Improved Electrical Safety Through High Resistance Grounding

High resistance grounding (HRG) is a well-proven technology for improving electric reliability for many industrial and utility facilities such as used in petrochemical, automotive, and generating plants. Many such facilities require the increased reliability for production and operational reasons. This paper will discuss the improved personnel safety aspects of using HRG on low-voltage systems. In particular, this paper will discuss the following: 1) the probability of the three common faults occurring within an industrial plant, namely, three-phase, phase-to-phase, and ground faults; 2) how the probability of a ground fault can be used to improve electrical safety with HRG; 3) the impact of a ground fault on a system and the speed at which the ground fault on a solidly grounded system may propagate into a multiphase fault; 4) the risk reduction of a ground fault on an HRG system propagating into a multiphase fault; 5) the potential reduction in serious and fatal arc blast injuries through the use of an HRG system; and 6) potential single-pole breaker clearing issues when a second ground fault occurs on a second phase. This paper will include comments from recent testing, which was conducted at the KEMA Laboratories and presented in a recent IEEE Industry Applications Society Petroleum and Chemical Industry Committee paper in September 2014.