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Most of the in-plant medium-voltage generators are grounded through resistors ranging from 200 to 400 A. In some unusual situations, the resistors may even be as high as 1200 A. Low-resistance grounding is a preferred choice for a medium-voltage power distribution system. However, extensive generator stator ground fault damages had been reported due to the prolonging generator neutral ground current, which would continue to flow even after the main and field breaker opened. This ground fault current could continue to flow for as long as 5 s depending on the generator open-circuit time constant T'do. As a result, the higher the generator neutral current, would lead to the higher stator ground fault damages. An IEEE Working Group has recently completed its study and made recommendations for medium-voltage generator grounding in a multiple source industrial environment. Based on the considerations of transient over voltage, ground fault damages, and ground fault protection, the working group suggests a few variations of grounding systems, which basically are low-resistance grounding systems during normal operating conditions, and the generator would be switched to a high-resistance grounded system from a normal low-resistance grounded system when a ground fault occurs in the generator stator. The purposes of this paper are: 1) to examine the generator transient over-voltage and currents under the low-resistance ground fault conditions, and also to evaluate their corresponding stator ground fault damages, and 2) to establish an acceptable maximum system ground fault level. [ABSTRACT FROM AUTHOR]