All Questions
Tagged with fault short-circuit
15 questions
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SLG Fault calculation at Bus 3 (33kV) for three winding transformer- see image below
Can someone please help with solving Single Line to Ground fault current at the Bus3 of the below single line diagram, single line parameters are as below:
Grid:
3Ph Fault current 50kA, X/R =14
1Ph ...
- 1
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0
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88
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How to calculate short circuit current contribution of a PV plant into network?
I want to calculate the short circuit current contribution of my PV plant. I have only data from the inverter manufacturer but I am not sure if I have to simply add up all the inverter's short circuit ...
- 37
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2
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3k
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Sparking when using multimeter
I was trying to measure the voltage across two connectors that connect to a 3-pin, 13 A plug as part of troubleshooting, to verify I had circa 230 VAC present.
However, when I connected my multimeter ...
- 313
1
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1
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101
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Is the same overcurrent relay used for both phase-to-phase faults and 3-phase faults?
In MV grid with no distributed generators, 50-51 overcurrent relays are used to detect both phase to phase faults anf 3-phase faults.
In Italy, time independent characteristics are used inside these ...
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1
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1k
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Why is the line-neutral fault current 1.5x higher than the line-line fault current?
My commercial wiring textbook and several documents discussing fault current calculations stated "The L-N fault current is higher than the L-L fault current at the secondary terminals of a single-...
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1
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Is the impedance bus matrix method the same as the Ohmic method in power system fault analysis?
There are a few methods to do power system fault analysis, like the per-unit method, MVA method, and impedance method (Ohmic method.)
I am doing fault analysis using per unit symmetrical component ...
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1
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1k
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What is the fault level of paralleled transformers? [closed]
When paralleling transformers the fault level at the bus is it the sum of the individual transformer fault level?
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1
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1k
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How can there be a zero sequence current in a single line to ground fault with an ungrounded neutral
The circuit that describes a single line to ground fault in a system with an ungrounded neutral is:
I neglect capacitance between phases and only look at capacitance to ground.
The definition of zero ...
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1
answer
228
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What's the use of the ground socket of an ungrounded GFCI receptacle?
Is the ground socket of a GFCI receptacle that isn’t connected to ground useful? (I'm in the United States, if it matters.) If the connected appliance had current on its ground pin, where would this ...
- 259
2
votes
3
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4k
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Can hair short an electrical circuit?
Taking this as an example - if a strand of hair gets in say in cpu socket of a PC or any other slot of device, what would be the consequences, rather the symptoms if the hair gets in between those ...
- 29
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1
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535
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Three phase short circuit and line to ground short circuit
Why is three phase short circuit calculated current higher than line to ground or (phase to ground) short circuit calculated current in most cases?
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1
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2k
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What determines what type of short-circuit current is highest?
I'm doing a short-circuit analysis of a system, and started wondering about the following: What determines which type of fault current is the highest (and lowest)?
The screenshot below shows the ...
- 1,619
4
votes
1
answer
2k
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How can I identify the fault on an Arduino Uno board that's had the smoke let out?
I recently purchased an Arduino Uno. I've been having a ton of fun fiddling with it -- that is until I pushed +12V to the Vin without any kind of voltage step-down. The smoke was violently released ...
- 213
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0
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144
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Faulted phase detection
Currently I am studying about short circuit detection on long lines and I can't solve one task:
I have line between two substations, and there is short circuit some where on this line. I know current ...
- 55
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3
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35k
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What can cause a Drain-Source short in a FET?
Background:
I am using a Si7456CDP N-channel MOSFET in a switching power supply. The power supply and load are housed in a plastic enclosure. Yesterday, the power supply and load were working ...
- 27.6k