Camera grounding question

[tomcctv 190]

its very clear in the manual what to do with the ground wire.

 

1. leave at camera end (not connected)

2. extend to Recorder location and incorperate into push button for camera hard reset.

 

 

 

NOT a ground

 

 

put it another way. avtech did not build a hard reset into the camera .... so instead of re-designing the case they have added external fix. (ground to live) for hard reset)

[westom 0]

avtech did not build a hard reset into the camera .... so instead of re-designing the case they have added external fix.

Why would they do that when POR (Power On Restart) is a standard function inside all electronics? Power cycle does the hard reset.

 

It's a rhetorcial question.

[tomcctv 190]

avtech did not build a hard reset into the camera .... so instead of re-designing the case they have added external fix.

Why would they do that when POR (Power On Restart) is a standard function inside all electronics? Power cycle does the hard reset.

 

It's a rhetorcial question.

 

 

 

every time you have say a power cut you dont want to have to keep programing camera. so stores info...... you need a hard reset for lost passwords or camera relocate.

 

 

and also with alot of Taiwanese manuals ground means neutral. which looks like is the problem of this post.

[bud--- 0]

Don't connect to or even touch AC service. Ground connects to a safety ground bus bar inside the breaker box.

Opening the panel and connecting to the neutral/ground bar is 'connecting to the AC service'.

 

The code is quite clear in Article 250.53(D)(1):

A metal underground water pipe shall be supplemented by an additional electrode of the type specified in 250.52(A)(2) through (A)(7).

From the National Electrical Code Handbook - published by the NFPA (which also publishes the NEC.

"The requirement to supplement the metal water pipe is based on the practice of using plastic pipe for replacement when the original metal water pipe fails. This leaves the system without a grounding electrode unless a supplementary electrode is provided.”

 

The only ground that cannot exist alone is a water pipe ground.

There are only 3 grounding electrodes that are always required (if present) to be used to ground a service. Water pipes (minimum 10 feet of metal in the earth) are the only electrode that are likely to be in a house. Water pipes are REQUIRED to be used as an grounding electrode, just as they have since time began. Connections currently have to be within 5 feet of where the pipe enters the house.

 

Metal municipal water pipe systems typically have a resistance to earth of 5 ohms or less. Ground rods are only required to have a resistance to earth of 25 ohms, or you can use 2 rods and there is not requirement. Two rods were typically installed. Ground rods are a crappy electrode. For new construction with footings or foundations a "concrete encased electrode" is usually also required. It is a good electrode, and is used instead of ground rods as a "supplementary" electrode.

 

You were asking about protection of a camera and DVR. Both current codes and electronics protection require that $20 of grounding parts installed.

Nonsense.

 

BTW, 16 AWG wire is too small for lightning protection. Use 12 AWG to earth the camera.

BTW protecting the camera from a direct lightning strike involves far more than #12 wire. There is other particular current source from lightning for the camera mounted on wood.

 

A dedicated ground rod for the camera, in another westom post is stupid. The earth potential the rod can be far different from the power system earthing system during a strong surge event or a very near lightning strike. Resulting high voltage can show up at the DVR between power and camera wiring. It is also a NEC violation.

 

Excellent information on surges and surge protection is at:

http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf

- "How to protect your house and its contents from lightning: IEEE guide for surge protection of equipment connected to AC power and communication circuits" published by the IEEE in 2005 (the IEEE is a major organization of electrical and electronic engineers).

And also:

http://www.eeel.nist.gov/817/pubs/spd-anthology/files/Surges%20happen!.pdf

- "NIST recommended practice guide: Surges Happen!: how to protect the appliances in your home" published by the US National Institute of Standards and Technology in 2001

 

The IEEE surge guide is aimed at people with some technical background.

 

When using a plug-in protector all interconnected equipment needs to be connected to the same protector. External connections also should go through the protector.

 

I would connect camera power supplies at the DVR protector, if you are using one. But wallwart supplies tend to not be a surge problem. I would avoid other connections to grounds - during a surge event they may be at a high voltage with respect to the DVR. I agree with almost everyone that this is being overthought.