hazim 0 Posted May 1, 2014 Dear, I have a problem in a CCTV system when some electric shock or electromagnetic effect had damaged 3 cameras and 3 inputs of a DVR. The three cameras are connected to the DVR via UTP cable with video baluns. The cameras have several burnt components in the board so I will replace the boards. The DVR have the 3 port's 75 Ohm resistors burnt out but also another paralleled component with these 3 resistors named as S as the resistor is named as R and capacitor as C...etc... so what is the "S" component? some suppression component? with what should I replace it? The attached image clarify the components. Regards, Hazim Share this post Link to post Share on other sites
ssnapier 0 Posted May 2, 2014 It could be a diode, but typically "S" stands for switch on a board. Share this post Link to post Share on other sites
hazim 0 Posted May 2, 2014 Ofcourse it's clear these are not switchs, but also I don't think they will name the diode with "S", and there is no polarity also (anode-cathode). Also, there is no meaning for the diode there. I think this is some component that works as varistor but for low AC voltage. Share this post Link to post Share on other sites
hazim 0 Posted May 3, 2014 Yes it seems some supressor component, as I found Z-shape symbol under it. Anyway, this is a protection item against high voltage such as varistor as I expect. I replaced the 75 Ohm resistors but the DVR defected inputs didn't worked. There would be damaged IC's. Better to replace the DVR. Share this post Link to post Share on other sites
