I thought that but didn’t want to guess. But aren’t we discussing GFCI protection for ungrounded receptacles?
yes, but Michael mentioned how they aren’t meant to protect equipment as part of his comment. That’s why I said people sometimes think everything will be protected. Didn’t mean to throw anybody off, it was still early and not enough coffee yet.
me too!
I can relate to that. 
If you’ve got time you, well everyone really, should watch Mike Holt’s grounding versus bonding webinar. It covers just about everything you could want to know, at least from our perspective. I suppose on the engineering side people would want more.
Good point. Mike does provide a great deal of free stuff. You can find it here:
Hello Juan. I wanted to point out a couple of things. First, an electrical system can function without practically any of the components designed for the protection of both personnel and equipment. However, it is not a proper installation. You can actually connect conductors directly to a source without any type of overcurrent protection and the loads will function fine. Only when a problem or failure occurs does the need for either overcurrent protection or an EGC arise. Same holds true of GFCIs, AFCIs, or GFPEs.
Second, the EGC’s should be at the same potential as the ground. If not, there exists what is termed as a “potential difference” and that can create a shock or electrocution hazard.
Confusion is created by discussing grounding in terms of many purposes. For example, a wall receptacle equipment ground is mostly for human safety. Code is only concerned with human safety. And does not care about equipment (ie transistor) safety.
Human safety is about a ground centered in the main breaker box. Three prong receptacles, water pipe, and earth ground all connect to that ‘safety ground’ bus bar so that human life is protected.
GFCI (with or without a ground) is also about human safety. And also defined in the code.
Transients (ie lightning) is a completely different topic. Code discusses transient protection only in terms of protecting human life. For effective lightning protection, a completely different ground applies - single point earth ground.
Notice that human safety and transistor safety share common wires and electrodes. But details make all that different.
For example, connect a 200 watt radio transmitter to a long wire antenna. Touch the wire and feel zero volts. Touch another part to be shocked by maybe over 100 volts. How can two completely different voltages exist on a same wire?
When discussing human safety, voltages vary little on a wire. When discussing transistor safety, wire becomes an electronic component; voltages can vary significantly.
When discussing safety grounds, wire resistance is the relevant parameter. When discussing the same wire for transistor safety, impedance is relevant. Resistance is mostly defined by wire thickness. Impedance is mostly defined by wire length.
Above are examples of why code requirements different from transient protection. Code only defines minimal grounding. Transistor safety is about upgrading an earthing ground system to exceed code requirements.
Wall receptacle safety ground is irrelevant to transistor safety. Since the long wire with many bends and splices can be a low resistance connection AND a high impedance connection. Good for human safety. Bad for transistor safety.
Thank you Will.