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Kenneth Breaux
08-03-2017, 12:29 PM
Hello,
New to Sawmill creek and first post.
I recently acquired a Chinese 3040 40 watt laser engraver running Lasercut 5.3. I got it at a steal because of this issue and was hoping to find some help here. After hooking up everything and got it ready to run I just simply made a cut pattern in the shape of an oval then exported it to the machine. I noticed that when I would fire up machine laser was burning when door was closed and off when door was open. I put in small board and closed door and it immediately started burning a spot at the start point. When I started program it would burn a line to the start of the oval. Then laser would turn off and follow route of oval. The laser would turn back on and burn a path back home and stay on till I opened the door.
Any Ideas?:(:(:(:confused::confused::confused:

Kev Williams
08-03-2017, 1:12 PM
Not to be rude but that's funny... does the laser stay on when parked?

I have no idea what would cause that, hopefully Dave Sheldrake or one of the other guys who understand controllers more than I do will see this and shed some light :)

Kenneth Breaux
08-03-2017, 2:04 PM
Yes.....as long as door is closed laser stays on. The only way to turn it off, is to power off or open door.

Matt McCoy
08-03-2017, 4:41 PM
I would try a default factory reset on the controller first. If that doesn't help, you may have an issue with reversed wiring or a bad controller. Be very careful.

Kenneth Breaux
08-03-2017, 6:51 PM
I believe it is reverse wiring. But was hoping someone else has had this issue. How do you do a factory reset?

Bill George
08-05-2017, 8:31 AM
First what controller do you have and frankly I would think the machine is wired wrong. I would contact the people who made the machine to see if they have a wiring diagram. The controller manufacture might have a generic diagram.

Kev Williams
08-05-2017, 11:29 AM
I'm no electric guru, but even if something is wired totally backwards, on is on, off is off; circuit is closed, or circuit is open, controlled by a switch, and it doesn't matter which part of the circuit is chosen to be open or closed. Ford had millions of vehicles recalled (2 of mine) because the cruise control system was "wired backwards", where the ground was used to open and close the CC circuit rather than the hot. This created a fire hazard, but didn't affect the function of the system.

The problem as I see it is a switching issue, for some reason whatever's firing the laser thinks on is off and off is on...So either the controller is messed up, or the software telling the controller what to do is messed up. Since the controllers in Chinese lasers seem to have a fairly high failure rate, I'd just change it out. They're not that expenseve, and a little ebay searching might turn up a used one for sale cheap...

Bill George
08-05-2017, 12:40 PM
Or the "Run" button is stuck on (or jumped ) so whenever the door is closing showing a safe condition the machine runs and fires.

Kev Williams
08-05-2017, 10:23 PM
I was thinking about that, that maybe the 'fire' button is stuck on and 'actual' on may be canceling it out... that scenario would reverse the firing!

I tried this on my machine, but when the fire button is pushed, other buttons don't work, and when running, the fire button doesn't work... But then, mine isn't messed up!

The 'button fire' circuit may be messed up within the controller and is overriding any normal safeguards...

Kenneth Breaux
08-06-2017, 6:08 PM
First guys, thank you for your input.
The manufacturer I guess is somewhere in China since it is a Chinese laser and I would not know what is the company since there are no logos on the cabinet other than the numbers 3040. I do not even know if it is a 40 watt laser other than that is what the guy told me.
I looked all over the inside of the cabinet and the card that I think is the controller is a Leetro MPC6515C. I will do some research on that. Just wanted y'all to know I appreciate your input.
I was able to look at the inside of another laser and I saw wires that were reversed on what I think is the power supply for the laser (the card with the laser test button). I reversed the wires on mine and thought that was the fix since I closed the door and the laser stayed off. I hit the laser button and it did it's short burst from the laser. I was excited and thought it was fixed. However, I ran a program and the axis drives moved as expected, but the laser never fired. I tried 3 different programs with same result. Arg.
Thanks again.

Bill George
08-06-2017, 6:16 PM
You need the connection diagram for your Leetro controller. Do some google searches and see what you can find. Or contact the people you purchased from?

This took me all of 30 seconds to find..... http://www.rabbitlaserusa.com/Manuals/MPC6515HardwareManual.pdf

Kenneth Breaux
08-06-2017, 6:29 PM
Thank you Bill for the PDF, I will go through it and my controller.

As far as contacting who I bought it from, it was an individual through Craigslist and he has no documentation on it because he too bought it from someone else. I assume I am the 3rd or 4th owner of this laser because of its issue.

Dave Sheldrake
08-13-2017, 2:29 PM
door switch is a normally open, it closes the fire circuit when the door closes.You can bypass it by jumping the pins on the 6515

Also check "Start Delay" on the top control pad, that can make them do some funky stuff

Kenneth Breaux
08-13-2017, 3:17 PM
Thank you. Will try that.

Joseph Shawa
08-15-2017, 6:19 PM
I once changed a power supply (the box with a fan that is under the machine) and wired plugged in to it the same way as the previous supply. The machine fired when it was turned on and stayed on. Check the wiring on the power supply.