you don't get shocked if you touch only the hot screw on outlet?

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LadyDi said:
Qualified electricians understand what to touch and what not to touch.

I tell my students to practice the old saying "first to make; last to break."
What I mean by this is that one never wants to be the intentional ground of a circuit. Otherwise, one risks shock or electrocution. Therefore, practice making up the neutrals first and taking them apart last. This mindful practice helps keep one safe by ensuring the neutral path is always hooked up.

So, if you touch a 120-volt hot screw with one finger (intentionally not touching any other known grounded surface), should you get shocked? The answer is no. Of course, I do not recommend the practice.
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Not trying to promote hot work, but one sometimes tailors the order of things to the needs of the application. Been times I maybe didn't connect the EGC to the yoke of a device until it is the last thing left, that way you not grabbing something grounded while working with the ungrounded conductors.
 
LadyDi said:
I tell my students to practice the old saying "first to make; last to break."
What I mean by this is that one never wants to be the intentional ground of a circuit. Otherwise, one risks shock or electrocution. Therefore, practice making up the neutrals first and taking them apart last. This mindful practice helps keep one safe by ensuring the neutral path is always hooked up.
Click to expand...
Seems to me it's the opposite. For example if I'm making up a live service drop, I would cut the messenger and tie it out of the way first, then cut the hits. To reconnect, I would do the hots first then the messenger.
 
Do you believe that you are safer working on a grounded circuit?
 
Hv&Lv said:
25 kV feels like holding a bag of bumblebees.
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And a whole floor of 277v corridor lights just tasts weird...and feels like your hand in a vice.
Just so you know... it was a floating neutral (bad make up) w/ more bad make up, the dip head had twisted one #12 ground out through the end of the wire nut. I was just pulling wires out if the box and fixed the floater through the ground and box. With my hand, not mouth. I tasted that sum bit and felt like a truck rolled over my arm. But, i did it one handed so...
Floaters are bad.
 
rambojoe said:
And a whole floor of 277v corridor lights just tasts weird...and feels like your hand in a vice.
Just so you know... it was a floating neutral (bad make up) w/ more bad make up, the dip head had twisted one #12 ground out through the end of the wire nut. I was just pulling wires out if the box and fixed the floater through the ground and box. With my hand, not mouth. I tasted that sum bit and felt like a truck rolled over my arm. But, i did it one handed so...
Floaters are bad.
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277 was my worst hit ever.
😂😂 It’s funny now but your right! Hand in a vice!

I swear I hurt for a couple of days and was scared for a year…
 
Perhaps a slightly sad amusing electric shock. We lived on a farm and now and again we had to isolate the odd cattle beast. We used a temporary electric fence for that. It kept the beasts in. Well, being the lad that I was, I had to try it. Hold it firmly and you could tolerate it. My poor dog didn't. I had rubber boots but my dog had bare feet and the wet grass.............:(

It took him quite a few hours before he forgave me.
 
Oscillating lights or anything returning three legs.. one hand sam. Best lesson i ever learned. Now that i think about it, i think i got the whole floor of hallways.. it was barely returning via t grid wire or such...
My proof that an idiot twisting wires and floating a neutral (and pushing one ground through the nut) means twisting conductors doesnt always work.
One vote for no twisting. Or wire nut adapters for drills.
 
electrofelon said:
Seems to me it's the opposite. For example if I'm making up a live service drop, I would cut the messenger and tie it out of the way first, then cut the hits. To reconnect, I would do the hots first then the messenger.
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Perhaps the notion seems odd to you but consider the following.

When a person touches a hot wire with one hand and has one foot grounded, a path for current flow is established through the body. The amount of time and current passing through the body is limited by voltage (potential difference) and the resistance of the body. Other than wearing rubber gloves or other insulating materials there's not much we can do to increase the resistance of the human body.

Therefore, to protect against electric shock, one must consider the other two variables:

1. Reduce the voltage (potential difference) as much as possible. By reducing voltage less current will flow and therefore less damage is done to the human body. Stand guard because voltage to ground is ready to push current through the body.

2. Reduce the current as much as possible. We know that the flow of current through the body is what does the damage. Indeed, experts say that less than one amp could cause the heart to fibrillate.

Connecting the neutrals first works towards both of these goals:
1. Eliminates pressure to ground (nothing to push current through the body) because two points are maintained at the same potential.
2. Builds a low opposition path for current flow. In other words, it gives a path for current flow other than through the body.

The underlying assumption of the referenced scenario is that a bonding jumper exists if working in a metal box and the equipment grounding conductor is installed.

Similarly, what happens in a motor ground fault that is not bonded or grounded to anything and a person touched the case and a grounded material? What happens in a motor ground fault when a bonding jumper connects an equipment grounding conductor? Was something done about the voltage? Was something done about the current?

It's about reducing risks.
 
LarryFine said:
But, not bare handed.
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Those gloves are part of the suits now. No insulting value at all.

We used what was called a “hot box” and no suit. That’s why the headaches were so bad after about 30 minutes steady. It was very uncomfortable.
We used leather gloves but they were more for hand protection than anything.
Still hurt.
 
LadyDi said:
Perhaps the notion seems odd to you but consider the following.

When a person touches a hot wire with one hand and has one foot grounded, a path for current flow is established through the body. The amount of time and current passing through the body is limited by voltage (potential difference) and the resistance of the body. Other than wearing rubber gloves or other insulating materials there's not much we can do to increase the resistance of the human body.

Therefore, to protect against electric shock, one must consider the other two variables:

1. Reduce the voltage (potential difference) as much as possible. By reducing voltage less current will flow and therefore less damage is done to the human body. Stand guard because voltage to ground is ready to push current through the body.

2. Reduce the current as much as possible. We know that the flow of current through the body is what does the damage. Indeed, experts say that less than one amp could cause the heart to fibrillate.

Connecting the neutrals first works towards both of these goals:
1. Eliminates pressure to ground (nothing to push current through the body) because two points are maintained at the same potential.
2. Builds a low opposition path for current flow. In other words, it gives a path for current flow other than through the body.

The underlying assumption of the referenced scenario is that a bonding jumper exists if working in a metal box and the equipment grounding conductor is installed.

Similarly, what happens in a motor ground fault that is not bonded or grounded to anything and a person touched the case and a grounded material? What happens in a motor ground fault when a bonding jumper connects an equipment grounding conductor? Was something done about the voltage? Was something done about the current?

It's about reducing risks.
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I am having trouble following your reasoning. Say we are splicing a circuit hot in a 4 square metal box. Let's say the box is bonded to an EGC and we are not making or breaking any of the bonding connections. In this case, I agree making up the neutral first is best, because if we were to make up the hot first that would energize one end of the neutral wire - assuming there are some loads connected to the circuit downstream. But by making up the hot first, all that does is make us have to make another live connection, there is no other increased risk besides that. Perhaps you can explain in more detail your comments about less voltage to ground or an alternate path besides through the body? I just am not seeing that.

In my service drop example, do you agree with cutting the neutral first, and connecting it last as being safest? Because in that case we can pull the meter and or throw the service disconnect so we can't get hit by current "returning" on the neutral through loads.
 
electrofelon said:
I don't really know what that means. Are you talking about system grounding? Are you talking about a circuit that is the de-energized with the hot conductors and neutral(if there is one) bonded together?
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The grounded conductor (neutral) is the intentional ground of the circuit (Article 100) Grounded Conductor. You (a person) never wants to be the grounded conductor. If its hooked up, you wont be the grounded conductor. The equipment grounding conductor serves another purpose as does the bonding jumper.
 
electrofelon said:
I am having trouble following your reasoning. Say we are splicing a circuit hot in a 4 square metal box. Let's say the box is bonded to an EGC and we are not making or breaking any of the bonding connections. In this case, I agree making up the neutral first is best, because if we were to make up the hot first that would energize one end of the neutral wire - assuming there are some loads connected to the circuit downstream. But by making up the hot first, all that does is make us have to make another live connection, there is no other increased risk besides that. Perhaps you can explain in more detail your comments about less voltage to ground or an alternate path besides through the body? I just am not seeing that.

In my service drop example, do you agree with cutting the neutral first, and connecting it last as being safest? Because in that case we can pull the meter and or throw the service disconnect so we can't get hit by current "returning" on the neutral through loads.
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In your service drop example, I would practice first to make; last to break. Therefore, I would cut the hot conductor first. The reason is that I never want to be the intentional ground of the circuit. Let me think of another way to explain my reasoning. I'll get back asap.
 
LadyDi said:
In your service drop example, I would practice first to make; last to break. Therefore, I would cut the hot conductor first. The reason is that I never want to be the intentional ground of the circuit. Let me think of another way to explain my reasoning. I'll get back asap.
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I'm not following the "intentional ground" concept. If you are grounded, and touch the hot conductor, you are going to get hit whether or not the neutral is connected. The connection status of the neutral will not affect anything. What it does do is provide a big grounded object right where you are working so I cut that first and tie it out of my way
 
When I was working on a center medium traffic signal "Knock Down" an OSHA inspector happened by and reported me. I was then required to work with a rubber matt ... that lasted about 6 months !
 
Hv&Lv said:
277 was my worst hit ever.
😂😂 It’s funny now but your right! Hand in a vice!

I swear I hurt for a couple of days and was scared for a year…
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When I was a teenager, maybe 14, I was working with the maintenance department at my school that summer. Was changing fluorescent light bulbs in a classroom and I think I stuck one end of the bulb into the socket and then touched the other end of the bulb while trying to get it into its socket.

All I know is I got hit hard. Lesson learned!
 
DBoone said:
When I was a teenager, maybe 14, I was working with the maintenance department at my school that summer. Was changing fluorescent light bulbs in a classroom and I think I stuck one end of the bulb into the socket and then touched the other end of the bulb while trying to get it into its socket.

All I know is I got hit hard. Lesson learned!
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Lessons learned that way are never forgotten. I learned that way to never pull a wire off a spark plug on a running engine while leaning on the car with my crotchal area in contact with the fender.
 
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