This tag refers to alternating current mains power. It usually applies to voltages with >100V RMS, but can also be used for ex. 24V industrial AC power.

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Need to convert 0-10VAC (alternating current) to 0-3.3VDC (direct current)

I am using a sensor that outputs a 0-10 VAC (alternating current) and I need to convert this signal into a signal within 0-3.3VDC (direct current) to feed into an ADC. What is the best way to go ...
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2answers
68 views

Can a voltage source be DC and generate a sawtooth signal?

Pretty much what the title says. I'm fairly confused with this simple question. Shouldn't waveforms which change amplitude be AC? EDIT: So this is about a RAMP Type DVM (Digital Voltmeter). Can the ...
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0answers
23 views

AC Motor Starter Capacitor - humming sound after replacement [on hold]

A tumble dryer stopped working and I found it to be the starter motor capacitor (when switching the dryer on, the drum would not spin but if you manually started to spin the drum, the motor would kick ...
3
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1answer
78 views

Do AC voltages on datasheets refer to peak voltage or Vrms?

I'm attempting to find a relay to switch UK mains voltage (230Vrms); this gives a peak range of approximately 325V, -325V. Consider something such as the datasheet for this relay. It has a ...
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2answers
44 views

24 VAC source unable to drive servo motor

Here's my power supply (schematic except without the transformer since my source is already at 24 V AC and using a 100 uF electrolytic as my smoothing capacitor): 24 VAC rectifier -> 100 uF smoothing ...
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0answers
34 views

Analyzing a circuit with given effective values, freshman EE

Here's the circuit: simulate this circuit – Schematic created using CircuitLab Values: Voltage shown at the volt-meter, 11V Current shown at the ammeter, 5A Current generated at the ...
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1answer
23 views

quick question about AC SPST rocker switch

I'm replacing the motor control switch in this toaster and wanted to be certain about how it should be installed. It's a normal SPST neon rocker switch with A, B and C for terminals, and B-C being ...
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2answers
58 views

What do these symbols in ac connectors stand for?

I'm trying to use a relay to control my house lights with a electronic circuit. I'm familiar with 5V DC circuits, but I've never played with AC before. My relay has three connections, which I assume ...
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2answers
37 views

controlling a DIY spot welder with a momentary push button switch?

I have a 240v to 12v transformer even bigger than a microwave transformer and i want to control how long it is switched on for in the range of 50-300 milliseconds to spot weld things. I was thinking ...
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3answers
77 views

Why is the capacitor considered lossless, even if it can store/give out energy?

They say capacitor is lossless because average power is 0.But contradicting this is the fact that the energy stored/disipated by a capacitor is (1/2)CV^2.How and why is this?
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2answers
52 views

What are the differences between an AC and DC coil relay?

If a DC coil was just a coil, it would saturate. If an AC coil was just a coil, the magnetic field would drop to zero at 120 Hz and the relay would chatter. Presumably the designs in some way prevent ...
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0answers
13 views

Adding another circuit to a full panel [migrated]

Is this the right forum for this question, as browsing all I see is regarding more "electronic" than AC electrical? Regardless... I'm looking to add a hot tub, and after my basement build out a few ...
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0answers
35 views

How does buffer prevent loading effect?

Buffer is said to be used for impedance matching and preventing high flow of current.But how does it prevent Loading effect?How does usage of buffer overcome the dependance of the terminal voltage ...
2
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2answers
52 views

Low Voltage AC Smoothing Capacitor Calculation

I have a 9V AC source which will have a max load of 100mA. I'm trying to figure the value of a smoothing capacitor with less than a 10% ripple. I don't have a scope or else I'd just try a bunch out. ...
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1answer
40 views

Good way to switch AC/DC (Rectifier) in welder

I am building a homemade welder out of microwave oven transformers. I would like to have ideally an on off switch and then an AC/DC switch or just having one switch would work too. AC 120V 60Hz ...
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1answer
40 views

This circuit has floating nodes in LT Spice?

This is the circuit I'm working on. This circuit probably doesn't work as intended to begin with, but that's not the point. LT Spice keeps complaining that it doesn't have a reference to ground. I ...
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0answers
67 views

Unable to get clear answer on which breaker flips first [migrated]

I've rented a space where the transformer and main panel are fenced off and I can’t access it without calling the landlord. He lives rather far away and is the only one with the key and that kind of ...
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1answer
27 views

AC steady state circuit analysis using mesh

I have attempted multiple tries into this circuit problem and I am getting no where. For this question I have to use mesh analysis to find \$V_x\$. \$V_x\$ is across the right branch containing the 3 ...
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2answers
100 views

Does any company manufacture American AC power plugs with insulated pins?

In Australia and some other places, good-quality AC power plugs have "insulated pins". This means that there is a short length of insulation covering the base of the pins. Darren Yates writes that ...
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1answer
26 views

Finding current in AC circuit, coupled coils

Freshman introductory problem, AC circuit.Coupled coils. Here it is: simulate this circuit – Schematic created using CircuitLab So I need to find the current through the voltage ...
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0answers
36 views

Calculate lower-bound for the total average power

I'm studying for an exam and have come across a question question about power lower-bound. In my lectures we have gone through AC peak voltages, \$\sqrt{2}\cdot V_{RMS}\$, I'm not sure if it's related ...
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0answers
42 views

High pass filter DC blocking equations

Given a 12 volt DC supply to a potential divider circuit and a coupling capacitor connected to a 40 mVp AC, how would I confirm that the resistance between ground and capacitor is low or high enough ...
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0answers
78 views

How to measure AC voltage without a voltage divider using microcontroller

I have to measure AC voltage of the mains supply 180-220 VAC through a microcontroller. I have been wondering how to measure it without using a voltage divider. Since the resistance may wear out with ...
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1answer
80 views

How or where can I get a 120VAC to 3.3VAC power supply?

I'm using a safety gas valve (commonly found in household stoves) for a hobby project. The valve is rated for 3.3VAC, 3.6Amps. The problem is that AC-to-AC power supplies are quite rare, and I had no ...
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2answers
86 views

why do rectified voltage boosts after adding a capacitor?

So I found this 9V 1A AC power supply laying around and decided to make a DC source. I rectified and added a capacitor to make things a bit even. After adding a capacitor my voltage boosted from 9V ...
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2answers
59 views

What would be the results of two bridge rectifiers in series?

What would be the side-effects of placing two bridge rectifiers in series? The question stems from reading how some devices are manufactured with a bridge at the input to make reverse polarity ...
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0answers
37 views

Bicycle AC hub generator is noisy when open circuit, not noisy when closed. Why?

I bought a wheel with a hub generator (Shimano DH-S501) that I installed on my Surly Long Haul Trucker. The generator comes with a plastic cap that covers the terminals of the generator and keeps the ...
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3answers
98 views

How to safely destroy an AC Adapter? [closed]

I purchased an AC adapter for a nintendo wii. It hasn't worked and every fuse I put in to it appears to blow. The seller has offered to refund me and send me a new one if I send him a photo of the ...
2
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1answer
87 views

Is there a pattern to where various industrial AC voltages are used?

AC voltages in the "low voltage" class vary quite a bit. I've seen nominal voltages of 208, 220-240, 277, 380-415, 460-480, 575-600, and 690 VAC. Past that I don't see anything until medium voltage ...
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1answer
72 views

Why isn't there a voltage drop across the Main Wires?

As far as I know the power to my home is directly coming through a Step-Down transformer, so why isn't there a voltage drop and how are all the houses hooked up to the same transformer getting the ...
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votes
1answer
37 views

Is matching an infinite switch rating to a heating element required? [closed]

I want to use a Robertshaw universal infinite switch rated at 15 Amps to power a heating element to boil water in a stainless steel tub. The voltage is 240 VAC. A heating element greater than 3600W ...
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3answers
66 views

Series LCR experiment

i am doing a series LCR experiment for measuring the resonant frequency taking, R= 100 ohm; L= 40mH; C=0.1uF. I am using a 10KHz audio oscillator having 10V p-p as the input. I have fixed the input ...
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1answer
44 views

What is the right way to wire a power inlet to a switch to a dual-primary transformer?

I have a fused power inlet with a voltage selector (Schaffner FN1394-10-05-11). I want to connect it through a separate DPDT switch to a transformer with dual 115V primary windings, and make ...
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3answers
118 views

What is this on power supply unit?

I need to power a large 180W LED lamp that runs on DC so I got this transformer that is 12v × 15amp. But I don't understand the labeling on the terminals. There are 2 +V terminals but no -V ...
0
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1answer
75 views

Reversed biased diode polarity in circuit

I have to find the operating interval of the diode in the following circuit.. NOTE: The DC source has its positive pole grounded. My work so far is this.. \$V_i>-1.5 V\$: the diode does not ...
0
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1answer
53 views

120VAC Digital Potentiometer

I have an AC PWM dimmer board from eBay that uses a potentiometer to control the dimming level. I want to replace it with a digital potentiometer that would serve the same function. However, it needs ...
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2answers
42 views

How to calculate the RMS of an AC PWM?

I am looking at a servo, which is driven by PWM. The PWM signal itself modulates NOT DC but a sine AC, so when Throttle is set to 100%, I can see a rather nicely drawn sine wave. But when Throttle is ...
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3answers
58 views

Capacitor and inductor power factor

I need an explanation about the leading and lagging power factor at electron level. Case1: In a inductor it has the lot of free electrons are ready to move when we applied a voltage(AC or DC). If we ...
0
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1answer
53 views

Issue powering Shop Vac with Car Battery (via Power Inverter)

I am hoping to run a shop vac off a var battery (this car battery will not be attached to a car). I am hoping to use this vacuum in a remote part of our yard away from any conventual power resources. ...
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1answer
33 views

working of Relay switch for driving high voltage ac appliances

Explain the working of relay switch for driving high voltage ac appliances? also explain how it works in embedded system?
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1answer
70 views

Wiring a step down transformer

I have a Transformer with the following writing on top of it : TFM-00053 CLASS B 130°C Z150H E154515 LEI-4 8B25 it has three thick wires on one end : Blue Brown Red ; the resistance ...
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1answer
39 views

Relation of current with frequency and voltage

I tried to solve a numerical problem but I got stuck and I think it very necessary to have its solution. I will draw certain basic conclusions when I would found its solution. The question is: An ...
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2answers
215 views

Touching an AC wire [closed]

What will happen if a person touches a 220V AC live wire while he/she is not in contact with the ground?
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1answer
69 views

Does order matter when it comes to AC power? [closed]

Is there anything about electricity or the electrical design of AC power strips that dictates in what order the devices should be plugged in? When I say, "in what order", I am referring to the ...
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1answer
49 views

Is there a rightside up when plugging in an AC to DC power converter? [closed]

When plugging an AC to DC converter into an AC outlet, does it make any difference at all if the wall wort is "upside down" or "rightside up"? Is there anything about the electrical design that would ...
0
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2answers
41 views

Can rms voltage change when peak to peak remains constant?

Can the rms AC voltage change with frequency? I have connected a DSO to the audio oscillator(having 10V p-p). Peak to peak voltage remains constant on changing frequency(10 Hz to 100KHz) but on ...
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0answers
50 views

Calculating signal attenuation for AC?

So we've got this; simulate this circuit – Schematic created using CircuitLab Which I've been told is equivalent to the sum of it's Coutputs to an AC signal; simulate this circuit ...
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2answers
36 views

Can a planar transformer replace a laminated transformer for 50Hz AC conversion?

I have seen planar magnetics transformers even with isolation up to 20 kV. However those devices seem to be designed for DC/DC conversion in 100 kHz range. I am wondering whether low frequency ...
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2answers
77 views

Very High speed response AC coupling

my goal is to achieve a HIGH SPEED RESPONSE AC COUPLING, as I want to totally get rid of the DC component even though its changing rapidly I have a signal coming from a sensor ( a proximity probe), ...
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2answers
67 views

Wiring up a AAA power toy to Pinball lighting supply

I'm trying to wire up a toy powered by AAA batteries (3vdc @ .09A) to the lighting circuit on a pinball machine (6vac @ 4A) and I was wondering what the best possible solution that I can keep small. I ...