Questions tagged [electrolytic-capacitor]
An energy-dense polarized capacitor type, used in low-frequency filtering applications.
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What would be the cause of measuring AC voltage across a LM7805?
This is my first time here so I apologize if I don't provide enough information. I am trying to repair a centrifuge that is giving an error on its LCD display. Though the service manual doesn't say ...
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Question about series-connected (pseudo-nonpolar) electrolytics
Another Q&A on this site ("Ceramic caps vs electrolytic. What are the tangible differences in use?") contains good information on capacitors in general, including parameters I wasn't ...
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Aluminum Electrolytic Capacitor submersed in synthetic (PAO) oil
We are testing solar water pumps which have the 3phase inverter for the BLDC in the down hole pump. The boards (one power board, one controller board) are submersed in the lubricant oil that is used ...
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Replace filtering(?) capacitor on CRT deflection Board
I am doing partial recap on CRT monitor Sony PVM 20m2e. (monitor was working, but RGB lines at the top of screen which should be hidden were visible and geometry is not top notch)
I desoldered C584 ...
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Where to place a cooling fan supply capacitor
I want to run a ~2W, 12 VDC fan in an EMI-sensitive environment.
The schematic is shown below. Due to the spiky current draw, I intend to place C1 and C2 right by the fan connector, so high frequency ...
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How can I measure the voltage of a capacitor using multimeter?
I'm new to electronic and trying to measure a capacitor (Aluminum Electrolytic one) using a multimeter. The cap is already charged. What I did is to touch the positive leg of the cap with the red ...
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How to visually distinguish metal film and ceramic capacitors (leaded)?
This question only involves the leaded components.
Electrolytic capacitors are each to recognize since they are usually in cylindrical cans. However, I am not sure about distinguishing the other two ...
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Tantalum capacitor at low temperatures
What could happen to a solid tantalum capacitor that operates below the lower temperature range defined by the manufacturer (-55°C)?
From my understanding, there would be a performance issue with ...
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Discolored negative lead on electrolytic capacitors
Would the discoloration around the negative lead of these capacitors be a sign of failure? If so, why would the negative lead darken instead of the positive - or both leads.
They are Maron EFM 35 ...
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How to Determine Input Capacitor Value for Peak Power Requirement
For flyback SMPS, how do we know that our input capacitor value is sufficient for some peak power requirement?
I understand that bigger input capacitor will have more advantage on this peak power. ...
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1V Overshoot and Undershoot on Power Rails of LTE Module
I have designed a PCB (four layer) having SIM7600I LTE Module. The Stackup is:
Signal & Component Layer with Ground Pour
Internal Ground Power Plane
Internal ...
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Decipher Surface Mount Aluminum Electrolytic Capacitor Markings
I am repairing a Definitive Technology BP-7004 Super Tower's power supply / amplifier that makes a buzzing noise when it is cold. After it warms up, the buzzing slowly fades away. I've attached an ...
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How can I improve conducted emission caused by a bad primary electrolytic capacitor?
I recently got the job to find out how to pass conducted EMI tests with a bad electrolytic capacitor after the rectifier in a power supply. The background is of course, that the new type is cheaper ...
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Multiple smaller capacitors on power rail for NeoPixel / WS2812B strip
I read in the AdaFruit guide that a 500-1000uF capacitor is recommended on the power rail.
However, electrolytic capacitors in this capacitance are quite large. Depending on the length of the strip, ...
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Cyclic Voltammetry for a Capacitor - Positive Current, Potential is decreasing?
In the boxed red region, why is the potential decreasing when the current is still positive? To my understanding, when the current is still positive (i.e. not changing direction), the capacitor will ...
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