Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [ac-polarity]

13 questions
3
votes
2 answers

Transformer winding voltages shouldn't add in additive polarity?

In the figure at right, I believe the terminals are at the following potentials: H1 = 0V H2 = 120V X1 = 0V X2 = 30V Doesn't it follow that the potential difference across H2 and X1 is 120V (not 150V)? Source
artist_and_not_EE_by_training
  • 398
  • 2
  • 12
3
votes
2 answers

Why is this power cable sometimes polarized and sometimes not?

I have a handful of power cables like this: Some have polarized male plugs, while others are not polarized. Given that the female end appears to be reversible, why are some of them polarized? I have an LED television that came with a polarized…
RockPaperLz- Mask it or Casket
  • 315
  • 1
  • 7
  • 20
3
votes
2 answers

Three-phase Y and Delta Configurations Polarities

Please take a moment to look at the three-phase Y and Delta configurations pictures below (The pictures are screenshots taken from the “All About Circuits” online book). The first picture (Y configuration) shows the neutral node with negative…
T555
  • 1,569
  • 2
  • 17
  • 27
1
vote
3 answers

Merely flipping secondary winding shouldn't affect transformer polarity

The polarity test for a transformer determines whether it has additive or subtractive polarity. I understand that convention is to recognize X1 and X2 on the secondary winding as, respectively, the negative and positive terminals, but does the…
artist_and_not_EE_by_training
  • 398
  • 2
  • 12
1
vote
2 answers

Diode - output waveform of a network

Question: Determine the output waveform for the network(assume that all diodes are ideal) The book says for the positive half-cycle it will be like this: Similarly I think that for the negative half cycle it will be exactly like this except…
Utshaw
  • 187
  • 6
  • 16
0
votes
1 answer

What is the name of this plug, and which side is line and which is neutral?

What is the name of this plug, and which side is line and which is neutral? (Image from Wikimedia Commons)
Math Keeps Me Busy
  • 18,947
  • 3
  • 19
  • 65
0
votes
3 answers

Which of these wires is positive and which is negative?

I know that in DC circuits the colour code is often (but not always) that red is positive and black is negative. On this AC mains wiring the wires are blue and brown. Does anyone know which is which? It's for a light bulb (image below.) I wish to…
Mito
  • 409
  • 9
0
votes
2 answers

Insulate active or neutral?

If you can only insulate active or neutral, which should you choose? Does it matter? Is it important? Is one better than the other?
voices
  • 1,039
  • 1
  • 15
  • 29
0
votes
1 answer

How do I solve transformer numericals with additive polarity?

Ok, so for subtractive polarity in transformers(dots at the same side of the windings) E1/E2=N1/N2 But if it's subtractive polarity E1 and E2 are out of phase so shouldn't E1/E2=-N1/N2 Edit: Ok here is what I tried out. I just need to understand…
Nigel Goveas
  • 71
  • 3
0
votes
1 answer

Effect of Reversed Phase Polarity on Active & Reactive Power of 3-Phase System?

I am trying to investigate the Power/Energy of 3-Phase System under Different Faults. I have a Three Phase Source and Load, Load is balanced i.e same phase angle and current (Phase-Neutral V = 230 rms, Current = 10 rms) for a power factor of unity…
BetaEngineer
  • 87
  • 1
  • 2
  • 13
0
votes
1 answer

Create a polar cap with a diode?

I'm trying to order components, so I can make a board following this circuit. My problem is, I cannot find any 0.1uf capacitors, that are rated at 275VAC. The highest voltage I can find, in stock, is only 50VAC, unless I want to buy a couple…
LittleRain
  • 3
  • 2
0
votes
1 answer

Capacitive transformerless power supply, AC polarity problem

I have implemented a "Capacitive transformerless power supply" to control a microcontroller-based circuit that contains capacitive touch sensors, and I had an "AC polarity problem" Surprisingly, the circuit behavior became affected by the polarity…
mina_g
  • 1,355
  • 4
  • 18
  • 21
-1
votes
5 answers

What is the point of polarized plug in home AC?

Given the fact that with AC, electrons move back and forth, implying there is no real flow from A to B, what is the point of a polarized plug, since either way should do. The only explanation I have is that we know which side in the plug is live.
Cherry
  • 47
  • 5