Grounding and Bonding for Video Surveillance

By: Brian Rhodes, Published on May 04, 2015

One of the most misunderstood and sloppiest elements of network design, grounding and bonding mistakes can lead to big problems.

In this note, we explain the key elements involved including:

  • Differences between grounding and bonding
  • The purpose of bonding and grounding in surveillance
  • Published standards covering bonding and grounding
  • Rack ground traps
  • Chassis screws/bolts
  • Third plug prong
  • Camera side grounding
  • Cable shield grounding
  • Ground loop problems

*** ** *** **** misunderstood *** ********* ******** of ******* ******, ********* and ******* ******** *** lead ** *** ********.

** **** ****, ** ******* the *** ******** ******** including:

  • *********** ******* ********* *** bonding
  • *** ******* ** ******* and ********* ** ************
  • ********* ********* ******** ******* and *********
  • **** ****** *****
  • ******* ******/*****
  • ***** **** *****
  • ****** **** *********
  • ***** ****** *********
  • ****** **** ********

[***************]

Grounding ** ******* *********

********* *** ******* **** electricity ******* *** **** of ***** **********, ********* and ******* ** *** ******** of ********** ************ ********* equipment ** ** ********** point

  • ********* (**** ****** ********):  ********** ********** ********* directly ** * *** impedance **** ** *** earth. 
  • *******: ******* ******** *** potentially ********* ********* ********. While *** ********** '********', bonding ********* ** **** to * ****** ***** ground *****, ******* * bus *** ** ****** electrode.

***********, ********* *** ******* describe ********* ***** ** the **** *******; * grounded ****** ** *** goal, *** ******* ** the ******* ** ********** gear ******** *** **** purpose.

*******

*** ********* ** ******* and ********* ** * surveillance ****** ** *** fold:

  • ******: ******* ***** ** in ****** ******* **** electricity, ** *** ******* errant ********.  *** **** way ** ******* *** metallic *******, **********, *****, or ******* **** ***** an ************* **** ** to ****** ** ** bonded *** ********* ** an ***** ******.  **** ethernet ******** *** ******* or ****** ***** *** deadly ********, *** *** general ********** **** ***** ** high-voltage ******* **** ***** to ***-******* ****.
  • ****** *********: **** ** ******** by **** ********* *** bonding. **** ***-********* ******** can ******* ******* *** quality *** ************ ** electrical ********, ******* ** ethernet *******. ** * lesser ****** **** ******, ground ******** ** ****** for ***** *********** ********** currents.

** * ******* ************ system, *** ** *** devices **** *** ** close ********* ** ****-******* sources - **** ******** switches ** ******* ******* into **** **** *******, and *** ****** *** other ******* ********* ** that ********* - **** to ** ******** ********, and ******* ** ********* the ********** ****** ** doing **.

Published *********

****** ********* *** ******* for ******* ******** ******* are ********* ** *** primary *********:

  • ***-***: ** ********** ****** applies ** **** ****** designs, **** ************* ********* minimum ********** *** ********* within * ******** ******* utility.  
  • ***-***-*/*: **** *********** ************ describes *** ******* ** grounding *** ******* ******** by ***-***.

******** **** ** ***** documents **** *** ***** of *** ************ ******* are ******** ****** *** grounded, ********* *** ***** methods ********* *****.

Surveillance ****** *********

*** ***** ********, ***** major ***** ** ********* and ******* ******* *** employed:

  • **** ****** ****
  • ******* ******/*****
  • ***** **** *****

** *******, *** ** all ** ***** ******* should ** **** ***** presented. ***** ******* **** on *** ************ *** proper ************ ** * formal ***** ****** ***** designed **** *** ************* and ********** ***** ** a ********. ** **** cases, **** **** ** readily ********* ****** * data ****** ** ****** room ** *** **** of*** ** **** ******.

**** ****** ****:

**** ********* ********* ** incidentally ******** ******* ******* of *** ******** ****** securing *** ******* ** the ****. *******, ** many *****, * **** deliberate ****** ** ****** for **** ********* ******** attaching * ********* **** to *** ******* *** rack ** *** ** a ****** ***. **** method ** ********* ** the ************ ************ ** the ****-******* ******, **** the *********** ******** *** mounting ************ ******** **** those *******. * ******* example **** * ********* switch ** ***** *****:

switch grounded to rackmount busbar

******* ******/*****: 

** ***** *****, * single ***** ** **** (often *****-***** *****) ** located ** *** ***** mount ** ******* ** a ******. ******* ******** for ******** **** ** in ********** ******** *****, or ******* *** ********* are ***** ******** ***** this ****** ** *****.  The '********* *****' ***** bonding ****** ** ****** wires *** ** ********** attached ** *** **** is ********* ****** **** a********* '****** *****' ******:

*** **** **** ** grounding ** ** ********, the ******** **** **** itself ** ******** ********* to * **** ** ground ***** ** *** other ***.

***** **** *****: 

*** **** ****** **** of ********* ******* ** also *** ***** ********* at ********** ************ ****** issues. ****** ********** ******* include * ***** ***** designed **** *** ******* plug *** ****** *********. The ***** ***** ***** how **** ***** ***** into ******* **** *** (green) ****** **** ******** to *** ****** **** inside *** ****:

*******, **** **** ** ground ***** ** ****** to ******** ****** ** the ******* ** ******** a **** ** ***** resistance ******* *** ******'* internal ***** ******, *** enclosure, *** *** **** electrical *******. *** ********* property ** **** **** of **** *** *** address *** ******* ** devices ** **** ********* to *** ****** ** a *******. ** ****, most ******** *** ***** supplies ******* ***** ******* of ********* ** ******** to * *****-******* ****.

****** **** *********: **** *** ********* and ******* ******* ** a ******** ****** ** grounded, ******** ***** ********* the ****** ****** *** typically ********* *** ** the ****** ** ************* ***** at *** ****** ** power ********* *********. **** the ***** ********** * camera ** ********, *** camera ** *********** ****** by *** ***** ** a ****** *****.

*********, *** ******* ****** of ***** ** ********** damage ** *** ****** side ** ********* ** lightning. ** ********* ******* near *** ******, *** cable *** ****** * conduit *** **** ********* extremely **** ********. * 'lightning ********' ** ********* used ** ******* *** surge ** ******* ** close ** *** ****** as ********.  

Cable ****** *********?
**** ********* ** ***** include ********* ** ******** grounding ******** ****** *** bundle. **** ******** *** (******** ******* ****)********* ******** * **** sheath **** ********* ***** or *** ****** ***** of ***** **** **** be ******** ** ********* potential ******* ********** ************. 

*** *** ******, **** shielding ** ******** ** be ******** ** *** ethernet **** ** *** switch. *******, *********** ********** contact **** *** ****** port *** *** *****'* shield ******** *** ********* itself ** ** **********. For *******, **** *** difference ******* *** '***' and '***' ***** *****:

*** '***' **** ** clad ** * ******** surround **** ***** *** cable ****** ** ******* with *** ******** ****. In ***** ** ******** the ******** ** *********, UTP ***** ********** ****** be **** ******** **** STP *******.

Ground-Loop ********

** ****** **** *******, when ******* *** ********* are ****** ** ****** with ********* **********, *** cable ********** ******* ***** two ****** *** ****** the **** *** ***** but ********** ******** ******** called '****** *****'. **** the ****** ********* ** analog **** ***** ******* being ********** ********* ** these ********,********* ** *********** ******** **** ** trap *** ****** ***** currents.

**** ** *****, **** is *** * ****** problem ****** *** ** the ******* **** ********** of *** *******. *** cabling ****** ***** ** much **** ********* *** such * ******* ** interfere *** ****** ** a '****' ** *****, and ********* ** *** a ********* *****.

Comments (10)

This is an defintely an under-appreciated topic. Thanks Brian!

Even non-hazardous currents can greatly disrupt the quality and transmission of electrical impulses, typical to ethernet traffic. To a lesser extent than safety, ground provides an outlet for these potentially disruptive currents.

Can you describe where these currents originate and how the grounding avoids the disruption?

I have been under the impression that grounding actually creates these currents by providing a path between ground differentials, as you say later.

Good article Ethan... it harkens back to my days designing mainframe systems. One thing we used a lot of was flat copper strips within the racks due to the extra low impedance they provide. This helped a lot with signal integrity between the units as well as a good path to earth ground.

With IP video, this is not a common problem simply due to the twisted pair properties of UTP cabling. The cabling design makes it much more difficult for such a current to interfere and travel in a 'loop' of cable, and therefore is not a practical issue.

Does this become more common again for those who use various EoC devices to propagate their IP signal thru coax instead of twisted?

Also, when, if ever, is it appropriate to 'float ground'?

Thanks!

Got Noise?

Start with AC power bricks.

Thank you for the article because grounding is almost always overlooked. I am looking for articles on this topic which describes in details but easy to understand how to design proper grounding against lighting strikes for CCTV system. I have few questions on this topic, sorry if they might seem to naive but I am not an electrician:

Can cable shield grounding be enough against lighting strikes to protect camera or does it always have to be lightning arrester used ?

Can we connect earth point of lightning arrester to cable shield grounding ?

If we have a camera on a pole and lightning arrester next to it - can the grounding cable from lightning arrester be placed along camera data cable and go to earth point of the building or does lightning arrester have to be earthed to the pole earth point (if exists) ?

B, we have a tutorial on Lightning Protection for Surveillance Cameras.

I will defer to Brian to answer your specific questions later this morning.

So one important point about Lightning Arresters: they do nothing to protect cameras, or whichever other devices they are connected inline outside a building. If lightning strikes your camera, it is toast. A lightning arrester primarily works to limit the harm of a lightning strike to only the camera.

It is kind of like a surge protector in reverse.

#1) "cable shield grounding be enough against lightning strikes to protect camera"

In general, no. Shielding is different than grounding, but there is really nothing that protects a camera from lightning. You can employ lightning rods (or some other more attractive conductor) that lightning may strike in lieu of cameras, but if lightning strikes your camera it almost certainly is a casualty.

#2) "Can we connect earth point of lightning arrester to cable shield grounding ?"

Again, shielding is different than grounding, but if we're discussing grounding like the article above mentions then yes, lightning arresters can be (and should be) connected to those points.

#3) "can the grounding cable from lightning arrester be placed along camera data cable and go to earth point of the building or does lightning arrester have to be earthed to the pole earth point (if exists) ?"

In general, the sooner you can ground a lightning arrestor, the better! I think either way you describe would work, but it sounds like physical distance to a ground point would be shorter at the pole.

Anytime a conductor carries hundreds of thousands to millions of volts (ie: a lightning strike) there is a high likelihood it will be obliterated in the process. Shorter ground paths = better because of less damage.

Great information, but I think it's also worth noting that most CCTV installers should not be dealing with grounding/bonding or lightning protection. That should be installed by qualified individuals who are trained for OSP cabling. Most people who attempt to do grounding or bonding end up doing more harm than good. (e.g. improperly grounding an IP camera connected to a network rack via shielded cable exposes defeats the grounding of the entire network.) It really is a specialty. When done improperly it is also a huge liability. The guy who does the grounding/bonding is typically responsible for the entire system and is often held responsible when disaster strikes.

Installing exterior cameras should really be done by OSP-trained individuals as well. In my state (Ohio) it's technically required, though rarely enforced--until something goes wrong.

I think you raise a good point that training is useful for 'doing it right', but I'll counter by saying subcontracting grounding out by security installers rarely, if ever, happens.  And items like pole mounted camera grounds or lightning arrestors simply would not be installed at all.

So the pragmatic solution is for security installers is to understand the need and importance of proper grounding.

With that considered, however, are you familiar with/ can you share examples of whole-system liability by a video installer if not done correctly?

In many cases, camera installers are tying in to existing grounding infrastructure, not greenfielding it new, so that's an interesting dynamic.

Yep, Mother Nature's strikes are best attracted to the path of least resistance.

Login to read this IPVM report.
Why do I need to log in?
IPVM conducts unique testing and research funded by member's payments enabling us to offer the most independent, accurate and in-depth information.

Related Reports

Assa Acquires LifeSafety Power on Sep 04, 2019
Assa Abloy is acquiring LifeSafety Power, adding to their growing collection of access control brands like Mercury, August, Pioneer Doors, and...
Register Now - October 2019 IP Networking Course on Aug 28, 2019
Register now for the Fall 2019 IP Networking Course. This is the only networking course designed specifically for video surveillance...
Mobile Access Control Guide on Aug 28, 2019
One of the biggest trends in access for the last few years has been the marriage of mobile phones and access cards. But how does this...
ZK Teco Atlas Access Control Tested on Aug 20, 2019
Who needs access specialists? China-based ZKTeco claims its newest access panel 'makes it very easy for anyone to learn and install access control...
Avigilon Blue VSaaS Tested on Aug 05, 2019
Avigilon says Blue is a "powerful integrator cloud service platform", easy to set up and configure, quickly scale business, by leveraging cloud...
HD Analog vs IP Guide on Jul 16, 2019
For years, HD resolution and single cable signal/power were IP camera advantages, with analog cameras limited to much lower resolution and...
Maglocks Usage Statistics 2019 on Jul 01, 2019
Maglocks divide access control specifiers perhaps more than any other component. Many are concerned about life safety codes, but others cite...
Hikvision ColorVu Camera Tested on Jun 24, 2019
Hikvision says their new ColorVu line captures "vivid chromatic images in darkness", with unconventional white light illuminations whereas most...
Risk of Amazon Alexa Guard: No Battery Or Cell Backup on Jun 20, 2019
Amazon positions its Alexa Guard Service as a "smart home security system" and says it can help you "keep your home safe". However, the...
ADT Eliminating Acquired Brands, Unifying Under 'Commercial' Brand on Jun 14, 2019
ADT is eliminating the brands of the many integrators it has acquired over the past few years, including Red Hawk, Aronson Security Group (ASG),...

Most Recent Industry Reports

How Cobalt Robotics May Disrupt Security on Sep 13, 2019
While security robots have largely become a joke over the last few years, one organization, Cobalt Robotics, has raised $50+ million from top US...
Panasonic 4K Camera Tested (WV-S2570L) on Sep 13, 2019
Panasonic has released their latest generation 4K dome, the WV-S2570L, claiming "Extreme image quality allows evidence to be captured even under...
ASIS GSX 2019 Show Report Final on Sep 12, 2019
IPVM went to Chicago for ASIS GSX 2019, with many exhibitors disappointed about traffic and the exhibitor schedule changing next year. Inside we...
Installation Course - Last Chance - Register Now on Sep 12, 2019
Last Chance - Register Now - September 2019 Video Surveillance Install Course. Thursday, September 12th is your last chance to register for the...
Commend ID5 Intercom Tested on Sep 12, 2019
Commend touts the new ID5 intercom as 'timelessly elegant' and the slim body, glass front touchscreen indeed looks better than common, but ugly,...
US State Department: "Chinese Tech Giants" "Tools of the Chinese Communist Party" on Sep 12, 2019
The US State Department has called out "Chinese tech giants" for being "tools of the Chinese Communist Party" in a blunt new speech that makes...
Uniview OEM Directory on Sep 11, 2019
This directory lists 20+ companies that OEM products from Uniview, with a graphic and links to company websites below. It does not cover all...
Yi Home Camera 3 AI Analytics Tested on Sep 10, 2019
Yi Technology is claiming "new AI features" in its $50 Home Camera 3 "eliminates 'false positives' caused by flying insects, small pets, or light...
Hanwha Announces 32MP Camera + AI Line on Sep 10, 2019
In the first rise in maximum megapixel resolution in 5 years, Hanwha has announced a 32MP / 8K camera directly competing with Avigilon's H4 30MP /...
Fingerprints for Access Control Guide on Sep 09, 2019
Users can lose badges, but they never misplace a finger, right? The most common biometric used in access are fingerprints, and it has become one...

The world's leading video surveillance information source, IPVM provides the best reporting, testing and training for 10,000+ members globally. Dedicated to independent and objective information, we uniquely refuse any and all advertisements, sponsorship and consulting from manufacturers.

About | FAQ | Contact