How to tell if my machine has a PWM power supply.

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prcdslnc13
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How to tell if my machine has a PWM power supply.

Post by prcdslnc13 »

Just what the subject says. How can I tell if my K40 has a PWM power supply? I ordered the machine and the DSP upgrade at the same time and both are to arrive on tuesday. I figured I would hold off on the power supply until I knew for sure. The machine I ordered was this one:
http://www.ebay.com/itm/151241036035?ss ... 1439.l2649

If it doesnt and I go a head with the DSP upgrade what differences will I see?
Tech_Marco
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Re: How to tell if my machine has a PWM power supply.

Post by Tech_Marco »

Take a picture of the power supply (inside of the case). We can't tell by seeing the outside of the machine.
If it is not pwm, the result is of engraving won't be as good as a PWM does. Plus, if the connection is different.

Marco
prcdslnc13
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Re: How to tell if my machine has a PWM power supply.

Post by prcdslnc13 »

Cool thanks Marco. The machine and DSP controller will be here Tuesday I'll post pictures when I get them.
prcdslnc13
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Re: How to tell if my machine has a PWM power supply.

Post by prcdslnc13 »

Ok Laser came, heres the power supply. Im guessing by the big green resistor its not PWM. What else can I look for?
Attachments
Laserpower.jpg
Tech_Marco
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Re: How to tell if my machine has a PWM power supply.

Post by Tech_Marco »

This is not a pwm power supply

. Marco
prcdslnc13
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Re: How to tell if my machine has a PWM power supply.

Post by prcdslnc13 »

cool thats what I figured. Ill get my order in today!.
tele
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Re: How to tell if my machine has a PWM power supply.

Post by tele »

And what about this one ?
Is this PWM power supply ?

https://drive.google.com/open?id=0B6Ayo ... nhZX1ZKNUk

Thanks,
Tele
laserdude
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Re: How to tell if my machine has a PWM power supply.

Post by laserdude »

As indicated in the lower right of the photo, it is a PWM power supply.
tele
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Re: How to tell if my machine has a PWM power supply.

Post by tele »

At first, I would like to know what is PWM, what does it mean in context of a laser P.S. ?

I know the meaning of the word, I know what the term means.

Where is the pulse-width modulated signal here ? What does it mean : "PWM power supply" ? Would that be "PWM controlled/controllable power supply" ? Its not the same at all, you know.

Or does it mean that the high voltage output of the P.S. is pulse-with modulated ? (I don't think so, but it could be that, why not, not clear at all, although interrupting, pulsating high voltages might have very unwanted consequences)

That connection you are pointing at, is a simple analog potmeter output, 0...5V, to control the laser power, in the original K40 settings.

How do you know that, it can be a PWM signal as well ? Ignore the text on the photo, it could be wrong.

Do you know this P.S. on the picture ?

What does that mean what Marco says :

"If it is not pwm, the result is of engraving won't be as good as a PWM does."

If its not controllable by PWM, but you control it with PWM, then the result won't be so good ? Does it mean that ? Sorry but it makes no sense.

I'm asking these stupid questions, because the discussion here is very strange. You are talking about technical questions, but no one wants to know what is what ?

Nothing is clarified, nothing explained, and no one cares ?

If I wanna be sure , then I should buy a P.S from Lightobject ? Thats the sure thing ? Is this the reason of the secrecy ? Or really no one knows the P.S what you can find in thousands of K40 machines since the last year ?
weeb
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Re: How to tell if my machine has a PWM power supply.

Post by weeb »

I had the same issue when I bought my first K40, I was worried if my power supply would be PWM capable. I went and researched it and found that in the last 10 years the majority of power supplies are PMW compatible. That wasn't good enough for me, I had to understand it. Apparently It is cheaper for power supplier sellers to make them pwm, it's only a small chip on the board, I can go into the why's and wherenot's but if you want to pm me I will explain why. I am in the process or writing a document and will post it when I have confirmed what I think is a simple issue, but I have seen so many times on this board what is PWM? and is my powerv supply capable.

I am trying to make sin wave a simple explanation, but I have to make sure what I am puting up is current (pardon the pun).

weeb
MicroBill
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Re: How to tell if my machine has a PWM power supply.

Post by MicroBill »

Weeb - Using a square wave might make it easier for you.

I explain PWM when doing presentations on LEDs and ways of dimming them. I tell them it's like turning a light on and off very quickly. If my on time is equal to my off time then the PWM is 50% and the light is half as bright.

I guess if you're musically inclined you could compare it to notes and rests.

Bill
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