This may just be semantics, but is an electro-static discharge the same thing as electro-magnetic pulse?
Tom Haynes HopeWireless Network [EMAIL PROTECTED] http://www.tomhaynes.net -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Dan Petermann Sent: Sunday, June 29, 2003 1:16 PM To: [EMAIL PROTECTED] Subject: Re: [smartBridges] Grounding?! You are kidding right? The simplest and easiest way to prove this is to listen to AM radio during an electrical storm. The static you hear every time lightning strikes is the result of the E.M. P. (ElectroMagnetic Pulse) from a massive electrical burst. Lightning will produce radio waves across a huge portion of the electromagnetic spectrum. Dan Petermann Wyoming.com At 10:01 AM 6/29/2003 -0500, you wrote: >I thought we all had a long conversation not too long ago and was >determined that Lightning CAN NOT cause E.M.P. > >Michael > >----- Original Message ----- >From: "Nish Park" <[EMAIL PROTECTED]> >To: <[EMAIL PROTECTED]> >Sent: Sunday, June 29, 2003 9:45 AM >Subject: RE: [smartBridges] Grounding?! > > > > Wow. This are nice tips John. We will make sure to include them in > > our product documentation to help others. Thanks. > > > > Nish > > > > > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] On Behalf Of John Hokenson > > Sent: Sunday, June 29, 2003 3:01 PM > > To: '[EMAIL PROTECTED]' > > Subject: Re: [smartBridges] Grounding?! > > > > I've been involved with designing and installing communications > > systems for over thirty years, are here is my take on the proper > > installlation and grounding of the SmartBridge units (and WISP > > equipment in general).... > > > > TOWER TOP ACCESS POINTS/BRIDGES > > > > 1. In any area that is prone to lightning, grounding and protection > > of > > the antenna port is a must. With the units that are fed from the > > ground with PoE (power over ethernet) and an antenna jack, > > first--screw a high quality lightning supressor on the N-female jack > > on the radio--the Polyphaser PSX-ME is what I prefer. It has a male > > connector to screw onto the radio and a female for attachment of the > > antenna cable. Since the case > > of the radio is plastic and does not ground to the tower (not really a > > good > > idea in my opinion but we're stuck with it), use a grounding kit to > > securely > > bond the body of the protector to the metal leg of the tower. > > 2. I am suspecting that many of the radio failures are due to induced > > emp > > from nearby lightning strikes on the ethernet cable itself which is > > acting > > as an antenna to pick up the pulse. For this reason I suggest the use > > of > > outdoor shielded cat5--the kind with icky pick embedded in the inner > > layer > > among the pairs, a first pvc insulation layer, an aluminum jacket with > > additional icky pick and finally an outer PVC jacket. At the radio end, > > terminate the connection as close as you can get it to the radio--the > > new > > style radios I would terminate it in the weatherproof splice box. You > > will > > need a bonding kit to attach a ground wire to the aluminuum > > jacket--these > > are commonly made by 3M and available from Graybar. Using a #10 or > > larger > > wire attached to the stud on the grounding kit, bond the shield to the > > leg > > of the tower, keeping the ground wire as short as possible. The best > > way I > > have found to do this is to assemble the grounding kit to the shield > > about > > 6" from the end of the cable where the pairs will be attached, then > > slide > > some Panduit DB shrink with hot glue sealant inside over the splice and > > shrink it down to weather seal the bond. Since you also need the ground > > for > > the antenna protector, you can clamp a phospher bronze ground clamp to > > the > > leg of the tower directly below the radio and attach both the ground > > from > > the antenna protector and the cat5 ground to the same point. Graybar > > has > > the Panduit shrink and ground clamps as well. > > 3. Install another bonding kit on the cat5 where it leaves the tower, > > again you can seal it with Panduit DB shrink. > > 4. If the run up the tower is more than 150' (50M) or so, I would > > probably bond the shield in the middle of the run as well. > > 5. Where the cat5 terminates, again bond the shield to a ground....#8 > > or > > larger copper wire back to the tower ground is preferable, lacking that > > the > > building ground....and make sure someone has bonded that to the tower > > ground > > with #6 or larger copper. > > 6. Lastly, between the end of the shielded cat5 and the PoE injector, > > install a good quality PoE surge suppressor--Motorola makes a nice one > > for > > their Canopy products and is available from Tessco for about $40. Make > > sure > > the ground stud on it is tied to the same ground feeding the end of the > > cat5 > > shield. > > 7. Code generally requires that the protector beinstalled where the > > cat5 > > enters the building, so the place to terminate the shielded cat5 and > > install > > the Motorola cat5 protector is on the outside of the wall, and > > transition > > there to normal cat5 in to your power injector. > > > > ROOFTOP ACCESS POINTS/BRIDGES > > > > 1. Many times either an access point or cpe radio will be installed > > on > > the top of a commercial building or home. The same rules apply with > > some modifications because of the installation. > > 2. If it is a customer radio that is not as critical as an access > > point, > > you may choose to dispense with the lightning supressor on the > > antenna--but > > DO at the minimum bond the shield of the coax to the galvanized metal > > support mast or support structure or DSS mount. One option for this > > would > > be to loosen the lock nut for the N female connector on the radio and > > install a piece of sheet metal under the nut to attach a ground > > wire--we've > > done this and it works well. > > 3. You still need to use shielded cat5 and bond the shield to the > > common > > antenna ground point as described in the previous section on tower > > grounding. > > 4. Since the antenna support is most likely not grounded in this > > instance, you need to attach a #6 copper wire to the support stucture > > (the > > 5/16 bolts securing the tripod to the mast is a good spot) and bring it > > down > > along with the cat 5 to where things enter the building. > > 5. Attach the #6 wire to the ground lug on the cat5 protector, along > > with > > the cat5 shield, then continue to the closest attachment point to the > > building system ground. > > > > INDOOR ACCESS POINTS AND BRIDGES > > > > 1. In those cases where the installation is using an indoor unit with > > coax out to an outdoor antenna, I would direct you to a typical > > installation of a certified SmartBridge CPE: > > http://www.vircom.net/pictures/res-install/res-install.htm > > 2. In the case of an indoor access point, the only change I would > > suggest > > is installation of a Polyphaser PSX instead of simply a bulkhead ground > > at > > the entrance point. > > > > Hope this helps a few of you out there avoid unnecessary failures. > > > > ========================================== > > John Hokenson, Operations Manager > > VIRCOM.NET > > reply to: [EMAIL PROTECTED] > > 425-558-0674 bellevue > > 425-432-8172 king county > > 206-341-9421 seattle > > 800-806-7446 toll-free > > 425-432-8173 fax > > WWW.VIRCOM.NET > > giving you the world since 1994 > > ========================================== > > ----- Original Message ----- > > From: "David Berndt" <[EMAIL PROTECTED]> > > To: <[EMAIL PROTECTED]> > > Sent: Saturday, June 28, 2003 9:50 PM > > Subject: [smartBridges] Grounding?! > > > > > > > A bit of a mid-night rant here. > > > > > > I've been thinking on a lot of the failures we hear talked about > > > here > > on > > > the list, the quesitons about lightning, potential lightning > > > strikes, lightning striking near by. Alot of the answers seem to > > > be a > > combination > > of > > > finger crossing and some black magic. > > > > > > So what I'd like to see to rectify some of these issues is > > > smartbridge publish a document about proper grounding. Where do we > > > need > > grounds/surge > > > protectors/lightning arrestors, the differences between them, etc. > > > > > > I know these things are all dictated by the local building code > > > and > > the > > > like wherever you happen to be using the product. But how about > > > some > > sort > > > of a document that is intended as a bare minimum/recommended > > > practices document to get all the installs to be put together in a > > > fairly > > similar > > way > > > and help correct some of the new newbie mistakes and take a bit of > > > the black magic out of this. > > > > > > This could be a fairly simple diagram of a few different sample > > > setups > > of > > > the outdoor equipment. I am especially interested in the total > > equipment, > > > is there a polyphaser in there? Should the cat5 be grounded when > > > using sheilded cat5, otherwise? Surge protector on the cat5? > > > before/after > > the > > POE > > > device? etc etc. > > > > > > A recommended parts list wouldnt be horrible either. I do not want > > > to > > see > > > this enforced, but more documentation and standardization would > > > make > > things > > > clearer for everyone, provide a quick way to answer peoples > > > questions > > and > > > maybe make everyones systems a bit more stable. > > > > > > Hope that made some degree of sense. > > > > > > Dave > > > > > > The PART-15.ORG smartBridges Discussion List > > > To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe > > smartBridges <yournickname> > > > To Remove: mailto:[EMAIL PROTECTED] (in the body type > > > unsubscribe > > smartBridges) > > > Archives: http://archives.part-15.org > > > > The PART-15.ORG smartBridges Discussion List > > To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe > > smartBridges <yournickname> To Remove: mailto:[EMAIL PROTECTED] > > (in the body type unsubscribe > > smartBridges) > > Archives: http://archives.part-15.org > > > > > > The PART-15.ORG smartBridges Discussion List > > To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe >smartBridges <yournickname> > > To Remove: mailto:[EMAIL PROTECTED] (in the body type unsubscribe >smartBridges) > > Archives: http://archives.part-15.org > > > > > > >The PART-15.ORG smartBridges Discussion List >To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe >smartBridges <yournickname> >To Remove: mailto:[EMAIL PROTECTED] (in the body type unsubscribe >smartBridges) >Archives: http://archives.part-15.org The PART-15.ORG smartBridges Discussion List To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe smartBridges <yournickname> To Remove: mailto:[EMAIL PROTECTED] (in the body type unsubscribe smartBridges) Archives: http://archives.part-15.org The PART-15.ORG smartBridges Discussion List To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe smartBridges <yournickname> To Remove: mailto:[EMAIL PROTECTED] (in the body type unsubscribe smartBridges) Archives: http://archives.part-15.org
