http://xkcd.com/927/ -----Original Message----- From: Af [mailto:af-boun...@afmug.com] On Behalf Of Adam Moffett Sent: Monday, June 29, 2015 6:20 PM To: af@afmug.com Subject: Re: [AFMUG] wire color standards
Ok, then I found this: http://www.graphicproducts.com/articles/wire-color-coding.php Which says DC with no ground is red/black. DC with negative ground is red/white DC with positive ground is white/black I guess it goes to show: "the great thing about standards is there are so many to choose from." On 6/29/2015 5:47 PM, Mark Radabaugh wrote: > I have seen -48V done both ways - black as 0V and red as 0V. Red as 0V > seems to be more common. > > Both are confusing if you are not familiar and I usually resort to getting > out a voltmeter to check before connecting anything. > > Black as -48V is bad if you expect black to be at ground and not have any > potential. Red is bad as ground if your crew thinks hooking up batteries > means they should connect the + side of the battery to the red wire. Makes > for a big boom when you hook the -48V rectifier to the +48V battery. Don’t > ask how I know that. > > I like Orange for -48V myself but of course we didn’t consistently use that - > so I still have to get my voltmeter out. > > Mark > > >> On Jun 29, 2015, at 5:35 PM, Adam Moffett <dmmoff...@gmail.com> wrote: >> >> in DC I've been doing red for positive and black for negative for my entire >> life.....read that in a book when I was in elementary school. >> >> Do they do things differently with -48? It just occurred to me that a >> different color code would be an easy way to alert people that they're >> seeing positive ground. >>
