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Power supply ground loop. 3 Prong to 2 prong cable.

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I recently purchased a dedicated power supply from amazon.

http://www.amazon.com/gp/product/B002OXL8IY/ref=oh_o04_s00_i00_details

VideoSecu 18 Output 12 V DC CCTV Distributed Power Supply Box.

 

This introduced a ground loop in my system.

I solved it by purchasing a 3 Prong to 2 prong grounding converter and connecting the 3 prong power cable from the power supply to the UPS without the grounding.

Is it OK to use it without ground or I should eliminate the ground somewhere else?

 

This is my configuration:

a Q-See DVR with 8 cameras. 7 cameras are connected using their default cheap q-see cables (which is ok), one camera is connected over cat6.

The cameras came with two wall adapters (wall charger type) split in 4 each. Those had only two prongs, no ground.

A 42" TV is connected to the DVR over a 25 ft long SVGA cable.

I started seeing white lines across the screen when I started using the new power supply.

No ground loop if using only the camera connected over cat6 to the new power supply. Any of the cameras connected using the original cable will cause a ground loop (not very strong). I think this is doe to the cable using the same ground for power and video signal. (with cat6 I use separate pairs).

 

I guess that replacing all the cables with cat5 will solve the problem too, but that is too much of a trouble.

 

The question is: What "side effects" can I get by converting the 3 prong cable of the new power supply to 2 prong. What is the right way to fix my ground loop problem?

The power supply is connected to an APC UPS, the ups is connected to a GFCI outlet. The DVR is connected to the same UPS. The TV is in another room connected to a different power outlet.

 

Thanks.

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thanks.

 

Actually what I have done, however, is disable an important safety feature that protects me from electric shock if a wire inside PS comes loose.

I will just unplug the PS box when I need to work inside it, or remove the 3 to 2 adapter.

 

Probably at one point I will switch to using cat5/6 cables to each camera anyway.

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Given that a number of power cans of this type come with only two-prong cords in the first place, I don't think you have much to worry about - the high voltages are all contained within the switching unit in that thing anyway.

 

Unplugging it might be a good idea when working inside it anyway, grounded or not.

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