<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">
Aaron,
<div class=""><br class="">
</div>
<div class="">I think you didn’t get that the lineman was talking about equipotential grounding. The school of “waiting for a few more trucks to arrive” probably doesn’t get into the full depth of the subject :)</div>
<div class=""><br class="">
</div>
<div class=""> -mel</div>
<div class=""><br class="">
<div>
<blockquote type="cite" class="">
<div class="">On Aug 30, 2021, at 10:46 AM, Aaron C. de Bruyn <<a href="mailto:aaron@heyaaron.com" class="">aaron@heyaaron.com</a>> wrote:</div>
<br class="Apple-interchange-newline">
<div class="">
<div dir="ltr" class="">During the February 2021 storm that swept through the US, power got knocked out on my rural street due to a tree coming down and taking out a pole.
<div class=""><br class="">
</div>
<div class="">While they were waiting for a few more trucks to arrive with a replacement pole, I got to ask them a few questions. They said it's standard practice for them to ground on both sides exactly for the reason that someone might accidentally connect
a generator. They open the nearest switch on the upstream side, test to make sure the line is dead, install grounds on all the wires, then test the downstream side and attach grounds to all the wires, effectively making the work zone an isolated segment.<br class="">
</div>
<div class=""><br class="">
</div>
<div class="">I doubt it's "if you follow every step perfectly at all times and never make a mistake".</div>
<div class="">There are usually redundancies built-in when it comes to safety. i.e. what's the point of installing grounds on the upstream side if you have the switch open? If the lines are de-energized, why wear gloves? If you're doing all that, why carry
an AED?</div>
<div class=""><br class="">
</div>
<div class="">-A</div>
</div>
<br class="">
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Mon, Aug 30, 2021 at 10:19 AM Warren Kumari <<a href="mailto:warren@kumari.net" class="">warren@kumari.net</a>> wrote:<br class="">
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="ltr" class="">
<div dir="ltr" class=""><br class="">
</div>
<br class="">
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Mon, Aug 30, 2021 at 12:47 PM Aaron C. de Bruyn via NANOG <<a href="mailto:nanog@nanog.org" target="_blank" class="">nanog@nanog.org</a>> wrote:<br class="">
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="ltr" class="">I've been following the thread.
<div class="">If I'm dumb enough to back feed through the transformer into the downstream side of the downed line, how is it going to be a problem if linemen are grounding the phases on *both sides* of the work area.</div>
</div>
</blockquote>
<div class=""><br class="">
</div>
<div class="">I suspect that there is a non-zero amount of "in an ideal, perfect world, when all of the wires are simply lines on a piece of paper, and you can look at them from the comfort of your office chair, this is easy" - but, in the real world, linesmen
are rushing about and trying to get the lights back on, cut through the big ash tree that is wedged between the oak and the pole, etc. Even the nice idea of "well, just take the conductos and tie 'em to ground" means that you need to go trudging through hedges
and vegetation and tree limbs and lions and tigers and bears, often while it is pissing down with rain or baking hot.</div>
<div class=""><br class="">
</div>
<div class="">I guess I'm missing how we've moved from the "some people are putting their lives on the line, let's try to make their life less dangerous" into a "weeeeell... if they simply followed these set of steps perfectly at all times, and never made a
mistake they'd be fine."</div>
<div class="">This is NANOG -- I'm sure that we've all followed a set of steps perfectly and still managed to redistribute BGP into the IGP, or apply an ACL and lock ourselves out of a box, or types "show run" and watched the router randomly reboot. Now consider
this, but with the added drama of potentially ending up dead...</div>
<div class=""><br class="">
</div>
<div class="">W</div>
<div class=""> </div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="ltr" class="">
<div class="">That's what Ben seemed to be implying.</div>
<div class=""><br class="">
</div>
<div class="">-A</div>
</div>
<br class="">
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Mon, Aug 30, 2021 at 9:09 AM Mel Beckman <<a href="mailto:mel@beckman.org" target="_blank" class="">mel@beckman.org</a>> wrote:<br class="">
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="auto" class="">Aaron,
<div class=""><br class="">
</div>
<div class="">If you read back in this thread (using the NANOG mailing list archive), you’ll find this has been explained in great detail. In a nutshell, phase grounding won’t help if a generator is energized from the customer end, and this technique was discontinued
in the 1970s due to the many deaths that resulted.<br class="">
<br class="">
<div dir="ltr" class=""> -mel </div>
<div dir="ltr" class=""><br class="">
<blockquote type="cite" class="">On Aug 30, 2021, at 9:02 AM, Aaron C. de Bruyn via NANOG <<a href="mailto:nanog@nanog.org" target="_blank" class="">nanog@nanog.org</a>> wrote:<br class="">
<br class="">
</blockquote>
</div>
<blockquote type="cite" class="">
<div dir="ltr" class="">
<div dir="ltr" class="">
<div dir="ltr" class=""></div>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Mon, Aug 30, 2021 at 7:35 AM Lady Benjamin Cannon of Glencoe, ASCE <<a href="mailto:lb@6by7.net" target="_blank" class="">lb@6by7.net</a>> wrote:<br class="">
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div class="">
<div dir="auto" class="">
<div dir="auto" class="">Yes, this is a real and dangerous problem. Today. Even with grounding I’m afraid. Source: I’ve been working in an engineering capacity for 27 years and I have the license you’d need to build a nuclear power plant. </div>
</div>
</div>
</blockquote>
<div class=""><br class="">
</div>
<div class="">Would you care to educate me on this?</div>
<div class="">If you ground the phases on both sides of the work-site, how are you going to end up being a better path to ground?</div>
<div class=""><br class="">
</div>
<div class="">-A </div>
</div>
</div>
</div>
</blockquote>
</div>
</div>
</blockquote>
</div>
</blockquote>
</div>
<br clear="all" class="">
<div class=""><br class="">
</div>
-- <br class="">
<div dir="ltr" class="">
<div dir="ltr" class="">The computing scientist’s main challenge is not to get confused by the<br class="">
complexities of his own making. <br class="">
-- E. W. Dijkstra</div>
</div>
</div>
</blockquote>
</div>
</div>
</blockquote>
</div>
<br class="">
</div>
</body>
</html>