First draft of the power supply. Have not annotated the parts yet

Lasers
,
21

Is the the one you were telling me about on instrucabuls

22

Excellent!!
Do you have circuit for 80 or 100 watt power supply

23

Here is another version of the schematic https://www.digikey.com/schemeit/project/k40-lps-2-EFKO7C8303M0:

I do not have one for 80 or 100W

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24

Its locked

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25

I do not know why it is locked, itā€™s set to share.
In the meantime here is a pdf

K40-LPS-2.pdf (531.1 KB)

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26

Don, I forget which K40 forum it was but one of them had the designer of the original K40 on it and he stated when he designed the PS for the laser he specā€™ed that it needed a 24VDC supply but since heā€™d already put in the 5V he hacked in a weak 24V 1A to prototype with. Then he said the manufacturers disregarded his recommendation and used the onboard 24V for the stepper motors. It was for this reason one of my first mods was to install a 24V 5A PS for the stepper motors and keep the heat of the over taxed LPS 24V load out of the LPS.

27

I am not convinced the 24V is only 1A nor overtaxed. It may be capable of up to 4A. I never took the time to analyze the switcher design and I did not test under load because I was going to use an external supply anyway. Among all the supplies I looked at only one had a 24V problem and that was not caused by the output side failing ā€¦ that wonky switcher circuit did.

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28

Great! very helpful.
Thank you sir

29

Sir if I apply standard power formula P=I x R for given 40 watt power supply e.g P=40mA X 23000 volts then result is 600W, but rating is 40 watt why? (I assumed 30-50mA)

30

Correct, the conversion from electrical energy to optical energy is very inefficient. There is power lost as heat and that is why the laser is cooled.

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31

Sir, How to design tube that matches power with power supply? In other words how to determine tube parameters like its dimension to find its wattage? Or power scaling of tube.

32

I donā€™t know as I am not an optical engineer.
I am not sure I understand the question.

What are you trying to accomplish?

These may help:

https://www.citefactor.org/journal/pdf/Design-and-performance-of-a-Cutting-CO2-laser-for-industrial-non-metallic-materials.pdf

https://www.repairfaq.org/sam/lasercc2.htm

https://iopscience.iop.org/article/10.1088/1742-6596/274/1/012058/pdf

Google ā€œCO2 laser designā€ for moreā€¦

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33

I am studying Co2 laser construction and its corresponding power supply. I want to make my own prototype, initially 80 to 180 watts, These documents are very helpful.

Thank you for documents. :slight_smile:

34

Got it.
Be very careful as these power supplies are LETHAL.

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35

Yes especially flyback.

36

Sir actually I am stuck in input power formula (Pin=?) for cavity,
(overall I want tube input wattage and matching power supply wattage)

37

Sorry but I do not understand your question?

38

Hello Sir,
I am ready to construct this power supply, At this stage I want to identify parts.
like:

  1. What is FLM (L2)? What is it part number to buy it from market?
  2. Current sense transformer T2 is UU1045. Am I right?
  3. PWM T1 Transformer. What is it part number to buy it from market?

Thanks

39

I will check again but my supplies do not have part # for the transformers.

If you donā€™t have one, get a LPS and scavenge the transformer parts that way. You can buy a new one or get a dead one, there are lots of broken ones sitting in maker sheds.

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40

Here is what I found. I updated the schematic with these #'s.

I did not try these parts # to see if I could find the manufacturers.
If you find them please let me know.

Note I do not know if all vintages of these supplies have the same xformers.

K40LpsXformerLabels
K40LpsXformerLabels4032Ɨ3024 2.08 MB

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