Questions tagged [transformer]
A transformer couples two or more AC signals through a magnetic field. Often used as galvanic isolation and to transform one AC voltage to another.
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How can we determine the load on the secondary of a transformer in order to achieve nominal current on it?
I have the following question:
How can we find the Load that it must be connected be on the secondary in order to achieve nominal current on it?
My solution is the following:
By applying KVL:
$$VphA = ...
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Is there a rote procedure for testing a transformer removed from its circuit other than checking its windings' continuity and output voltages?
For context, I'm repairing an old JVC CD player stereo unit with a polarized plug, hence the onboard transformer. Also, hence the absence of a service manual of any kind.
It attempts to turn on upon ...
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Why is the power loss in an inductor less than that of a transformer of equivalent inductance by an order of magnitude?
I tested two inductors and two transformers close to 1 mH and there was very little power loss in the inductors when driven by a square wave and yet the transformers had significantly higher power ...
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Why does my audio transformer step up voltage but not drive my headphones loudly?
I'm experimenting with audio signals and a transformer, and I'm confused by the results.
My Setup:
Source: My Android phone (Itel A25) playing a music audio file at maximum volume.
Measurement: My ...
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In a 3-phase transformer, why don't the windings induce voltages on the other phases?
I suppose I have a poor understanding of the physics behind magnetism. As I understand a basic transformer to work - the primary winding produces a flux on the core which induces a voltage on the ...
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Current sense transformer
This is an RF current sensing circuit with a 1:100 (Primary:Secondary) transformer.
I want to derive a formula to calculate the current flowing through the primary circuit. I have written some ...
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How do I connect a PLL sensor on transformer output with two secondary windings to a diode rectifier load?
Background:
I am working on a project of modernizing a system for a lead acid battery charger. I will do this with a Vienna rectifier, that needs the current angle, that I get from a PLL, for control.
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How to properly ground and protect a 240V EV charger circuit fed from a 480V 3-phase panel via single-phase transformer?
I’m installing a 240V, 40A electric vehicle charger that uses a standard NEMA 14-50 plug. I only have access to a 480V 3-phase panel, which has sufficient capacity to power the charger.
After ...
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Best Topology for 300V - 1500V Input and 220V Output DC
I’m designing a flyback converter with a 1500V max input and ~220V output. The main issue is device limitations: a conventional flyback would need a MOSFET rated above 1500V, but most available ...
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How to design a transformer
What electrical quantities are to be found while designing a transformer whose power in kva and only input output voltages are given? What electrical parameters are to be found and what is the ...
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Why can't I get the magnetizing inductance across tertiary winding in a forward converter?
As per the standard magnetics theory, the magnetizing inductance (of an ideal transformer) can be placed across any winding. (Ref the accepted answer for this StackExchange question.)
Let me try ...
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LLC resonant converter "calculation"
I am working on an LLC resonant converter design,
Lm = 490 µH,
Lr = 90 µH.
My next step is to design the transformer. Could someone explain:
What type of transformer is typically used after the ...
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Do planar transformers need insulation between core and PCB?
There are multiple construction options for planar transformers. They can be implemented with separate small PCBs or integrated into the main PCB. They can be clamped or they can be glued as ...
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Radio antique audio transformer DIY?
Good evening,
Is it possible to recreate this small audio transformer at home. There isn't enough information in the schematic is there??
Thank you for any guidance.
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Single wires on a secondary transformer?
I am working on an old guitar amp (converting an Ampeg VT 60 to a Fender Bassman), but want to bring down the voltage. Working on bucking the AC using the 40v secondary (purple to green), but confused ...
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