Black lines with dahua nvr 8 cameras 12v psu

[alexistkd 0]

Hi, i have just installed in my house 8 cameras, im getting blacklines and some interference using a 8ch dahua dvr with 8 12v cameras all of them have IR.

 

i currently use this psu:

 

9 Way/Port 10 Amp 12V CCTV PSU

 

all my cameras are conected there i use for positive blue/green wires and for negative white green/ white blue

 

i connect the PSU to my UPS APC

 

here i attached a image showing the black lines: http://imgur.com/a/JHcEW

 

Its strange that when i just connect one camera to the PSU it works good i see no interference right away after i connect the second one then i see interference and black lines.

[tomcctv 190]

Hi. Can you also give length of cable for each and type of baluns used