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I have a circuit I need to find a voltage on. Is there a way to figure it out on the provided picture in here?
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Typically, you apply a known source voltage. Apparently not in your case, so you'd better explain what this circuit applies to.1) I want to find out the source voltage.
Yes, the voltages across both parallel branches will be related to the voltage coming from the source. You can work backwards to solve for the source voltage. Note that the maximum voltage across any individual parallel branch does not necessarily correspond to the maximum voltage from the source at the same time. You have reactive components, so you will have phase differences.hmm...
How about knowing the max voltage that will be accross both parallel branches seperatly? Would that give me enough knowledge to then find the source voltage?
This isnt exactly a circuit equation. I am actually trying to find breakdown voltages across multiple layers of materials and I came accross an article that had this as a way to solve it but it didnt go into much detail about solving it.
Then your voltage source is 34 kVOk well the first branch has a voltage of 30 kV and the second branch has a voltage of 4 kV.
Yes, but you could be omitting information if you are not so sure what is going on and where you got the 30kV and 4kV numbers.Its really just adding the 2 voltages together?
Dielectric strength just says what voltage is needed to breakdown the dielectric. It can't be used for circuit analysis unless you have more information.I got the 30 and 4 from the dielectric strength of the materials. The dielectric strength of the dielectric layer is 30 kV/mm and it is going through 1 mm and the air gap is 4 mm and the dielectric strength of air is about 1 kV
What is the purpose of the voltage divider and two different dielectrics? Are you trying to compare one to another?hmm... well im trying to find what voltage it should take to break through multiple materials so I am unsure what the final voltage should be. from my initial testing i am getting 3338 kV. I am just trying to find a way to calculate it to verify my results.
Hmmmm.....I don't think you are looking at things correctly.hmm... well im trying to find what voltage it should take to break through multiple materials so I am unsure what the final voltage should be. from my initial testing i am getting 3338 kV. I am just trying to find a way to calculate it to verify my results.
Well I can do that and I have been doing that. I just want to see if I can verify my results with Math since I am being told that the numbers I am getting seem to be a bit high.What is the purpose of the voltage divider and two different dielectrics? Are you trying to compare one to another?
If you just want to test what voltage it takes to break through the materials, can't you just place the materials in series with a variable voltage source and increase it til they break down and write down that voltage?
We are trying to test our parts dielectric strength and we need to have an air gap so we can use less tooling so we dont have to have a different test fixture for every part.Hmmmm.....I don't think you are looking at things correctly.
Incidentally.....why do you want to find the voltage across the loads? Why does that interest you? If you tell us why you are interested in voltage across load....that might help us solve your question.
Your breakdown tests appear to be spot on. If the dielectric were rated with a breakdown of 30kV then you'd expect this to be conservative, so finding it can reliably withstand at least 33kV would confirm this.hmm... well im trying to find what voltage it should take to break through multiple materials so I am unsure what the final voltage should be. from my initial testing i am getting 3338 kV. I am just trying to find a way to calculate it to verify my results.
Do you have any idea what this means?We are trying to test our parts dielectric strength and we need to have an air gap so we can use less tooling so we dont have to have a different test fixture for every part.
Won't the air gap have some resistance at this point when it is ionized, rather than acting strictly like a short?Your breakdown tests appear to be spot on. If the dielectric were rated with a breakdown of 30kV then you'd expect this to be conservative, so finding it can reliably withstand at least 33kV would confirm this.
Examining your RC model at 50Hz, we can overlook the presence of both resistances because they have little effect in comparison with capacitances of the values you give. Your air gap capacitance is so much smaller than the dielectric capacitance, that the air gap will carry 98% of the applied voltage until the air breaks down and conducts. This will occur at around 4kV.
For applied voltages greater than 4kV the air gap is effectively conducting, leaving all of the applied voltage impressed across your dielectric. With your dielectric's rated breakdown strength of 30kV then for applied voltages exceeding 30kV you will find the dielectric is subject to breaking down.
https://www.physicsforums.com/images/icons/icon2.gif [Broken] Essentially, the air gap is not interfering with your voltage tests.
When the applied voltage is removed, the air gap capacitor repairs itself; alas, the plastic dielectric does not.