steve@aplvax.UUCP (04/26/84)
<> Has anyone had experience running Ethernet cable in conduit? We are probably constrained to do this in a particular installation, and wondered if anyone ran across any problems (such as access to taps, etc.) Thanks in advance for any info. Steve Kahn Johns Hopkins Applied Physics Lab
james@umcp-cs.UUCP (04/27/84)
We have ethetnet cable running through a conduit under a dormitory quad to get from one bldg to the next. But no taps needed along that stretch of cable. I've heard of NSA designs for an ethernet inside poison-gas-filled conduit, pressurized. I don't know whether they actually went through with this. --Jim
ron@brl-vgr.ARPA (Ron Natalie <ron>) (04/27/84)
NSA runs wires in conduits in unsecured area pressurized with gas but not because they're trying to poison people. There is a detector at the end of the conduit that detects pressure loss (presumably someone cutting into the conduit) and shuts off power to the computer. -Ron
lmc@denelcor.UUCP (Lyle McElhaney) (04/27/84)
We were forced to run part of our Ethernet cable through conduit, due to a very sticky fire code. The problems that we encountered included how to install a tap in a box without unduly bending the cable, getting the black marks to line up with the boxes, and having to remove terminations to get the cable pulled, and then putting them back on. If a retap is ever required in a box, we may have to punt. Answers: - Measure the conduit runs between boxes carefully. - Get the holes in the boxes placed to minimize cable bending. - Get *big* boxes to put the tap in. - On transciever cables, use a pin removal tool to remove pins from the 15-pin connector shell before pulling the cable through. Don't splice a transciever cable. - You'll need to remove one terminator on the coax, pull it, and then install the terrminator back on. You can splice a coax, using two male ends and a female-female adapter. - Beware, throughout, that Ethernet specs do not allow a bend in the coax togo below a 8 inch radius (I believe that's the number). Our cable was installed pretty badly (small boxes for the transcievers, bends, spliced transciever cables), and we had to go to a lot of trouble to prove we had defective equipment rather than a bad installation when troubles arose. The net seems to work well in spite of all this, but its best to play it safe. -- Lyle McElhaney (hao,brl-bmd,nbires,csu-cs,scgvaxd)!denelcor!lmc