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Re: KH-7050 Laser dead

Posted: Sun May 19, 2019
by Chris Medcalf
It sounds like your estop switch is faulty, or at least not allowing power past it. On my machine, the estop cuts power to everything except the light and the electronics bay fan, which seems to be all you have working. Possibly you have reconnected the switch wrong.

Re: KH-7050 Laser dead

Posted: Tue May 21, 2019
by Josh Bern
So I finally got back to work on the laser.

I’m looking at the e-stop because now I think that may be the problem. I measured the voltage of the two terminals coming out of the e-stop and I get about 110V. I tried to close the switch and it still said 110V. Could that be the problem? Is the switch broken? What other terminals can I test? Thank you!

Re: KH-7050 Laser dead

Posted: Tue May 21, 2019
by Gene Uselman
Is your laser 110V or 220V? If it is 220v, that might be one leg of the 220. If 110v- yes with the Eswitch not pushed you should get 110 on both terminals.

Re: KH-7050 Laser dead

Posted: Tue May 21, 2019
by Josh Bern
It is 110V and I'm getting 110 from the e-stop when it is pushed and not pushed. Does that make sense?

Re: KH-7050 Laser dead

Posted: Tue May 21, 2019
by Josh Bern
Alright, I bypassed the e-stop and blew up some alligator clips while doing so but I can confirm that was the problem. Now, where can I order a new switch? What model is it? Thank you! I'm so happy :D

https://photos.app.goo.gl/yDLyXDNVkackLCnSA

Re: KH-7050 Laser dead

Posted: Tue May 21, 2019
by Josh Bern
Also, how can I safely bypass it in the meantime without burning up wires?

Re: KH-7050 Laser dead

Posted: Tue May 21, 2019
by Gene Uselman
[Safely] attach both wires to one terminal. I am not sure I have ever used an emergency switch on anything. It is kinda like the horn on my car, my sweetie sez 'Honk at that fool' and I don't really know where it is. I guess I am such a slow mover that I don't have emergencies.

Re: KH-7050 Laser dead

Posted: Tue May 21, 2019
by Jeffrey Aley
I recommend that you get a friend who is an electrician (or who is very familiar with electricity) to help you.
After turning off the power and unplugging the laser, your friend will need to carefully examine the EMO switch and how it is wired in your machine. For example, is it wired with two NC contacts (one for Line and one for Common), or is it wired with just one NC contact (Line only)?

Once that is determined, your friend can bypass it; use at least 14AWG wire and insulate it properly.

When replacing it, do NOT buy a cheap Chinese EMO switch. This switch is for safety (such as when your laser catches fire - oh yes, it will) so you want to be sure it'll work. Get one from a domestic supplier (Grainger, etc.) that is UL-Listed. The new switch should be rated at 15A or 20A, preferably the latter.

And as I've posted before, never ever use the "convenience" electrical outlets on the back of the machine. (You didn't say that you did, but I thought I'd mention it). Get one of these instead: https://www.amazon.com/Tripp-Lite-Indiv ... 219&sr=8-5

Regards,

-Jeff

Re: KH-7050 Laser dead

Posted: Tue May 21, 2019
by Josh Bern
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!

Re: KH-7050 Laser dead

Posted: Tue May 21, 2019
by Bryant Prenger
Seems as if you got it figured out! Congrats.

Im having the exact same problems you were however mine is dead dead with nothing at all coming on. (same machine too)
Heres what ive done.

1. Changed fuse to known good fuse.

2. Bypassed estop switch with no change.

3. Verified Voltage going to both Laser and 24v Power supplies.

4. Checked fuse in laser power supply -good

Anyone have any ideas?