Adding cameras to my system???

[danyorks 0]

I am a complete newbie...

 

I purchased and installed a Swann NVR8-7085 HD 8 channel 720p 1TB NVR with 4 x NHD-806 cameras CCTV Kit

And I have to admit I am very impressed (never had anything to do with cctv before)

 

As there is room for 4 x more cameras I purchased 2 x Security 720P H.264 1.0 MP HD Cloud ONVIF 2.0 IP P2P IR 24 LEDS IR Dome Camera (off ebay)

 

I assumed they would just be plug & play like the ones that came with the kit but NO, when I plug them in - nothing.

 

Obviously I have no real idea what I'm doing - can anyone help?

 

Thanks...