Questions tagged [dielectric-breakdown]
Use this tag when the topic concerns a material which is designed to separate conductors is pushed beyond its voltage limits then allows current to flow. This can be in reference to capacitors or coax cable, among other things.
46 questions
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Can a capacitor fail in such a way that it causes a short DC short? [duplicate]
Under what conditions do capacitors fail as a short circuit instead of an open circuit? Additionally, what are the typical failure mechanisms associated with different capacitor types, and can any of ...
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FEM simulation of a high voltage composite dielectric configuration - interface charge and surface conductivity
I constructed a axisymmetric FEM model of two electrodes, one at 500 kV, held apart by a solid dielectric component immersed in SF6 gas.
I then extracted the information about tangential, normal E ...
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MOSFET Breakdown Voltage for this BMS circuit
I'm trying to design a BMS which has the following characteristics:
20 lithium-ion cells
in the discharging state, the cells are connected in series to develop a voltage of 84V max
in the charging ...
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What is the breakdown voltage of air (actually)?
Everyone knows that the breakdown of pure, dust-free, dry air is around 32kV per cm. Despite doing a lot of research I can't seem to find even a range of values for ordinary air that consistently ...
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Spark gap breakdown voltage vs gap area
I've been trying to design a 1 MV hydrogen gas spark gap.
I found the resistance of such to be in the range of 7 Ω/cm, not suitable for a target 40 kA current. Can I make the spark gap shorter without ...
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Why is there a gate-source short on a PMOSFET (DCDC circuit attached)
I am a beginner in power supply units. I got a failed DCDC regulator board and confirmed a gate - source short in a PMOSFET (about 2 ohms in both directions). As far as I know, this board is a power ...
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Effective dielectric constant in multilayer PCB design
Top => copper
PP1 => RO4350B
L2 => copper
PP2 => FR4
L3 => copper
PP3 => 185HR
L4 => copper
This is my PCB stackup.
In the top layer, I have a 50 Ω controlled RF trace. The ...
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Hipot results vs surface area
I trying to hipot test a 12"x12" metal with kapton layer. Different sizes of metal (e.g. 1"x1", 4"x4", banana plug) is placed on top of kapton tape. The bigger metal ...
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Why are the voltage ratings of switch contacts so much lower than breakdown voltage?
I need a switch for a high voltage application, say 5 kV, and I'm looking at relays. From a breakdown voltage standpoint, a contact with a 5 mm gap should be able to withstand 15 kV, which is 3x what ...
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Spark gap minimum breakdown voltage vs air gap
I'm trying to calculate the minimum voltage needed create a spark across 2 electrodes (needle shaped) in open air at normal ambient pressure.
Usually, I would use the figure of 3000V /mm as the ...
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Dielectric strength withstand vs impulse withstand
In ISO 6469-3 two tests are defined.
Dielectric strength test: Extended period of time (1min) at a set voltage over insulation barriers (simplified). Usually a ramp up of the voltage is allowed.
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Transformer checking after flood
We have isolation transformers used in our noise test room. Basically, the just provide isolation so that during noise tests, the noise waveforms (impulse, surge spikes) from the tester is isolated ...
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How can fumes make this electrical arc travel so far in distance to the other side?
Why is the arc travelling so far, and what kind of vapor conducts electrons so well?
https://www.youtube.com/watch?v=PXiOQCRiSp0
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What is the best way to transmit 1 kW (power supply) to a tethered drone so that the cable thickness and weight is minimized?
I am delivering 1 kW power to a tethered drone. To minimize the wire weight and maximize maneuverability, I would like to keep the wire as thin and lightweight as possible.
The motors on my drone have ...
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Insulation safety ratings (working and withstand voltage) of fiber optics cables
I'm trying to build a high voltage optocoupler to implement galvanic isolation between a high voltage supply and its control signals. Since the working voltage is several kilovolts, it's beyond the ...
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