For long time I have been looking for a source for this but I dont know how to articulate it. Sometimes I need to send analog signal or DC voltage for hundreds of meters by using STP cables. But the projects sometimes outdoors where it is on the top of a bridge where lightings or other phenomena might cause interference on the transmission lines.

I juts need to know if there is any way I can investigate what in industry or in practice used as method as protection for possible high transients.

So below is an example where a 12VDC supply voltage is sent to a far end electronics which has no protection and can be a electrolytic capacitor followed by a voltage regulator:

enter image description here

I marked the nodes as A B C and D. How could the type of the component be figured and the location considering the above scenario? For instance would placing TVS diodes across A B and C D be a way to protect both sides frrom possible high voltage spikes?


All protection circuits need a voltage-divider action, thus both a series impedance and a shunt impedance. The TVS diodes are the shunt.

Often the only series impedance is the WIRE INDUCTANCE.

You can improve the protection by adding series impedance: resistors and/or inductance.

Here is how I've suppressed serious trash: 2 series inductors and 1 parallel capacitor, used 3 times


simulate this circuit – Schematic created using CircuitLab


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.