Ground Fault Circuit Interrupters Part 1

Hey everybody, my name is George. I’m with Argo electrical services and I am the surge protector guy. So we are all the way up to podcast number 14. This podcast is about ground fault circuit interrupters. So if we dig into our National Electrical Code Book, section, two 10.8 Chapter Two tn dot a ground fault circuit interrupter protection for personnel. All right, a listed class a GFCI shall be provided in accordance with two 10.8 A through F. The GFCI shall be installed in a readily accessible location. That means where personnel can utilize it. Okay. So the next thing they have is an informational note, says C two 15.9 for GFCI protection GFCI protection for feeders. And so I flipped over there and I open that bad boy up. And let’s see here. Well, nope. I’m in the wrong spot. All right. Two 15.9. So if we read that, it says feeder shall be permitted to be protected by listed ground fault circuit interrupter installed and readily accessible location in lieu of the provisions for such interrupters specified in to 10.8. Ground Fault Circuit Interrupter protection of the feeder circuit protects all branch circuits supplied by that feeder. This type of GFCI installation is permitted in lieu of branch circuit requirements of two to 10.8 GFCI protection in the feeder can also be used protect construction site receptacles as covered in five 90.6 A provided the fader supplies no lightning branch circuits, although it may be economical, more economical and convenient to install GFCIs for feeders, consideration should be given to the possibility that a GFI might be monitoring several branch circuits and will de energize all the branch circuits in response to line ground fault from one branch circuit. So all right, I know you’re saying what the heck does that do for me? Well, the big thing about it is I believe what we need to what we need to see in that whole discussion is you know that we’re going to put a GFCI device or you know, protected line, basically where it’s being used. So, if, if you’ve got a feeder, running out to a cell panel is GFCI protected, and that thing trips, it’s going to kill everything. So I got to dig in through the code book and it’s just like, you know, your voltages coming down to power lines, power lines running into the meter base at your home. These circuits are not ground fault circuit protected. Okay. And so there you go. Anywho so let’s see here Hmm, I have gotten completely out of whack, all right. So anyway, for purposes of this section, the distance from receptacle shall be measured as the shortest path. This power supply cord connected to the receptacle would follow without piercing a floor, wall ceiling or fixed barrier. And what that means is if I’m using a skill saw off the deck of my home, that receptacle needs to be ground fault circuit interrupter protected if you know if we’re using a blender in our kitchen countertop GFCI protected so here’s a little bit more food for thought. The consumer production Safety Commission has reported a decrease in the number of electro cue shins in the United States since the introduction of ground fault circuit interrupter devices in the 1971 National Electric Code. Real quick definition electrocution, that means someone gets shocked and they die. If you got shocked and you did not die, you have not been electrocuted, you are merely shocked. Okay. Most safety experts agree that GFCIs are responsible for saving numerous lives and pretend preventing countless injuries. When the lack of conductors are passed through a sensor, and are connected to a short trip device, as long as the current in the conductors is equal, the device remains in a closed position. If one of the conductors comes in contact with the ground and object, either directly or through a person’s body, some of the current returns by the alternative path resulting in an unbalanced current, the Teredo coal sees the unbalanced current and the shut shut tree up mechanism reacts to the Open to open the circuit, the circuit design requires does not require the presence of equipment of an equipment grounding conductor, which is the reason four Oh 6.4, D to C permits the use of GFCI as replacements for receptacles and grounding mains that do not exist. So real quick, let’s go back to the shunt trip device wires a common place, that there are always shunt trips installed, that you probably really didn’t know, gas stations. That means if there’s an issue, it’s going to trip the power to the entire main, it’s gonna kill the power and then we don’t have any explosions, like we see on the movies. Okay, now, this section right here, which I’m going to talk about. And another thing is is for US Code chapter or section four, oh, 6.4, D to see, for me, it’s the use of GFCIs as replacements for receptacle, where a grounding means does not exist. Okay. Now, what this is talking about, so I’m an electrical contractor in the Northeast Georgia area, about 4550 miles north of Atlanta, there are a lot of homes around where I live, that were built in the 50s and 60s, okay. And a lot of a lot of these homes were built with the old cloth wiring, they only had a hot and neutral wire in there no ground wires. Well, these inspectors when these people sell their homes, people come in and they want an inspection report. Well, none of the receptacles on the property are grounded, the guy tries to stick his little plug in. And if they’ve got, the old receptacles suddenly has two holes, which is what it should have. You know, he’s like, Well, the, none of the circuits are grounded. And that is true, but it’s not 100% True. But in any event, the code allows us to either install a GFCI reset receptacle or nail a GFCI breaker. Okay, so in this part of the codebook, I purchased a handbook section or whatever, which, you know, this gives me the same thing that your instructors have for the most part. And there’s a picture in there and it’s got, you know, the source, you know, line in neutral and it’s got the circuit breaker feeding your shot tree up, feeding a solid state circuitry or whatever. And that’s the hook up that uses that. I guess it’s a lead ring or whatever I’ve I’ve seen them before I’ve installed them before, I don’t want 1,000% understand how these CTS work exactly. It’s like a CT. And by that I mean a socket transformer. But anyway, it it’s a hoop, that the wires run through the circuits run through, they’re not covered by metal pipe or anything like that, and that who monitors the system, and if it gets out of whack, it’s going to cause that shunt trip to open. And when that shunt trip opens, then whatever that circuit is feeding, whether it be the whole property, whether it be a dedicated circuit or whatever, then you know, it kills the power to it now coming out of that. It also goes up to a push to test button and that runs through a resistor which goes back to the other side of the neutral wire which is not run through that ring Okay, and then on the outside of that, he shows the load, you know, basically a receptacle or whatever, it’s kind of a fancy deal.
I’m sure this is more for an industrial setup, it is a residential, but he still kind of gives us an idea how ground fault circuit interrupter breaker or receptacle works. Obviously, the shunt trip part is built in to the receptacle or the breaker, and there’s a push to task deal in there with a resistor. And if that resistor burns up, bam, it’s no good anymore. The GFCI is today and the GFCI breakers, they are not supposed to allow power out if it’s faulty. That means if that resistor burns up, the switch inside cannot burn closed. Back in the day, I remember GFCI receptacles in kitchens, and I’m remember, especially a church I used to go to and where everybody made culture, whatever there’s GFCI receptacle up there and you could go up there and you could push that test button and it would not work. But that circuit was hotter than pistol peak. And I’m no longer will that happen. And it’s another you know, just like we talked about in 1971 when they you know this is saving lives some of the old time electricians complain and bitch and moan about it. But anyway, a variety of GFCIs are available including portable and plug in types and circuit breaker type types built into plug caps and receptacle types. Each type has a test switch so that units can be checked periodically to ensure proper operation manufacture the manufacturer’s installation and use instructions specified monthly testing to facilitate this important ongoing safety check GFCI was installed to protect receptacles covered in two 10.8 A and B are required to be readily accessible GFCI is operate on fault currents of four to six milli amperes. At trip levels of five milliamp hours, the instantaneous current could be much higher, the shock can be fifth can be failed during the fault. The shock can lead to an involuntary reaction that can cause a secondary accident, such as a fall GFCI do not protect persons from shock hazards. Where contact is made with the ungrounded hot and grounded neutral conductors are between different ungrounded hot conductors. And, you know to the best of my knowledge, the ground fault circuit interrupters can tell the difference in in the load on the neutral side. It detects moisture and that’s what makes it trip arc fault breakers and receptacles. Now they they monitor the unbalanced load on that neutral to the best of my understanding. This is George with Argo electrical services. I am the surge protector guy you can find me at Argo You can just Google at Argo electrical. You can email me at info at Argo Or you can call me 770-596-1437 Thanks for stopping by. I look forward to talking to you soon.

Tags: , , ,
Previous Post

Ground Fault Circuit Interrupters Part 2

Next Post

Grounding and Bonding Part 2

Call Now ButtonTap Here To Call Us NOW!