Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Imported Low Frequency Transient Susceptibility Power Lines calculation

Winsu

Full Member level 3
Joined
Oct 25, 2017
Messages
159
Helped
2
Reputation
4
Reaction score
3
Trophy points
18
Activity points
1,540
Hi All,

Happy new year all.

I want to calculate the amount of energy MOV or TVS needs to dissipate when they are going to experience a transient.

There a low transient test for the Def Stan 59-411 that specifies the following:

1609688242856.png

1609688313256.png


That basically means that if the EUT has a nominal input of for example 24V, the test will inject 600 V+/- 10% at a frequency of 15.9Khz.

1609688417107.png


I need to calculate how long takes half period of time of 15.9khz to calculate the energy dissipated ( 16khz to make it easier).

T= 1/2* f -> 31.25us.

Once I have the shape of the curve ( lets assume it is sinusoidal), the peak voltage and the how long take half period of the signal, how can I calculate the energy that needs to be dissipated to protect the product?

Can I assume the RMS value of the 600V peak which is 424V ?. Then if the max current supply by the source is 600V/10ohm = 60A

Can I say that the device has to dissipate P = V* I * T = 424V * 60A * 31.25us = 0.795w?

If my calculations are correct, how can I compare it with the MOV chosen to know if it would absorb the energy or no?

Below is the table of the MOV chosen. The second last column indicates that wattage maximum in two seconds....., how I do compare my results to verify that MOV would resist the energy.

1609690335309.png


I may mixing concepts or missing some relevant information, if you could please give a hand that would be very helpful, thanks
 

Attachments

  • 1609689839393.png
    1609689839393.png
    34.9 KB · Views: 26

LaTeX Commands Quick-Menu:

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top