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 ** *** ********.

** **** ****, ** explain *** *** ******** involved *********:

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

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

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

********* *** ******* **** electricity ******* *** **** of ***** **********, ********* and ******* ** *** practice ** ********** ************ sensitive ********* ** ** engineered *****

  • ********* (**** ****** ********): ********** ********** ********* 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 ********** **** ***** to ****-******* ******* **** apply ** ***-******* ****.
  • ****** *********: **** ** ******** 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 *********:

  • ***-*** [**** ** ****** available]: ** ********** ****** 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 * *** ** TMGB ****** [**** ** longer *********].

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

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

******* ******/*****:

** ***** *****, * 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 ****** ** ************* being ** *** ****** or ***** ********* *********. When *** ***** ********** a ****** ** ********, the ****** ** *********** bonded ** *** ***** to * ****** *****.

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

Cable ****** *********?Some varieties of cable include shielding or metallic grounding elements within the bundle. Most commonly *** (******** ******* ****)********* ******** * **** 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 ********, ********* ** blockers [**** ** ****** available] *** ******** **** to **** *** ****** those ********.

**** ** *****, **** 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.

Read this IPVM report for free.

This article is part of IPVM's 6,367 reports, 855 tests and is only available to members. To get a one-time preview of our work, enter your work email to access the full article.

Already a member? Login here | Join now

Related Reports

BICSI For IP Video Surveillance Guide on Feb 11, 2020
Spend enough time around networks and eventually someone will mention BICSI, the oft-referenced but only vaguely known standards body prevalent in...
Access Credential Form Factor Tutorial on Feb 10, 2020
Deciding which access control credential to use and distribute, including form factor, can be a difficult task. Knowing the limitations and...
Fail Safe vs. Fail Secure Tutorial on Oct 02, 2019
Few terms carry greater importance in access control than 'fail safe' and 'fail secure'. Access control professionals must know how these...
Cable Firestopping Installation Guide on Mar 06, 2019
Installing cables through firewalls is a critical installation issue. Failing to properly seal a penetration can cause smoke and fire to spread,...
Drain Wire For Access Control Reader Tutorial on Sep 04, 2018
An easy-to-miss cabling specification plays a key role in access control, yet it is commonly ignored. The drain wire offers protection for readers...
Exit Devices For Access Control Tutorial on Aug 28, 2018
Exit Devices, also called 'Panic Bars' or 'Crash Bars' are required by safety codes the world over, and become integral parts of electronic access...
'As-Built' Drawings Tutorial on Mar 20, 2018
Closeout documentation can be invaluable for future expansions or maintenance work, and 'as-built' drawings are a key aspect for finishing projects...
Genetec Launches Community Connect Examined on Sep 14, 2017
Genetec has done best in large-scale, enterprise systems and relatively worse in smaller systems such as SMB. Now, Genetec is launching...
Alarm Circuits Guide on May 09, 2017
Alarm circuits are a fundamental element of wired burglar systems. Designing the alarm circuit greatly affects its performance. In particular, more...

Most Recent Industry Reports

Hikvision Illicitly Uses Back To The Future In Marketing on Jul 03, 2020
NBCUniversal told IPVM that Hikvision UK's ongoing coronavirus marketing campaign using NBCUniversal's assets was not allowed. Hikvision mass...
Verkada: "IPVM Should Never Be Your Source of News" on Jul 02, 2020
Verkada was unhappy with IPVM's recent coverage declaring that reading IPVM is 'not a good look' and that 'IPVM should never be your source of...
Vintra Presents FulcrumAI Face Recognition on Jul 02, 2020
Vintra presented its FulcrumAI face recognition and mask detection offering at the May 2020 IPVM Startups show. Inside this report: A...
Uniview Wrist Temperature Reader Tested on Jul 02, 2020
Uniview is promoting measuring wrist temperatures whereas most others are just offering forehead or inner canthus measurements. But how well does...
Dahua USA Admits Thermal Solutions "Qualify As Medical Devices" on Jul 02, 2020
Dahua USA has issued a press release admitting a controversial point in the industry but an obvious one to the US FDA, that the thermal temperature...
Access Control Online Show - July 2020 - With 40+ Manufacturers - Register Now on Jul 01, 2020
IPVM is excited to announce our July 2020 Access Control Show. With 40+ companies presenting across 4 days, this is a unique opportunity to hear...
Hanwha Face Mask Detection Tested on Jul 01, 2020
Face mask detection or, more specifically lack-of-face-mask detection, is an expanding offering in the midst of coronavirus. Hanwha in partnership...
UK Government Says Fever Cameras "Unsuitable" on Jul 01, 2020
The UK government's medical device regulator, MHRA, told IPVM that fever-seeking thermal cameras are "unsuitable for this purpose" and recommends...
Camera Course Summer 2020 on Jun 30, 2020
This is the only independent surveillance camera course, based on in-depth product and technology testing. Lots of manufacturer training...
Worst Over But Integrators Still Dealing With Coronavirus Problems (June Statistics) on Jun 30, 2020
While numbers of integrators very impacted by Coronavirus continue to drop, most are still moderately dealing with the pandemic's problems, June...