| [Bus. Ops] CPE grounding 'Poll' I am about to form a relationship with a local wisp
They currently do not ground, in any fashion, their installs
I am pushing for ethernet grounding but because I am 'experience challenged' with RF networks, am reluctant to push too hard because they don't want to spend the $$
My gut says to ground and I find it hard to ignore
What do you all see/do in the field?
Any comments on what is typical these days with 5.3 and 5.8 CPE - concerning grounding the cable?
I have proposed the Motorola 300SS
Any thoughts?
Thanks |
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robbinPremium,MVM
join:2000-09-21
Leander, TX
kudos:1 | I ground EVERY install according to standards. I have used the Motorola 300SS and more recently the 600SS. Motorola has some good literature regarding what is required according to the NEC (National Electric Code). I would require them to ground according to the NEC. |
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| This is not even a "should I/shouldn't I" type question. All cpe installs must be grounded to conform with NEC/NFPA. No questions asked. All POE lines should be connected to an outdoor mounted protector and this protector should be bonded to the utility ground with solid #10 AWG. Period.
As for protectors, if you are using Canopy equipment you should use the 600SS as your protector. For other vendors I would suggest using what they specify or look at the POE protectors that are offered from Transtector. Their POE24 and POE48 units are very similar to the Motorola 600 units.
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"No job is so important, and no service is so urgent that we cannot take the time to perform our work safely."
-- AT&T, Your World, Destroyed.
--Safety One Tower Rescue Certified
--LLigetfa:"Wimax is like teenage sex. Everyone talks about doing it." |
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| reply to Liberty
Thanks... |
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lutfulPremium
join:2005-06-16
Ottawa, ON Reviews:
 ·TekSavvy DSL
| reply to Liberty
said by Liberty:I am pushing for ethernet grounding but because I am 'experience challenged' with RF networks If you want to save the house, you just protect the CAT5 entry point using a good quality PoE surge protector which is grounded according to applicable codes and common sense ... 
But if you also want to save the remote equipment, you have to add robust surge protection on Ethernet and all RF ports. If you skip a single surge entry point, you are essentially willing to sacrificing the device, so don't bother at all. 
Also, the gound lugs of all protectors need to be bonded together at the same point on metal enclosure. Finally the whole system should be bonded to (well-grounded) tower body using either the mounting mechanism or a short grounding strap.  |
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| said by lutful:Also, the gound lugs of all protectors need to be bonded together at the same point on metal enclosure. Finally the whole system should be bonded to (well-grounded) tower body using either the mounting mechanism or a short grounding strap. The question was focused on CPEs. What do you do for items such as a PS2 in an all plastic shell not on a tower, but on a J-pole? There are no grounding points on that radio.
Steve |
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| reply to Liberty
said by Liberty:I am about to form a relationship with a local wisp They currently do not ground, in any fashion, their installs I am pushing for ethernet grounding but because I am 'experience challenged' with RF networks, am reluctant to push too hard because they don't want to spend the $$ My gut says to ground and I find it hard to ignore What do you all see/do in the field? Any comments on what is typical these days with 5.3 and 5.8 CPE - concerning grounding the cable? I have proposed the Motorola 300SS Any thoughts? Thanks It's a simple matter of liability and safety. Not following NEC/NFPA codes for grounding means that if the radio/cabling takes a hit they are liable for any and all damage including loss of life that can occur and their liability insurance company will not cover the claim in most cases.
The secondary benefit is that I have seen that without grounding the you can and will fry CPE meaning more truck rolls and higher support costs. |
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EMC_guy
join:2007-10-13
Sharbot Lake, ON | reply to steve_NVa
said by steve_NVa:What do you do for items such as a PS2 in an all plastic shell not on a tower, but on a J-pole? There are no grounding points on that radio. You must still provide surge protection on each conductor entering! The protector should be located close to the building safety ground (or equivalent point) so you can bond using short grounding cable or strap.
But please do not run a long "bonding wire" to such devices. You will be liable for damages. !!! |
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| said by EMC_guy:You must still provide surge protection on each conductor entering! The protector should be located close to the building safety ground (or equivalent point) so you can bond using short grounding cable or strap. But please do not run a long "bonding wire" to such devices. You will be liable for damages. !!! I got the penetrating connector rule. But the codes say "poles" should be grounded as well. Do we have to run a ground to an otherwise isolated jpole on the roof?
I may be misunderstanding, but isn't that the "bonding wire"?
Steve |
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| Your antenna masts should be bonded to the same location as your entrance protector. This is all outlined in NEC. Long bonding wires could occur but this is of no concern because code requires them.
Code says Do "X" so you do X and call it a day. |
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EMC_guy
join:2007-10-13
Sharbot Lake, ON
1 edit | reply to steve_NVa
said by steve_NVa:But the codes say "poles" should be grounded as well. Do we have to run a ground to an otherwise isolated jpole on the roof? Be aware that to avoid the smaller risk of the pole accidentally touching a live wire, you will be taking a bigger risk of burning down the house by dangling a long bonding wire along the walls and roof! Post-mortem of lightning-related house fires show flash-over to be the root cause 99% of the time!!!
Poles should not be mounted on the middle of roofs unless you can directly hook it up to existing (professionally designed) structural grounding system using just a few feet of wire/strap!
Otherwise, offset-mount the pole on the side of the house so that you can route heavy-gauge grounding wire straight down to real ground - make sure it stays 12 inches away from roof-edge and wall. Terminate to a properly installed grounding system right at the bottom. You can meet code requirements by bonding the AC safety ground to this secondary grounding point - ideally underground! |
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| said by EMC_guy:But please do not run a long "bonding wire" to such devices. You will be liable for damages. !!! said by EMC_guy:Be aware that to avoid the smaller risk of the pole accidentally touching a live wire, you will be taking a bigger risk of burning down the house by dangling a long bonding wire along the walls and roof! said by EMC_guy:Otherwise, offset-mount the pole on the side of the house so that you can route heavy-gauge grounding wire straight down to real ground - make sure it stays 12 inches away from roof-edge and wall. Terminate to a properly installed grounding system right at the bottom. You can meet code requirements by bonding the AC safety ground to this secondary grounding point - ideally underground! Have to admit I'm not clear about your advice. Are you saying don't ground a pole if it is not offset-mounted on the side wall? Or don't mount anything at all if it is not on the side?
We have limitations by physics occasionally, and sometimes as much as we try to convince the radio otherwise, we only get a usable signal in certain places on the roof, such as top center or maybe some other highest point. Is there a recommended grounding solution for a jpole mounted CPE at the worst (grounding wise) possible location rooftop?
Steve |
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| reply to Liberty
I wonder if someone can point me to such grounding laws in Canada Electrical Code. (for antenna or sat dish)
I think we fall in that category.
My buddy is one of the largest installers of sat dish for Bell Canada (about 400 installs a year) and they ground nothing. They have more than ten installers so add it up.
He says they have never had a case where they were held liable for anything. Yes they have lost a few lnb's. |
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| reply to Liberty
Try NEC 810.15 and NEC 810.20 |
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| sorry does not apply to me:
neither does this one
»www.eng-tips.com/viewthread.cfm?···1&page=6 |
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lutfulPremium
join:2005-06-16
Ottawa, ON Reviews:
·TekSavvy DSL
| reply to steve_NVa
said by steve_NVa:We have limitations by physics occasionally, and sometimes as much as we try to convince the radio otherwise, we only get a usable signal in certain places on the roof, such as top center or maybe some other highest point. Obviously you could get same or even better RSSI at other points along the beam path towards the AP. So the problem is really physical access rather than physics.
said by steve_NVa:Is there a recommended grounding solution for a pole mounted CPE at the worst (grounding wise) possible location rooftop? Assuming the home is not currently protected against lightning strike, your CPE installation has to do a very good grounding job which is very difficult with a single air terminal and down-conductor. 
Please read this first (»www.comm-omni.com/polyweb/rooftop.htm) and old posts too. |
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| reply to steve_NVa
said by steve_NVa:... What do you do for items such as a PS2 in an all plastic shell not on a tower, but on a J-pole? There are no grounding points on that radio. I may be wrong about that. The mounting frame on a PS2 may be a ground point, I've never disassembled one to find out.
Is the applicable code for most CPE installs NFPA 70 or NFPA 70A? 70A is specific for 1 or 2 family dwellings. Its been awhile since I worked with these and forget if 70 is a superset containing 70A, or 70A diverges from 70.
Steve |
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 nunyaWho is John Galt?Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:5
 ·Charter
 ·voip.ms
| reply to thewisperer
You'll notice CSA C22.1 always lags the NEC by one year. Since CANENA, Canadian and U.S. codes closely resemble one another. I'm not saying CSA C22.1 is a photocopy of NFPA 70, but they are quite similar. You'll also notice the NEC NFPA 70 now carries the title "International Electrical Code Series" and has been using standard + metric units for some time. I would expect to see a joint publication in the next few cycles.
Grounding and bonding are still grounding and bonding, whether you are in the U.S., Canada, or Timbuktu. If you are not doing it, you are putting yourself, your livelihood, your customers lives, and their property at risk. It may seem petty and negligible at the time of install, but it can turn into a big deal with one strike / surge / malfunction.
I'm surprised this still comes up so often. This should be a no-brainer by now. You just do it.
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Looks like Reverend Wright got his wish - God Damn America. |
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 superdogI Need A DrinkPremium,MVM
join:2001-07-13
Lebanon, PA | said by nunya:Grounding and bonding are still grounding and bonding, whether you are in the U.S., Canada, or Timbuktu. If you are not doing it, you are putting yourself, your livelihood, your customers lives, and their property at risk. It may seem petty and negligible at the time of install, but it can turn into a big deal with one strike / surge / malfunction. I'm surprised this still comes up so often. This should be a no-brainer by now. You just do it. While I agree with (and respect)nunya, I am going to go out on a limb and add some insight as to why this subject comes up over and over again.
For those of us who do nothing but wiring for a living (I.E. electrician, circuit designer, EMF engineer etc.), you are abreast of all the newest codes, changes and other issues that come along with your line of work. Anything you do do comes under the scrutiny of your peers which includes code enforcement officers, senior engineering staff and a host of other individuals that make it a full time job to critique your work.
Even this situation has its ups and downs, as depending on how abreast the inspector is of current guidelines, you may have done it correctly, yet you are told to change it to something else because of ignorance or perhaps interpretation by the inspector of the wording in the paragraph. I have been on job sites where two separate engineering firms have delayed a job for over a week because neither side can agree on what the definition truly says and they had to bring in an "outside opinion" to settle the argument. 4 months later, it had to be changed yet again because another "Expert" working for the municipality had his own version of how it should be done, and in order to get the occupancy permit, the builder had no choice but to change it.
While this is an extreme example, it does happen. As WISP's, we are going on roofs every day and see all types of things that have been done by individuals before us. I can not personally tell you how many different things I have seen done by TV antenna, satellite and HAM radio operators/installers. Some of these things are right, some are wrong, but to the untrained eye, we have no idea what to think?
There is also the human factor that constantly asks, "I wonder if I could get away with doing X, because if I do it with Y, I can save $50 and 2 hours of time?". Lets face it, in a competitive world, we all know we ask ourselves this question over and over and over again, especially on a day when we are over worked, over stressed, constantly broke and the phone is ringing off the hook.
With all of these factors in mind and the fact that every day this forum is read by new individuals trying to come up with answers and also trying to be budget conscious, I would be amazed if the grounding question WASN'T asked 3 or 4 times a week. The human mind is constantly telling us that somewhere, somehow, a cheap shortcut just HAS TO BE OUT THERE, we just didn't ask the right person yet!, LOL.
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»www.wavecrazy.net
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said by nunya:This should be a no-brainer by now. You just do it. I'm not intending to argue, just asking for opinions about how best to do it.
Steve |
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