Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [ratings]

90 questions
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Is C0G a synonym for NP0?

This question is in the context of a production environment where part numbers and change notices are strictly controlled, and any alternate manufacturer parts under an internal part number must be equivalent components. For Class 2 Dielectrics,…
crasic
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Can I swap an electrolytic capacitor with one with a higher voltage?

I wish I knew more about this stuff, but alas I do not. I have a radial lead aluminum electrolytic capacitor (rated 470mF and 25v) that died on me. Can I swap it out with one rated at 35V, or do I need to get one matching it completely? It is for…
Dan Appleyard
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Voltage rating vs. power rating of a resistor

My question may sound very basic, but I am very confused by the difference between the voltage and power ratings of a resistor. Vishay's document says: Rated Power The maximum amount of power that can be continuously loaded to a resistor at a…
Angs
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Technical explanation desired: are TVS safe for continuous dissipation? Why/why not?

In answers such as this one, https://electronics.stackexchange.com/a/647135/311631 I've seen suggestions that TVS diodes are not "reliable" under repetitive or continuous operation, such as a Zener diode might be used. (Assume the poorer tolerance…
Tim Williams
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Why can't a power supply supply low current?

I've just read this article and don't quite understand how a power supply can't supply such a low current. I was always under the impression a power supply could supply anything up to its rating, but didn't have a lower limit. So why would they need…
Dean
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µ in the Middle of a Capacitor Rating

I'm looking at an electrolytic capacitor (and old blue, Philips one used in electronics classes) and am wondering why it is printed with 4µ7-M. I tried Googling, figuring that it was a common enough occurrence, but found nothing. Is that supposed to…
Synetech
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Current and Voltage Ratings for Multi-Conductor Connectors

I am currently looking at some multi-conductor connectors that will handle reasonably high currents (approximately 30 A at 24 v). When reading datasheets, I see that the connectors have both a maximum current and a maximum voltage. For…
Michael Koval
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Selecting the right bridge rectifier

There are a number of schematics I'm trying to interpret that have bridge rectifiers. In the components list, however, they're simply listed as "D1-D4 rectifier unit" without any specific values. How do I interpret the specific rectifier parameters?…
dwwilson66
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Difference between [W] and [WS] power rating of resistors

I see some datasheets of power resistors where power ratings are in Watts [W] and some in [WS] which I don't know what they mean. What is the difference between them? Example of datasheet Some screenshots from datasheets:
Chupacabras
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How can I test battery for true mAh rating?

Is there a way I can test the capacity of a 3.7v rechargable lion battery like this at home? All I really have is a multimeter. (Image source)
TheMidnightNarwhal
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Verifying supercapacitor capacity

I have procured some supercaps. No datasheet was provided. The only data I have is what is printed on the caps themselves: "4.0F 5.5V cda®" Since my DMMs don't measure capacitance in Farads, I setup the following circuit shown below. Two "10Ω 1% 2W"…
Bort
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Selecting voltage rating for capacitors

In my project I want to use some ceramic and electrolytic capacitors, I will need the capacitors be at least 10V rated, but what will happen if I use much higher rated capacitors (just to make sure in case of something went bad they don't explode!)?
Dumbo
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Power Mosfet Gate Voltage

The early Power Mosfets were deemed to be fully enhanced with 10 VDC between gate and source. The gate source threshold voltage was defined for 1mA drain current and would be between 2 and 4 VDC. The gate source rating was 20VDC but the curves…
Autistic
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Vacuum cleaner power rating does not match line voltage and current rating

I have a vacuum cleaner on which is proudly written: 12.0 Amps 1300 W Assuming a 120 V (RMS) power supply, how would the power consumption of the vacuum cleaner be calculated given the 12.0 A current draw? It seems that \$120 \mathrm{\,V}\cdot12…
Doubt
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How are switch ratings determined?

As the only functionality of a switch is to interrupt the flow of electricity, it acts like a small resistor right? Lets say that we have a switch that its max ratings are 3A/250V AC. So if we connect it directly to source it will handle up to 3 A *…
matthewg
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