Digital laser power settings.

Lasers
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Digital laser power settings.
My K40 has the digital control board with three digit seven segment LEDs like others I have seen posted here, the power supply is the kind without an external current limiting power resistor.

I made a table of digital power setting and laser current measured by ammeter in the laser negative lead. Here are the results plotted as a graph. I do not now run the machine at greater then 75 on the digital setting, approx 18 mA. The laser strikes at just below 10, approx 3mA. I measured the current with both a digital multi-meter and moving coil ammeters.

Different setups could well produce different currents, I don’t know and I have nothing to compare against. I’m thinking of making an EHT voltage probe to see what voltage the tube is running at, I’ve seen an example on the net using a chain of high value resistors. hth David.

e4b51f05043cd22bb19d1e0f3f940577.png

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I’ll be setting my digital machine up this week, so will be interesting to see how close it is to your results.

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70-75% seem to match the max current recommended by most usual laser tube supplier (18ma). those pot manual or digital (in%) does the same, limit the current max for pwm (as a ceiling value) to protect the life time of the tube.
thank you for sharing.

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Thanks a lot, very useful.

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@David_Richards_djrm
Here’s my mA results, it’s way out from your’s but seems pretty close to my other machine.

http://s18.postimg.org/xqf8ty66x/image.jpg

apologies for the delay…