Very simply, is this not contrary to the NEC? I did not think we could run wires of differing voltages in the same conduit. This is your CYA to the client.
Daryl > Well, I donât think anyone on this list is a network specialist, which > is what I would consider an expertâ¦. But⦠> > > > Running cat5 (really any data cable) parallel to a power line (especially > and AC line) is listed as a bad move in almost every installation guide I > have ever seen. Data and power are supposed to cross paths in a > perpendicular fashion whenever they get âcloseâ to each other. If the > clients wants to pay for a letter from a network specialist, just so they > can spend more money putting the right stuff in, I would just have that > done. But everything Iâve ever learned about this says that power > running in the same conduit as communications is a cardinal sin (they run > parallel, and as close as is physically possible while in the same > conduit). To borrow a phrase from Joe Lstiburek âThatâs what we call a > Barry Bonds problemâ¦..stupid on steroidsâ. > > > > The bare minimum is to make sure the cable is shielded, and the bleed wire > is terminated at a grounding point at one end only. This is the only way > there is a prayer for Ethernet signals to make the 120â journey with any > reliability. The more noise in the line, the slower the connection, as > more and more packets will get rejected and have to be re-sent until they > make it through without too much distortion, at some point the noise will > prevent any data packets from making it from A to B and you need to break > out the string and Dixie cups. > > > > The standard phone line may function, but it might sound like youâre > talking to one of the adults from Charley Brown. > > > > As for the inverter signalâ¦. I bet that would work if you use a solid > state relay that requires just a few milliamps to trigger, even 28AWG cat > 5 wire can handle that I bet. When we use a shielded cat 5 to transmit > MODBUS and a small amount of signal power, we usually use two pairs of > wire and parallel them just to give more copper for the amps to go > through. You just make sure you run the + using the striped wires from > both sets, and the - on the solid wire from both sets (or vise versa) so > that your power is truly running in twisted pairs still and so it will not > create any added noise in the cabling. > > > > When a client wants to do something like this with us and we cannot > convince them itâs a bad idea, we simply put it in writing that any > issues resulting from âXYZâ will not be covered by our warranty, as it > was done counter to industry best practices, and against our advise. > > > > With Regards, > > > > Daniel Young, > > NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 > > > > From: RE-wrenches [mailto:[email protected]] On > Behalf Of John Blittersdorf > Sent: Monday, August 22, 2016 9:26 AM > To: RE-wrenches <[email protected]> > Subject: [RE-wrenches] Cat 5 cable in 240 AC power conduit with #2 alum > entrance wire. > > > > Wrenches, > > I have a customer who has pulled a cat 5 cable through his power conduit > (2" PVC) to a new barn for about 120' and wants to use it for ethernet > and telephone. Wants me to use a pair if wires in the cable to trigger > a relay to disconnect a direct grid tie inverter (AC Coupling) when > batteries are full on his double GVFX3648 backup system He wants it in > writing from experts that it is not a good idea. Has anyone done this > and had good luck with it or have opinions? > > > > John Blittersdorf > > > > formerly owner of Central Vermont Solar & Wind > > now working for the new owner Rob Stubbins Solar > > (I get a regular paycheck and (usually) regular hours. > > _______________________________________________ > List sponsored by Redwood Alliance > > List Address: [email protected] > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > List-Archive: > http://www.mail-archive.com/[email protected]/maillist.html > > List rules & etiquette: > www.re-wrenches.org/etiquette.htm > > Check out or update participant bios: > www.members.re-wrenches.org > > _______________________________________________ List sponsored by Redwood Alliance List Address: [email protected] Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/[email protected]/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
