Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [star]

29 questions
6
votes
2 answers

Three-phase motor Delta/YY connection diagram and windings troubleshooting

I am trying to troubleshoot this 1.4 kW three-phase motor and I'm unsure how its internal windings are interconnected or whether they are shorted. On the plate it says "Delta/YY 400 V", and I'm not sure what YY means. Most articles online describe…
Robert Lee
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2 answers

Delta-Star Combination Exercise

This post is regarding exersise 4-8 from the following book: Hughes Electrical And Electronics Technology 10th Ed. Here it is: Let's focus on what I tried for solving part (b) : Since this is an exercise under the chapter for delta-star…
Stamatis
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2
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2 answers

Motors Delta/Star connections to VFD

I've selected 230/400V motors (delta/star) and corresponding 400V VFDs for pump motors. Now I've been asked why I haven't selected 400/690V motors (delta/star), that are the standard and usually connected in delta. The manufacturer says there that…
Yoda Master
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1 answer

Why don't the currents clash in a 3 phase delta connection?

Consider 3 windings, a, b and c. L1 is connected to A, L2 to B and L3 to C. The 3 windings are then connected in delta. If we could freeze frame the voltage waveform where L1 and L2 are positive maximum and L3 is negative, what will the current…
Ph3ng
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1 answer

Why connect a 3-phase alternator's star-point to a rectifier bridge?

I noticed while troubleshooting a Denso alternator that the stator's star point was connected to the rectifier bridge. While probing with a multimeter, I think the schematic looks something like the below: Source:…
Kenn Sebesta
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1 answer

3-phase star transformer connection with no neutral for wind turbine

I built a wind turbine a while back and have been using it to power lights in my house. It gives out 3-phase in star setup with no neutral. Neutral is buried in epoxy resin in the casting. It feeds into a three phase rectifier down at the house and…
Omasín
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1 answer

How to solve this star delta problem?

Please help me solve this star delta problem: My attempt: What to do next to solve this completely?
Shivam Jaiswal
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1
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1 answer

What is the correct way to solve this problem?

I first solved it by converting the two star connected networks into delta networks and further solving them. Then I solved by considering one star, converted that to delta and then used parallel series concepts. If anyone can tell me what's the…
Chandradhar Rao
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0
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2 answers

Multiple ground

In my design I have four different ground: Ground: from USB for step up and battery charger IC. Ground1: for a split supply (virtual ground). Ground2: for the input signal reference. Ground3: for the output signal reference. how do I physical…
Status Re
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0
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4 answers

LTspice error, "Matrix is singular" for 3 phase circuit

I have been searching about it online but all I can find is info about a transformer. Am I missing something? Here is the circuit: This is the circuit I am trying to make:
ELIZ
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Torque developed by Star Connected rotor

The current in each phase of a Y-connected rotor winding is 200 amperes. The resistance per leg is 0.003 ohm. Determine the torque developed by the rotor at a slip of 3%. I don't understand how to approach this. Like I don't know how to complete the…
LoneHyena
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Problem figuring star delta starter circuit

I know the basic functioning of star delta motor starter configuration but kind of stuck on my current project which uses old L&T starter panel. I can't figure out the terminals like A1, A2 (coil power terminals), NO (used with push start the coil)…
Rishabh
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2 answers

CAN bus expander circuit

I am trying to design a CAN bus expander. In this case I could implement star topology of multiple buses in parallel. It would avoid having problems with reflections and delay. For this purpose I prepared a simple schematics, that basically…
unalignedmemoryaccess
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Power measurement in star three phase balanced load

I had a doubt, in a balanced star three phase arrangement: Using two wattmeter method, we obtain power readings as W1 and W2. (which may be unequal). Let us take W1=5 watt and W2= 6 watt for instance and phase current to be 10 ampere. However from…
programmer
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1 answer

Only 3 wires in 3 phase motor terminal box

I have a 3 phase motor with the nameplate below At the terminal box you have your standard 6 pins labelled u, v, w, u1, v1, w1. However, the u1, v1, w1 is not connected on the terminal block but instead hardwired for star configuration inside the…
Luqmaan
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