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Author Topic: NCVT shows voltage on one of two NEMA 5-15 safety grounds  (Read 22158 times)

John Roberts {JR}

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #60 on: November 06, 2014, 09:39:41 AM »

i got an email from Mike Sokol threatening to ban me from the forum for that "smart guy" comment and thats not a gentle
In fact it is... A public rebuke, like you have escalated this to is worse, getting kicked out is even harsher.

Your comments seem tame but are inappropriate especially in light of your position regarding the subject.
Quote
education. Mike wants me to prove who i am also. if i have to then everyone else should have to. i didnt know Mike owned this forum. i think others that were putting me down should also be gently educated about that "or" we can forget about the "Joking around smart guy" comment i made and move on. i would thing ya'll had heard the "smart guy" comment by now. i have read post where Dick Rees has used cuss words toward people and belittled others. has Dick Rees ben gently educated or is it favortism ? and right now i'm not being a "wise guy" i'm very serious. maybe people are way too sensitive. if my "smart guy" comment offended anyone i appologize. personally i dont care what comments people use toward me cause i'm an adult. thank you

Back on your topic #1 it's spelled bus not buss (one of my pet peeves, buss is a brand that sells fuses). #2 No matter whether neutral is connected directly to the transformer center tap or to the panel there will be a low resistance connection between neutral and ground. #3 40V across a low resistance wire run is lots of amps and extremely unlikely without evidence of significant heating and probably worse. 

@Mike, (iron mike  ;D )  Yes I agree trying to directly measure DCR between neutral and ground while their is power flowing will be corrupted by any current flowing in neutral (or ground). Most VOM measure resistance by injecting a small current and looking for the voltage drop, so external voltage or current will corrupt the measurements.  Likewise my current measurement between ground and neutral is a meaningless measurement but would help determine if the ground lead is floating, or at least not connected to neutral.

JR

PS: I once measured around 40V between a signal ground at a FOH position (more like front of the field), and signal ground on the stage about 30 yards away. This was a makeshift performance venue and the surely DIY electrical wiring was more than suspect. IIRC we used an isolation transformer on the audio and warned the folks on stage to be cautious.

 
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Jonathan Johnson

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #61 on: November 06, 2014, 11:15:31 AM »

both are my full name and i used my middle name to keep my drunk dad from traking me down and harrassing me. this is the "only" forum that requires real names and some of dont like it becasue of bad family members. about a year ago my dad got parkinsons and no longer uses a computer. thats why it ended it my real middle name > harrell. all the other forums dont require real names. i even thought about dropping bakston completely and legally using my middle name as my last name. btw how we know that everyone here uses the real names ? no one asked to see my gov i.d..

Sorry to hear about your father. I have two uncles that suffer from Parkinson's disease.

By the way, when doubts about a person's identity come up, the moderators DO ask for proof. There is at least one person on these fora with a single-word name that doesn't sound like a real name, and they have indeed proven that it is their legal name. If Mike wanted to verify my name, I'd be happy to show him proof, or he could just go back through his records and find that I attended one of his seminars in Ridgefield, Washington a few years ago. Using real names generally helps keep the discussions civil. It also helps when we need real help from each other should we be a little shorthanded, or if we're visiting another venue and want to chat with the FOH tech; they may remember our names from the forum.

I know you've been harped on about this before, but using proper case (initial caps), punctuation, and grammar really does make a person seem more intelligent, and their writings easier to read and understand.
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Tom Bourke

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #62 on: November 06, 2014, 12:57:13 PM »

in commercial construction the neutral buss is not bonded to the panel can when a step down transformer is used. the ground buss is screwed right to the panel can. the neutral goes directly to the transformer xo terminal. a jumper wire is connected between the xo terminal and the transformer metal case. a ground wire is connected to the ground buss in the panel can and the transformers metal housing. emt is also connected between the panel can and transformer housing. it is my thinking that the coils in an energized transformer produce enough of a magnetic field to show a voltage reading on an some energized receptical circuts when a digital volt meter is connecter between the ground and neutral slots on the receptical. nothing else is plugged in to any recepticals on that circut. the voltage will not light a 12v test light and you dont feel any current when you touch the ground and neutral with your fingers. i never got a reading with my old analog pointer meters. it may also have something to do with the 9v battery in the digital meter. all i know is its weird.
What is being described sounds like a many turn to one transformer.  The primary in the step-down transformer is also the primary driving the magnetic field driving the single turn neutral-ground transformer.  At best your getting less than a volt if it was a perfect transformer. Given that this is just a wire outside the magnetic core it is not going to be a very good transformer and the output voltage is going to be even less.

Posts on Mike Holt's forums about stray voltage lead to 2 conclusions.  1 the wire is floating.  2 a high impedance VOM is not the right tool for this test.
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Steve M Smith

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #63 on: November 06, 2014, 01:27:29 PM »

Mike wanted to verify my name, I'd be happy to show him proof

A few years ago on a TV programme where the police showed videos of people driving like idiots, one of the officers said that if they stopped someone and asked for their name and the name given had first and surnames starting with the same letter, then it was very likely to be a false name.

That's both of us then!


Steve.
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Mike Sokol

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #64 on: November 06, 2014, 01:32:54 PM »

A few years ago on a TV programme where the police showed videos of people driving like idiots, one of the officers said that if they stopped someone and asked for their name and the name given had first and surnames starting with the same letter, then it was very likely to be a false name.

That's both of us then!


Steve.

Please don't make me ask for fingerprints and a DNA sample if someone has a suspicious name. I didn't sign up for that.😜

Jeff Bankston

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #65 on: November 06, 2014, 02:59:49 PM »

Jeff, actually I do "own" this forum. That is, I'm the moderator and get to decide valid topics as well as how much latitude I'm willing to give readers on personal attacks, language, etc... I'm also an adjunct professor at a university and "own" my classroom. I've kicked students out of my classroom for a bad attitude and taunting other students. In fact, that's my job. Every year I have to take an online course about protecting students from others with bad behavior as well as reporting dangerous incidents to the school.

The fact that you're now airing a personal message I sent you to the group shows me that you don't know how this works. This is a classroom. I get to set the limits. I will not allow personal attacks or accusations here. If you want to be on a forum where you can do anonymous attacks, there's plenty of them out there you can join, but you're not going to do it here. As I've said before, this a unique forum and I don't think there's another one quite like it anywhere else. That's because we have a bunch of really smart members here who are willing to teach others and offer what they know to the group. That's correct, you guys are the teachers here. I just read and learn and throw in my 2 cents (or is it pence? ;D) from time to time.   

So Jeff, if you're willing to learn, then please tone down the attacks and start asking questions. While there are certainly things we don't collectively know on this forum, we do know the laws of physics and math. If you have a hypothesis about a mysterious reading you're getting, then please present it to the group and we'll analyze the theory. But don't ask us to believe in mysterious meter readings that can't be duplicated, and don't ask us to believe every unsubstantiated theory that shows up on the Internet.

If you're good with that, then we'll try to understand how you could be getting that meter reading. If not, then please move on to another forum.
i did not attack anyone
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Jonathan Johnson

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #66 on: November 06, 2014, 03:11:36 PM »

Jeff, I owe you an apology. I should not have questioned your name openly in a public forum, I should have done that privately. But, because my mistake was public, my apology must be public, too. No excuses. I'm sorry.
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Jeff Bankston

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #67 on: November 06, 2014, 04:20:53 PM »

Jeff, I owe you an apology. I should not have questioned your name openly in a public forum, I should have done that privately. But, because my mistake was public, my apology must be public, too. No excuses. I'm sorry.
No problem Jonathan. It's cool. I'm not upset.
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Scott Holtzman

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #68 on: November 06, 2014, 11:12:48 PM »

I would like to say that this forum is one of the cleanest and best I have ever had the privilege to be a member of.  Using my real name keeps me professionally accountable for the content I post.  I try and research everything I post.  Mike is an incredibly qualified individual and the fact he gives back in such an unselfish way elevates this to a labor of love.

You mentioned foul language in the lounge.  To me that's a different place where Argo f*** yourself is a good greeting (if you have not seen the movie don't worry about it).
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Scott AKA "Skyking" Holtzman

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Mark McFarlane

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Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #69 on: November 06, 2014, 11:27:46 PM »

OP here,,,,


It's time for bed.
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Mark McFarlane

ProSoundWeb Community

Re: NCVT shows voltage on one of two NEMA 5-15 safety grounds
« Reply #69 on: November 06, 2014, 11:27:46 PM »


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