Questions tagged [ac]
AC stands for Alternating Current. It usually applies to voltages with >100 V RMS, but can also be used for other AC voltages, like 24 V industrial AC power.
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What is the correct formula for the 3 dB frequency of an RC or LC Circuit?
Before we jump to another post where the formula is
I am reading through the text book Microelectronic Circuits 8th edition by SEDRA/SMITH. In the text, they show this table.
Here it shows the time ...
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3-Phase system Voltage conversion
If we are converting from Y to delta configuration or vice-versa, how do we convert the phases of our voltages? I've seen that we need to add or subtract 30 degrees from one another, but I don't ...
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What is the role for each of these AC coupling components?
I'd like to learn more about the RP2040 PWM Audio AC coupling circuit found in figure 22 in this document.
Figure 22. Schematic section showing the Analogue PWM audio circuit
Even though I understand ...
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Non contact AC voltage detector circuit current calculation
This seems to be a common circuit for a non-contact AC voltage detector:
Non-Contact AC Line Detector using BC547
The probe generates a small amount of current when it is near an AC line due to ...
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How is the reactance of a capacitor formulated?
Question: Understanding the Reactance of a Capacitor
Hi everyone,
I'm having trouble formulating the reactance in a capacitor and would appreciate some help. Here's what I understand so far:
We have ...
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Are there any regulations that disallow simple AC-to-AC mains to low voltage power supplies? [closed]
I have found that it's quite hard to find AC-to-AC adapters that convert mains AC to a low voltage AC. Usually most devices use AC-to-DC adapters for understandable reasons: electronics don't run on ...
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Contactless AC line detection using a single transistor
I have seen circuits that are used to detect the presence of AC voltage without any contact, like the one below.
Non-Contact AC Line Detector using BC547
I have tested this circuit and it works fine.
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I'm trying to wire this motor I have, but I'm not sure how to read this diagram
This motor is 110V or 220V. I'm trying to wire it up for 110 but I'm not 100% sure how. Is low std 110V and high 220V?
I believe I need to connect 1,3,8 to hot and 2,4,5 to neutral and ground to the ...
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Potentiometer for Kitchen Fan
I'm exploring the possibility of building a potentiometer for my rangehood fan. The manufacturer (FanTech) of the fan actually sells one (EC-10VHL) but I'm having a hard time trying to find a ...
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Identification of 3 pin connector for the power supply of the TI silent Model 703/707 Data Terminal [closed]
I want to restore a TI Silent 700 model 703/707 that lacks the power supply.
The power supply provides 20 VAC 35 VA with 3 pins
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AC Stepdown transformer blown troubleshoot
I've had a ring doorbell pro for about 5 years, it's wired directly to the following transformer output 1 & 4 (24v):
It's using the original doorbell wiring, which rightly or wrongly, was wired ...
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Food for thought: Which person has truth in this discussion on capacity and AC? [closed]
I have stumbled upon interesting discussion in the commentary section regarding safety of electrical engineering in home environment.
person1: AC voltage 'flows' even through insulator, fact.
person2:...
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How to find the power factor of a component when the combined power factor and one other power factor is known? [closed]
Problem:
A 2000 volt-ampere with a power factor of 0.8 lagging is combined with 500 volt-amperes of
synchronous motors. If the overall power factor is 0.9 lagging, find the power factor of the
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DC bias vs AC voltage change rate on MLCC capacitors
I'm looking at this 10uF X5R ceramic MLCC capacitor.
I know that ceramic capacitors which aren't C0G have an significant variation of their value depending on voltage, temperature, aging, and ...
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A scheme to control a number of ceiling light bulbs being on with a single switch [migrated]
I have a ceiling light with two bulbs and only two wires (live and neithral) arriving to it (220-250v AC) and a SPST switch. I want to connect one bulb directly to those wires and I want the other ...
