Cleaning Modified Sine Wave

SYNERGY

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Question: Won't the Power Supply on the PC "clean up" the modified sinewave input?
 

Alacrity

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Question: Won't the Power Supply on the PC "clean up" the modified sinewave input?

It does indeed. Devices that has motors like fridges, aircons etc. does not run smoothly on modified sinewave input.

Switching mode power supplies like your PC is ok but normal transformers will run warmer.
 

Thor

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What does it do under load?

What load are you talking about, a pc?

Cause that's what I'm. Running and I really don't see what the fuzz is about people going on and on in this thread about my suggestion that worked for me.


I assumed his not planning on running his whole house of it.
 

Alacrity

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Cause that's what I'm. Running and I really don't see what the fuzz is about people going on and on in this thread about my suggestion that worked for me.

If you measure it with an oscilloscope with and without the cap you have there I'm willing to bet the signal will look the same.
 

Alacrity

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How's that?

To change a square wave into a sine wave you need to remove about 30% off the energy. That is why a normal transformer will heat up.

So if your capacitor is not heating up (blowing up) it is not absorbing energy and if it is not absorbing energy it is basically doing nothing.
 

Alton Turner Blackwood

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OP, what sensitive electronics are you talking about?

All your equipment will work just fine, just don't plug in devices with an induction motor into the thing (fridges and washing machines)
 

Thor

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To change a square wave into a sine wave you need to remove about 30% off the energy. That is why a normal transformer will heat up.

So if your capacitor is not heating up (blowing up) it is not absorbing energy and if it is not absorbing energy it is basically doing nothing.

That's why I am not using a capacitor you find in your router board.

The one I am using is a 30uF 470volt stud mount.


It's handles my PC, that's why I suggested it originally, sorry of its not correct to suggest it.
 

AstroTurf

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That's why I am not using a capacitor you find in your router board.

The one I am using is a 30uF 470volt stud mount.


It's handles my PC, that's why I suggested it originally, sorry of its not correct to suggest it.

Just plug a desktop fan into it in a quiet room.
Listen to it for a few minutes.

Then plug the fan into a wall.
Listen to it for a few minutes.
 

xumwun

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Modified sine wave shouldn't really be a problem for a PC anyway.
The first thing most power supplies do is rectify the power into DC (Apparently most could actually run of DC).
 

Thor

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Just plug a desktop fan into it in a quiet room.
Listen to it for a few minutes.

Then plug the fan into a wall.
Listen to it for a few minutes.

That sounds reasonable I will do that and report back
 

AstroTurf

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That sounds reasonable I will do that and report back

Watch the fan blades as well.

Quick dirty way to estimate how clean your power is.

You can do it with cfl's and incandescent bulbs as well.
 

Archer

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That's why I am not using a capacitor you find in your router board.

The one I am using is a 30uF 470volt stud mount.

It's handles my PC, that's why I suggested it originally, sorry of its not correct to suggest it.

Have fun letting magic smoke escape.

You don't even know the equivalent resistance of the load, so how you chose that size cap who knows
 

fruitbat

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It does indeed. Devices that has motors like fridges, aircons etc. does not run smoothly on modified sinewave input.

Switching mode power supplies like your PC is ok but normal transformers will run warmer.

Really wow? I was worried about this... Thank you :) i think you just saved me some moolah. Just need to find one that has sufficient battery to keep my server, router and 3x lights running.

Thanks guys!
 

sovielenamen

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A comparable cheap autotransformer for the inductive loads should do it or not? I doubt that it will have to eliminate 30% of the energy, I would rather believe it is quite effective with the energy being buffered in the magnetic flux and smoothed on output. You introduce some inertia this way if I understand it right.
If I am wrong please tell me why or a link.
Another sine wave inverter is just byzantine....

Oh! Now look here, Thor is not so wrong in the end, some resistors and capacitors do it too, just fix them at the load (fridge etc.) where they can be adapted to the specifics and that's it. Pretty obvious and won't hurt when on the grid.
That is cheap and not hard to do.
Best solution as most devices work same or better on squarewaves anyways.
 
Last edited:

The_Unbeliever

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To change a square wave into a sine wave you need to remove about 30% off the energy. That is why a normal transformer will heat up.

So if your capacitor is not heating up (blowing up) it is not absorbing energy and if it is not absorbing energy it is basically doing nothing.

I'm very sorry, but I'm very, very, very sceptical about a transformer outputting a true sine wave. How does it do that?
 
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