qualified persons service the installation, and operating voltage levels.
Jim Phillips, P.E. – April 2005 – NECDigest
Download Article: Grounding Power