On Saturday 14 July 2018 03:13:49 John Dammeyer wrote: > > > > That's pretty much standard these days. > > > > > > I don't understand the desire to connect two lines together > > > because they 'seem' to be of the same magnitude. 0VDC is Not > > > equal to Gnd Many systems will have multiple 5V power lines, > > > heavy, light, designated. Do you want to link all those up too? > > > > Generally you want you power supply and logic nd safety grounds to > > be separate. But at ONE and one one point would you connect them. > > > > What's happening here is that some "grounds" are carrying current > > exactly equal to the power supply current and unless yu are using > > "super conductor" > > cable cool with liqi=ud helium there *will* be a non-zero voltage on > > the "ground" cable. That is the problem with interconnected > > grounds, all those return currents and by Ohm's law "return > > voltages". But if yu do connect safety and return grounds at ONE > > point current can't flow. But this is hard to do. Really hard if > > there are multiple 3-prong power plugs. > > And then there's impedance. That thick conductor that measure almost > zero ohms with a meter compared to 0.5 ohms of the thin one suddenly > has a very high impendence to high frequency noise bursts. So the > high current spikes don't go through the thick but instead through the > thin. > > John > Not exactly 100% correct John. High frequencies are generally carried only by current flow at the skin of a conductor. And the large conductor, while having some rise in impedance, is still the better conductor because the smaller wire has far less surface skin area, raising both its impedance and its ohmic effects faster than the big wire.
> > ---------------------------------------------------------------------- >-------- Check out the vibrant tech community on one of the world's > most engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users -- Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
