How to go about grounding ...


  #1  
Old 08-31-08, 02:46 PM
R
Member
Thread Starter
Join Date: Aug 2008
Location: WISCONSIN
Posts: 76
Upvotes: 0
Received 0 Upvotes on 0 Posts
How to go about grounding ...

Hi everyone:

I'm not sure if you'll totally be able to answer this question, but I thought I'd give it a try and see if I could possibly get some insights from the board.

My first question deals with protecting a phone system central processing unit. I was planning on plugging the system in to an APC battery backup unit. However, I was told that these units provide sub-par surge protection. What does the board think? I've always been very pleased with my APC units, but wanted to get the scoop on the surge end of these units.

The other question I have is about grounding a telephone connection block in a building. What's the best way to ground something in a building? I've got lots of pipes to work with, but am not sure if it's that simple.

Thanks for the help!
 
  #2  
Old 08-31-08, 04:04 PM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 13,976
Received 194 Upvotes on 170 Posts
I can't answer about the surge protection issue.

The phone lines should be bonded to the system electrical ground. They should not be connected to any nearby pipe nor should a separate ground rod be driven.
 
  #3  
Old 08-31-08, 08:28 PM
D
Member
Join Date: Jul 2008
Location: USA
Posts: 339
Upvotes: 0
Received 0 Upvotes on 0 Posts
First of all the APC is about the best protection you can get. They even guarantee it and back it up with a protection policy I believe. This is for power line surges and lightning surges, other entry points would not be protected.

The phone company typically bonds the phone ground to a nearby water pipe. If you public water and your piping is metal all the way to the street without breaks, this is about the best ground you can have but there is a lot of non metal pipe used today so this is often not an option. In that case you would have an alternate grounding method, probably a rod or two driven in the ground. The internal piping system, if it is metal should still also be bonded to the electrical ground.

I would not just connect the ground from the incoming phone line lightning arrestor to an outlet ground. While the outlet grounds are good for electrical grounding they are not for lightning. You should have a direct and short as possible connection to a ground source. Metal water piping that is continuous is good because it is very large and usually has a low impedance to ground.

I am a radio operator and we would not even think of using a power ground as a radio frequency ground. Lightning has energy clear up to 1000 Mhz or more. So it is a completely different animal than 60 Hertz AC grounding.

The important thing is bonding. Grounds should be bonded and you can't have to many especially for lightning.

Of course if you have fiber phone service (FIOS) then you do not have to worry about phone line lightning or surge entry. There is no conductive path to the street.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: