Ballast resistors?

[Things]

Hey guys, I've seen a few pics of those cheap K40 cutters that everyone seems to have, and they all have 50K ballast resistors in series with the laser tube!

I have a power supply very similar to this, http://www.lightobject.com/40W-PWM-CO2- ... y-P71.aspx

Do people still use ballast resistors with these as well? I've never seen any mention of it, and the diagrams never show any ballast resistors, so I was assuming that maybe the PSU's in the cheap K40 machines don't have internal current limiting?

Regards,
Dan

[Tech_Marco]

It is used to limit the current to the laser tube. The original K40 came with a lousy power supply. And, the controller wasnt good either in regard to power control. FYI, the laser tube isn't a 40w but 35w. The power supply of the K40 or our power supply can output up to 26mA which is too much to power a 40(35)W tube. Current of 26mA is actually needed to power a 80W laser tube in full power. Of course our 40W power supply can't be used to power a 80w tube because higher voltage is required, not just current.

Bottom line, it is up to your controller to decide whether the giant green monster is needed. For most PSU, except for the old Shenhui PSU, you don't need the little green monster.


Marco

[Things]

Hi Marco, I have one of your DSP's. Will I need the ballast resistor still?

Regards,
Dan

[Tech_Marco]

No you don't need it. But you must set the 'max_power' current through the Manufacturer Parameters by using LaserCad. It's the master output so that current output from the power supply never can exist the amount you set there. To do so, you need a current meter to monitor the max current during setup. I'll set up the % from 75% and then hit "Laser" to test the output and make adjustment accordingly.


Marco

[Things]

Hmm OK, how much would it be to include a current meter in with my XY stages and mirrors/lens order?

Regards,
Dan

[GeraldJ880]

I merely finished the style of 70-640 an electric power dining room table for the K40 (also name D40K) lazer device. The particular finished merchandise will be easily obtainable in in relation to two weeks. It will eventually appear much better than your movie demonstrating because the many pieces will be delivered to the manufacturing area regarding anodization process. The base, and the figure will be dyed throughout either Orange or Environmentally friendly color. The particular dining room table features a forty two series going electric motor. Controller and the motorist seriously isn't involved but accessible coming from the look. Selling price is actually $115 as well as throughout DO-IT-YOURSELF pack. It will consider 45~50min in order to work it. It may rasie 5lb target and the travelling distance is concerning 6. 5cm (2. 5"). Little but ought to be helpful ample to manage many job on this tiny K40 device.

[NickWL]

Oh! I have to laugh...
Sorry, but the thought of putting a dining room table into my K40 (and maybe sitting a small family down to eat at it) - Thank goodness the motorist doesn't have to be involved else we might have to park his car in there too!
Thank you - just too good to pass up Gerald!
Come back Marco - all is forgiven

[Tech_Marco]

Sorry but I'm kind of lost here and not quite get it. Motorized dining table for K40?

Marco

[parsifaldruddle]

He means z-table, fellas. Sounds like a scissors lift similar in design to the PWRTB640 on here, but with a NEMA 42 stepper, in dk40 size, pumpkin coloured to boot. May also be available in Grape or other 'EF' colorations. (I think his sister at university or that slacker cousin of his that surfs all night, sleeps all day told him to mention 'Environmentally Friendly' someplace in his ad...) He's nearly finished the design, he's got to get the pieces over to the anodizer, film his demo, available in two weeks or so. yadda yadda yadda. Sounds like he may be developing a separate controller / driver for the table stepper / is concerned about connecting the table to the '40, but he'll git'er done. So, base price $115 plus shipping from 'over there' and he'll offer it as a DIY kit, too. Now he gets a little garbled - he either means to say it'll take 45~50 minutes to assemble, or 4.5~ secs to raise it, becuase if it take 45~50 minutes, we're probably better off just stacking honeycombs. He admits the 2.5" travel range may be on theminimal side, but believes it still to be of value for many, many jobs that might be required of a DK40.

This guy sounds like Sergei 'Gerry' Jazkolasku (?) (I left out the umlauts and funny diacritics) - kid I used to run guns with in Ecuador/Niccy/G-mala for my uncle in the '70s. That goofball had a thing for orange, too. Didn't get the camo-up-in-the-jungle thing really. He liked the orange cause he was always worried we'd get washed out to the 'deep ocean' - we ran the coast mostly but sometimes we'd shortcut straight from Tecojate or Champerico to Esmeraldas or Tumaco - and that's all deep water - no comforting shelf there. I gotta tell ya, he did have a bit of a point - that side of the strip, the pacific side - it can feel pretty bleak some days - not much for islands around there (subduction zone and all that) 'cept for the galapagos - and they're NOT like Carribbean Isles. It'd be funny if that's him, because he was not any sort of 'environmentally friendly'. His take on recycling was 'Throw it over, it sink, it rot, it recycle!'. He added more than his share to that pacific junk-gyre - plenty of empty gallo beer bottles - the one's with the bird head on 'em. Man, even if it's not him, nice memories... there was this girl in G-mala (on the Caribbean side) - gave me my first real scar - file that under 'Whatcha don't do on the banks of the Dulce'. "Y ¡ay! de aquel que con ciega locura, sus colores pretenda manchar!" where'd them forty years go?

so, ballast huh?

[NickWL]

The big advantage of orange is that you won't have to change clothes when they drag you into Guantanamo!