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Re: KH-7050 Laser dead
Posted: Tue May 21, 2019
by Josh Bern
My knowledge is pretty limited but have you checked to see if any breakers have been switched off? My machine doesn't have one but some do.
Apparently the laser power supply tends to die and may need to be replaced. Other than that, I'm not sure.
I wish I could help more.
Re: KH-7050 Laser dead
Posted: Tue May 21, 2019
by Bryant Prenger
Both the fuses I could find were good. I did order a new 24v power supply. I'm gonna give that a try. I have voltage going into it but not out. I'm not sure that'll do it tho.
Re: KH-7050 Laser dead
Posted: Wed May 22, 2019
by Jeffrey Aley
Bryant Prenger wrote: Tue May 21, 2019
Both the fuses I could find were good. I did order a new 24v power supply. I'm gonna give that a try. I have voltage going into it but not out. I'm not sure that'll do it tho.
Good job isolating the problem. There's one other thing I'd do: disconnect the wires from the output of the 24V power supply, and then test the output voltage. The reason for doing this: if the outputs are shorted somewhere, then you'll get no voltage out of the supply. By removing the wires, you truly isolate the power supply itself. Thus, if you know there's voltage coming in, and nothing is connected to the output, you can tell if it's the supply (or some component within the supply like a fuse), or if it's actually something downstream of the supply.
For the High-Voltage supply, is there a fan that comes on when it's powered up? Also look for LED lights and a test / pulse button.
Re: KH-7050 Laser dead
Posted: Wed May 22, 2019
by Bryant Prenger
Jeffrey Aley wrote: Wed May 22, 2019
Bryant Prenger wrote: Tue May 21, 2019
Both the fuses I could find were good. I did order a new 24v power supply. I'm gonna give that a try. I have voltage going into it but not out. I'm not sure that'll do it tho.
Good job isolating the problem. There's one other thing I'd do: disconnect the wires from the output of the 24V power supply, and then test the output voltage. The reason for doing this: if the outputs are shorted somewhere, then you'll get no voltage out of the supply. By removing the wires, you truly isolate the power supply itself. Thus, if you know there's voltage coming in, and nothing is connected to the output, you can tell if it's the supply (or some component within the supply like a fuse), or if it's actually something downstream of the supply.
For the High-Voltage supply, is there a fan that comes on when it's powered up? Also look for LED lights and a test / pulse button.
I'll definitely do that with the 24v. As far as the high voltage power supply goes, I have voltage to it as well but nothing at all happens. It's as if it's not getting a "signal" to turn on. No fans, lights, and the test button do anything.
Re: KH-7050 Laser dead
Posted: Wed May 22, 2019
by Gene Uselman
Josh Bern wrote: Tue May 21, 2019
Thank you for the help. I successfully bypassed the e-stop by connecting the terminals. Everything works now.
Thank you as well for the info on electricity tips. Now I need to find a new switch but my research on Grainger only finds 10A switches.
What about this one?
https://www.amazon.com/HONEYWELL-87943- ... ay&sr=8-12
If you have a good option, please send the link. Thank you so much!
Josh- you might want to check the mounting hole size unless you have tools to enlarge the hole in the case. I worked for Honeywell 55 years ago as a technician building and calibrating the guidance and control systems for the Lunar Expeditionary Module. God I am getting old.
Re: KH-7050 Laser dead
Posted: Wed May 22, 2019
by Josh Bern
So I measured and have a 25mm hole but the emergency stop plate is 22mm. Therefore, I think I need a 22mm one. Size is no longer an issue.
I tried to find a 20A UL certified one but it is very difficult. Also, I need to make sure there are 4 contacts because some only have 2.
Do you have any recommendations? You seem incredibly knowledgeable and experienced
https://www.amazon.com/Baomain-Mushroom ... way&sr=8-1 (This one is closest to the original but cheap Chinese and I was not recommended to use a cheap one.)
https://www.grainger.com/product/DAYTON ... ton-30G250 (this might work)
Rather, I was told to use a UL certified reputable switch.
https://www.grainger.com/product/HONEYW ... ton-22A627 (This only has to contact points I think)
Please let me know which you recommend. Thank you!
Re: KH-7050 Laser dead
Posted: Wed May 22, 2019
by Doug Fisher
You might look at Cloudray and Lightobject.
Most E-stops fail because people are using the sockets on the back of the machine to power other devices. Do not use those sockets for anything. I think Gene mentioned this before.
Re: KH-7050 Laser dead
Posted: Wed May 22, 2019
by Josh Bern
Yep. The only reason I used the back plug was for my blower which was a Japanese/Chinese plug type. I ordered an adapter and will use a well rated Belkin power strip.
Everything you said makes a lot of sense to me. Thank you!
Re: KH-7050 Laser dead
Posted: Wed May 22, 2019
by Doug Fisher
Yep. The blower is probably the worst thing you can plug into those ports. I think most of the classic gray squirrel cage blowers demand 600 watts.
These lasers have wiring intended for 220 volts. The wiring is just barely adequate for 110 volt systems.
Re: KH-7050 Laser dead
Posted: Fri Jun 14, 2019
by Jacek Kruczynski
This happened to me also. But I was lucky, had to replace one fuse in the machine with a spare they provided.
Just in case someone have same issue, here some pictures:
1.jpg
2.jpg
3.jpg
4.jpg
Works fine after replacement
