Questions tagged [ac-motor]
For questions about electric motors driven by alternating current (AC).
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Why does a motor or ceiling fan exhibits low torque after capacitor-to-inductor swap?
For quite some time, I have been curious about what would happen if I replaced the capacitor in my ceiling fan with an inductor. Here in India, we usually deal with a mains voltage of about 220 - ...
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Why do DC motors cost more than AC motors of the same power?
For high-power motors around 1000 kW, the price of a DC motor is much higher than that of an AC motor of the same power. I know there is a commutator and brushes, but I don't think that is the only ...
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Single phase 3-speed AC motor won't start spinning or spins in wrong direction
I have a Danby DPAC8399 air conditioner, and its fan motor started acting strangely. Sometimes, it it will only do a hum and won't start, and other times it will do that hum for a few seconds and then ...
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Help with (very) odd single phase motor wiring
I think this is my first post here.
I have little knowledge on AC motors, and this machine I am servicing (an old Balltrap/Clay target shooting machine) left me baffled. The below diagram is a ...
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Electrical Motors and Frequency
I was musing about electric motors after seeing one randomly on TV, and there's something I'm must be remembering incorrectly.
It's just a thought experiment, so I'm imagining some theoretical DC ...
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Induction Motor Wire Size
Capacitor Run Single Phase Induction Motor have very high starting currents, possibly in the order of 35-40 Amps upon startup for a 1 hp device, whereas the nominal current usually lies in the order ...
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1
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Old Record Player Motor Doesn't Have Torque To Start
I am restoring a jukebox from 1953 (AMI E-120). Everything is going fine except the main drive motor, an A/C induction motor, cannot start under the load of the platter. It starts fine when the ...
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Reversing direction of an AC universal motor
The problem: I have a table saw motor I am trying to use in a jointer and need it to spin in the opposite direction (permanently). I have had trouble finding an answer that I am reasonably sure ...
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Does current have to return to its source?
I am not the most knowledgeable when it comes to electricity, so apologies if my questions lacks necessary information that is needed to get a good answer.
I work with 3 phase electric motors, and I ...
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1
answer
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Pump motor fails to start when connected to a low frequency inverter via a long wire [closed]
I've been struggling with a submersible pump showing unreliable behaviour when connected through a long cable to a low frequency inverter.
The pump is used only once a week to fill up 3 5000 L tanks. ...
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How to solve application with power spike one time per 24 hour
We have a building where many similar systems run heaters and valves off a 400VAC, 3 phase, 63 ampere supply (45 kW maximum.)
Internal control software in each system turn the heaters and valves on ...
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Trying to understand this electrical diagram schematic on an AC motor that I have, particularly symbol between yellow and black wires
I'm new to electrical wiring and I'm trying to learn a bit and came across this AC motor which I have that isn't hooked up. I have attached the motor wiring diagram:
This is also the wiring ...
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Need help identifying wires on 3-phase single-volt AC motor (6 leads)
I'm far from an electrician. Just a guy trying to get some new life out of an existing piece of machinery.
See the image below, this 5HP motor comes from a heavy duty commercial treadmill. Based on ...
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What does "Brushless DC is an AC induction motor with built-in speed feedback" mean?
I found a quote
which states that:
"Brushless DC" is a marketing term for "AC induction motor with built-in speed feedback."
Is it correct? What is "built-in speed feedback?"
I found a decent ...
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Can we run an induction motor by sequentially applying DC voltage to the windings of stator?
We know that in induction motors, 3-phase AC input is applied to 3 windings of stator in order to generate changing magnetic flux in the rotor. What would happen if we apply 3 DC voltages ...
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