Electrical health of my installation

[Claudio Catanzaro 0]

Hi,

 

I had a home made 8 cameras installation with a dvr card. My card got fry, and the guys who sold it to me told me said that was for a faulty camera. One of my cameras was giving more tan 2 volts and a friend who help me to install them told me that he remember feel a electricity when he was adjusting focus for one of them.

 

Now I have bought a new card via Internet and I want to be sure that It will not be fryed too.

 

What do I need to check to be sure that my installation is fine?

 

Voltage? Impedance? Amperage? and how much of each one can a CCTV device afford without have some injure?

 

Thankyou for your answers

 

Claudio Catanzaro