On 2010-03-17, Alby <[email protected]> wrote: > On 16 Mar, 15:03, unruh <[email protected]> wrote: >> On 2010-03-16, E-Mail Sent to this address will be added to the BlackLists >> <[email protected]> wrote: >> >> > Alby wrote: >> >> (Garmin GPS 18 LVC, 5m). >> >> >> So can I assume the extra thin black wire is just an >> >> ?additional ground wire? >> >> > One black wire is the power common, >> > ?another black wire is the data common, >> > ?the third black wire is a shield drain. >> >> What is a "shield drain" and how do you know this? It is just off the >> top of your head, or is there some more authoritative source for this >> info? >> >> (anyway, it sounds like there is nothing to prevent you from tying all >> grounds together, unless the power comes from a source with a separate >> ground from what the data ground is tied to, which could give bad ground >> loops. In that case I would assume that you would tie the shield ground >> to the power ground. >> >> > > > > I think I figure it out. The extra black wire on my GPS Unit is > because my > model is a Garmin GPS LVC, 5m. The typical unit is a 3m. Meaning my
So are mine (2 of them) GPS18LVC 5m units. And they onlyhave 2 black wires. > cable length > is 5 meters long, while the standard is 3 meters. Given the extra > distance in my > cabling, the additional black wire is performing the function of an > electromagnetic shield. > The poster who mentioned "drain wire" jogged a memory. > > > > drain wire definition - telecom > A wire wrapped around or part of a shield within a cable that reduces > the resistance from any point on the shield to ground. A drain wire > serves to complete an electrical circuit from the shield, thereby > carrying extraneous electrical noise to ground and away from the > circuit or system the shield is intended to protect. See also ground, > ground wire, and shield. > http://www.serialphy.com/multi-conductor-cable.bmp _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
