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Thread: Getting rid of our present electrical system

  1. #11
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    Quote Originally Posted by Galt View Post
    Are there still people who want to get rid of our present system with neutrals and ground currents


    If you mean having the neutral and ground isolated to the utility transformer in new installations then IMO yes.
    What is esoteric knowledge today will be common knowledge tomorrow.

  2. #12
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    I can remember 25 to 30 years ago there were engineers and electricians advocating for the elimination of 120 volt circuits on dairy farms. Then came equal potential plane. And haven't heard much about it. Seems it is back again.I can remember talking to older electricians back then and it was pretty much agreed upon that our system was safer from both a shock and lightning standpoint.

  3. #13
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    Quote Originally Posted by Galt View Post
    I can remember 25 to 30 years ago there were engineers and electricians advocating for the elimination of 120 volt circuits on dairy farms. Then came equal potential plane. And haven't heard much about it. Seems it is back again.I can remember talking to older electricians back then and it was pretty much agreed upon that our system was safer from both a shock and lightning standpoint.

    Even if they eliminate all 120 volt loads, there is still the MGN (and the TELCO shields which are ultimatly bonded to the MGN at the pole) which is generally just as much of a problem.

    Ideally given a practical approach, a Ronk blocker or having the POCO run a MV 3 wire delta up the the step down pole greatly mitigates the problem from the MGN.
    What is esoteric knowledge today will be common knowledge tomorrow.

  4. #14
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    Quote Originally Posted by Garygood View Post
    What is the reason for bonding the natural and equipment grounds


    Sent from my iPad using Tapatalk
    Please look at the grounding topic, under Grounding and Bonding Explained, its right at the top of the list
    Moderator-Washington State
    Ancora Imparo

  5. #15
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    Quote Originally Posted by Galt View Post
    I can remember 25 to 30 years ago there were engineers and electricians advocating for the elimination of 120 volt circuits on dairy farms. Then came equal potential plane. And haven't heard much about it. Seems it is back again.I can remember talking to older electricians back then and it was pretty much agreed upon that our system was safer from both a shock and lightning standpoint.
    Dairy farms, are few and far between in this area anymore. The one larger Dairy went to extremes with no neutral load. 480v lighting in all the free stall barns and small step downs for the absolutely needed 120v. Ungrounded. Milk parlor and office area are the only older areas where 120 is used.

    The other had some problems a couple years ago and when I brought missing pole grounds to the attention of the POCO, they said it would not affect the Dairy. I haven't heard of problems lately, but danged if all the missing pole grounds weren't repaired within a couple weeks.
    Tom
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  6. #16
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    Quote Originally Posted by peter d View Post
    The market has responded with an array of products to cover our different systems. In reality, it really is only the distribution equipment and our wide variety of plugs and receptacles that is complicated. Otherwise, our wiring methods are basically the same for all voltages under 600V.
    It's similar here as far as residential cabling practice goes. It was the different voltages for appliances I was commenting on.
    Si hoc legere scis nimium eruditionis habes.

  7. #17
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    Quote Originally Posted by Besoeker View Post
    My view is that your system is complicated by the number of different voltages. Your residences alone have two different voltages compared to Europe where it is all 230V.
    It really doesn't complicate things much at all. Both the 120 and 240V both come from the same panel. You can use the same cable for both. The breakers are normally snap in. The voltage to ground is just 120V. so it's considered safer that 230V to ground.

    Do you really think that idiots like we Americans could deal with it if it were complicated? We can't even learn to speak "English".
    The 95% of people that you can't trust give the other 5% a bad name.

  8. #18
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    Using a grounded conductor for current carrying purposes invites stray voltages to happen. Even if you did not use the grounded conductor as a circuit conductor anywhere on a premises, you still have some risk of stray voltages coming from the POCO's grounded conductor which does carry current.

    More modern dairy farms are much more strict on equipotential planes and bonding of things, but still are subject to outside stray voltage at times from current carrying grounded conductors elsewhere on the same utility system.

    I think we are more likely to convert to using SI (metric) units of measurement before we ever abandon grounded current carrying conductors. There is simply too many things out there designed to operate on 120 volts to just suddenly abandon those systems that have a 120 volt utilization voltage - which majority of them is not really all that feasible to ground another point in the system if you wanted to, as most are already using a "neutral" conductor as one of the 120 volt circuit conductors and grounding it results in the lowest possible potential to ground throughout the rest of the system.

    Outside of control circuits, there aren't that many systems with 120 volts that aren't already a "multiwire" system.

    277 volts is the next most popular utilization voltage with about the same issues.

    Corner grounded delta systems present this problem as well, but they are not quite so common, and equipment that is used with them can easily be used on other systems with same phase to phase voltage but some other grounded point in the system.

  9. #19
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    Quote Originally Posted by growler View Post
    It really doesn't complicate things much at all. Both the 120 and 240V both come from the same panel. You can use the same cable for both. The breakers are normally snap in. The voltage to ground is just 120V. so it's considered safer that 230V to ground.

    Do you really think that idiots like we Americans could deal with it if it were complicated? We can't even learn to speak "English".
    Very droll.................

    I didn't actually mean it is complicated. Just that having the two residential voltages complicates it somewhat compared to having just one. I suppose you could make an argument for it being twice as complicated. But I won't..........

    Yes, the risk of a fatality from being electrocuted with 230V is greater than from 120V. But then you ought to consider the risk of a loose neutral puting excess volts on say, a table lamp.
    I'm not suggesting that one system is better than the other. Just that one is simpler.
    Si hoc legere scis nimium eruditionis habes.

  10. #20
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    Quote Originally Posted by Besoeker View Post
    Very droll.................

    I didn't actually mean it is complicated. Just that having the two residential voltages complicates it somewhat compared to having just one. I suppose you could make an argument for it being twice as complicated. But I won't..........

    Yes, the risk of a fatality from being electrocuted with 230V is greater than from 120V. But then you ought to consider the risk of a loose neutral puting excess volts on say, a table lamp.
    I'm not suggesting that one system is better than the other. Just that one is simpler.
    A lot of people don't respect 120 volts. This is because they have been shocked by things supplied by a 120 circuit or at least a 120 to ground circuit, and survived, usually with little noticeable damages.

    If most common voltages here were 240 or more to ground I think there would be more respect to the dangers.

    277 to ground is a fairly common voltage and does get more respect to the dangers then 120 does. It is not as common at our homes and many smaller businesses though.

    Can't tell you how many times I have heard "it is only 110".

    Can't tell you how many times I have heard that "220 really hurts" even though most of those incidents were likely only 120 to ground incidents and they just don't realize what it was they were dealing with when they got shocked.

    Also heard many stories of how getting shocked from an open neutral is the worst, thing is there is no more then 120 volts involved a lot of the time, I think it is the fact they got hit by something they didn't expect to be "live" really plays a mind game on you to some extent.

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