Building a power cart, need some GFCI clarification

[Brucey]

If it's inside and away from moisture, I would agree.
But these portable carts can be used in many environments. And safety is always my first priority with electricity.

For max safety you'd prob want to incorporate something like this, combo afci/GFCI, covers both electric shock and electrical fires.

https://www.amazon.com/Leviton-AGTR1-W-SmartlockPro-Function-Receptacle/dp/B01CG8MTN4

 

[timselectric]

In AC power systems you get capacitive coupling between life and non current carrying parts even if they are not conductive
In this photo we have a medium voltage cable Lets pretend for a second that we peel back just enough of the outer layers of an energized cable to expose the white layer of Kynar insulation.
It is an insulator so you would expect it to be safe to touch.
Let me assure you IT IS NOT...
You could be killed...
View attachment 203983
I have on the other hand bare handed the cable as far in as the shield.
But let me tell you if you don't have that Semi layer and the copper to drain off the charge the capacitive coupling will build up enough potential its as dangerous as touching the actual conductor.

Lets have a look at another example a transformer
View attachment 203986
In this case you can capacitvely couple the primary to the secondary without a bond to drain the charge off.
Look closely at a transformer and you will notice the primary is usually wound over the secondary and the core is.
So we want to bond both the secondary to ground and the core.
Sometimes on an grounded Delta power system you can still read some voltage from the line side.
But a properly designed and bonded instillation will be relatively safe ( but with stability problems, why its no popular to wire this way anymore )

Add some actual capcitors to a system now.
As they age they build up charges inside the caps in places that will not easily drain.
In time a disconnected used Cap might bounce back as we call it, this means even if you discharged it before hand the residual charge inside can work it way to the terminals and give you a nasty surprise.
View attachment 203989
Add some high frequency electronics to the mix and it can be unpredictable how things will develop charges inside and out.

SO GFCI Good.
Bond where you can....


I assume no liability for your choices based on my little talk here.

I don't disagree with what you are saying in this post. But it's relative to the voltage at the source.
I have done a lot of medium voltage work, over the years. It's a completely different ballgame.
There's a huge difference between voltages in the 12kv to 15kv range and under 250v.
We need to keep the responses relevant to the field level that the questions are about.

 

[timselectric]

For max safety you'd prob want to incorporate something like this, combo afci/GFCI, covers both electric shock and electrical fires.

https://www.amazon.com/Leviton-AGTR1-W-SmartlockPro-Function-Receptacle/dp/B01CG8MTN4

GFCI yes.
But I would avoid the AFCI combination.
They are still very prone to nuisance trips, from normally operating appliances.

Mainly motors as previously mentioned by @740GLE

 

[DPC]

I don't disagree with what you are saying in this post.

I once saw a guy stick his meter lead into a block wall in a shower stall in a College dorm and get 250 volts to drain pipe.
Whats interesting is the building had a 208 service....
Know what caused that ?
A screw in a ballast on the other side of that wall.
A grounded case with no path to ground, a wet wall an easily reached bonded plumbing fixture....

The first code book I ever bought was the 1988 Ontario electrical code.
It was about the size of a large paper back novel
it cost 19.95 at the hydro office.

Today its twice the size and 10 times the price ( last part pissed me off the most )
The reason might be slightly easier to read larger form text but a lot of people have been hurt in the past 35 years and the rules have been tightened and changed constantly ( even though physics has not changed all that much ).
Too many accidents continue to happen.

I want to get the last word in so my answer to the question is yes it makes a difference even at low voltage.

 

[timselectric]

I once saw a guy stick his meter lead into a block wall in a shower stall in a College dorm and get 250 volts to drain pipe.
Whats interesting is the building had a 208 service....
Know what caused that ?
A screw in a ballast on the other side of that wall.
A grounded case with no path to ground, a wet wall an easily reached bonded plumbing fixture....

Proper grounding would have avoided that.
Electrical ground, not an earth connection.