Utility Neutral/neutral Current Question
this topic came up on another thread but its buried pretty deep. it is my understanding from several experienced posters that under normal circumstances all neutral current should flow back to the utility neutral, not the grounded plumbing or rods.
i am trying to figure out why. bear with this simplistic example. 100a service - 3 wires in - A (hot+), B (hot-) and N (neutral). circuit 1 on A is using 12 amps circuit 2 on B is using 7 amps so a total of 5 neutral current amps have to go somewhere. they could all flow back on N, but if bonded to N at the panel is a low resistence connection to say, copper water pipes, wouldnt some of the current flow there? is the utility neutral supposed to be so low resistence that none of the current would flow to the grounds? if that is the case i need to call my utility ASAP because a considerable amount of current flows to my main ground. where i am struggling is i dont see how a utility pole or transformer would be any lower resistance than miles of metal plumbing and since they are bonded together, the current can choose (i know wrong word but im not an electrican or an engineer) either path Similar Tutorials
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Thanks!
Hello All,
Hopefully I am posting this in the correct forum! I am new to the forum and I have a question I would like to pose. I am trying to make an extension cable for my telescope hand control. I have had good results with the 25' length but it is to short . So I made another one 50' in length but it give me connection error codes. The cable is correct as it worked for a while .I am using an rj12 6pin connector with cat5 cable(24awg). The power supply is 12V DC with 2.5 amps running on house AC. The question is: If I put a different power supply on that is 12v DC using 5.0 amps will the increase in amperage effect the DC current flow? Thanks, Don
I have an outdoor light fixture that I am trying to replace. The house was built ten years ago.
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I have an older QO-Square D eight circuit panel. It is being used as a subpanel and when installed was not bonded.
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Hi all, this is my first post, so...my kitchen was just renovated and the electrical outlets are on the walls and I wanted them in plugmold under the cabinet. Why didn't it happen? Long story, but I'm doing it myself now. The electrical receptacles are on 2 separate circuits with a gfci receptacle on each and neither circuit has a receptacle outside the kitchen where I can put the gfci's, so I'm putting gfci breakers in the panel instead. I've run into a different problem on each circuit that'd like some advice on.
Circuit 1: this is a 20 amp circuit. I have to plug this circuit's neutral wire into the gfci breaker, but I couldn't see which neutral wire matched the hot wire (buried in mess of wires) and I don't have a continuity tester so I just pulled one neutral at a time (tedious) until the circuit failed, but it never failed. So I did this again for every neutral...same result. This circuit shares a few boxes with other circuits so I'm wondering if the neutrals on different circuits are tied together somewhere, and if so I'm pretty sure, but not completely, that that's not going to work with the gfci breaker. So I didn't install that gfci breaker since I'm not confident it would actually gfci (yep i verbified gfci). What do you think? Circuit 2: this is a 20 amp circuit. This circuit currently has the refrigerator, gas stove and range hood, and then a gfci in front of 3 electrical receptacles, which already sounds bad since I thought the kitchen receptacles required 2 dedicated circuits. I replaced that breaker with no problem, but it tripped after a few minutes and continued to trip every few minutes. I haven't changed anything else on that circuit yet and it's never tripped before, but now it is, so I put the old breaker back for now. The current gfci receptacle is only protecting the 3 outlets since the appliances are ahead of it. I know you wouldn't normally want the appliances gfci protected, so do you think the refrigerator motor may be a problem? Do I need the appliances on a separate circuit? What would you suggest I do? Thanks, and if you're wondering "why all the effort?", it's partly because I'm meddlesome, partly because I'm bored, and partly because the backsplash tile is to be on showcase, not the electrical receptacles.
Hi guys. I'm Dan, and I'm in Knoxville, TN. I know running power to a shed is a very common topic here. I've been doing tons of reading and feel pretty comfortable with the requirements, but I have two questions I haven't been able to find a clear answer to.
First, my situation: I'm having a 10x16 shed built in my backyard, to be used primarily as a woodshop. I need more than a single circuit, so I know I need a subpanel and two grounding rods at least 6' apart, bonded to the subpanel with #6 bare copper wire. My house has 200 amp service, and the main panel is in the garage at the opposite corner of the house from where the shed will go, so it would be pretty inconvenient to run a feeder from, there. But there's an existing 100 amp subpanel in the basement, presumably installed when the previous owner finished the basement. I'll be running a 60 amp feeder from that subpanel to the shed. My total run will be something like 75', so I'm running #6 THWN for the two hots and neutral, and #10 THWN for the ground. I plan to bury it in 1.25" schedule 40 PVC, buried 18" deep. My first question relates to how I need to run the wire when it's not underground. The basement is finished with a drop ceiling, so I plan to run the feeder across the drop ceiling, out of the house, down to the ground (it's a walk-out basement), then underground the 26' to the shed. I assume it still needs to be in conduit for at least the part that runs up the wall of the house. But what about inside, when it runs through the drop ceiling to the panel? Does it need to be in conduit for the whole run? Or would I just staple the four wires to the joists or something? The other question relates to the trench. I've got a rain gutter downspout that discharges right at where the shed will soon be, so I'm running a 40' length of 4" PVC to pipe that water past the shed. It will be buried just about 6-12", just enough to run under the shed. Can I run the power conduit in the same trench (obviously, deeper)? Presumably I'd dig the 18" trench to the shed, lay the schedule 40, then add a few inches of dirt to bring it up to about 12" deep, and extend the trench past the shed at that depth, then lay the 4" drain pipe and backfill. Or do I need to dig two separate trenches? Is there a rule about how far apart they need to be if so? If anyone sees any other flaws or concerns with my plan, please do speak up, I want to do this right. Thanks! Dan
So Nap does the NEC allow any type of reduced neutral for residential or is it always a full size neutral.
That is one thing i like about this site, you get to learn how things are done south of the border, in your case north of the border.
Hello,
I currently have one light switch which operates an outlet in one of my bedrooms. I want to add a ceiling fan that has independent switches for the fan and light - but I want to make sure i'm wiring it correctly and safely. Current (First Pic)- Live hot feeds into bottom of switch (bottom insert hole) and the all of the bedroom outlets (pig-tailed) tie into the bottom of the switch on the screw. Coming out of the top of the switch is one hot which feeds to a single outlet. All of the neutral and grounds are tied together. New Plan (Second Pic)- Remove the constant outlet hot from the screw, add a new hot wire to the top of new switch and run a wire up to the attic for fan. Add another hot wire from the bottom of that switch to the third switch and run another wire up to the attic for the lights. Re-connect the constant outlet wire to the screw of the last switch. Connect all the neutrals and all of the grounds together. At the top of the ceiling, connect the neutrals and grounds together with the fans neutral and ground. Connect the fan hot to the fan switch hot, and the fan light hot to the light switch hot. |