[dgchessman2]

Hello folks,

I'll do my best to communicate the issue we're having. I'm not the most versed in the electrical system of our machine, but I ~am~ the one closest to a computer at the moment! Which means I'm drafted.

Background: Currently building a heavily modified Lasersaur, with almost entirely guts, as we weren't happy with the electronics they offered. Most hardware is from MisumiUsa, and most electronics are purchased though LightObject. Using an AWC-708cPlus as a controller, and 80w and 150w tubes, power supply, and chiller from Sinjoe Laser.

Frame assembly is finished (my department). Alignment and test firing had begun when we started noticing a frequent, reoccurring issue, which is why I'm here today. On firing, several things happen in quick succession:
1) Gantry speeds quickly towards Zero if anywhere else
2) Machine Zeros itself
3) Machine runs program and begins to fire/pulse.
..... and this is where the controller usually resets 4/5 times. Occasionally it will decide to run, and does so just fine.

We are, today, going through and checking individual wired connections, hoping to find an easily-tightened culprit. However, it's been asked that I post here in case folks have experienced something similar, and may be able to point us in the right directly.

Thanks ahead of time, guys!
~ Kaz

[KeithOKC]

Not an expert on building machines but I can make an educated guess. Sounds like either a A) power issue coming into the machine. Is everything grounded properly and do you have the proper voltage coming in? Does the machine flicker or shut off? B) OR you have something that's touching the frame, another wire, or any of a hundred other things that can come from wires not being properly put together and sealed. C) You could also have a wire out of place in a connector. If you think for any reason it's the power supply or power cables be very careful, lot of watts flowing through those machines.

[dgchessman2]

A) The machine flickers and resets, zeroes again, and often gets confused as to its location, causing it to slam quite loudly into the physical stop closest to zero. It's exceedingly unpleasant. It does not, however, power off.
B) We are seriously considering replacing the signal wire with a specifically shielded wire. If there are wires that need to be shielded, and wires that don't, I haven't come across the distinction between which is which before. We have a lot of equipment near the machine.... ventilation, water chiller, AC inverter, in the proximity of the machine, but nothing touching/mounted to. They sit on the floor underneath, on their own grounded socket.
C) Rightly so. We're checking individual wires for more sneaky problems that might be happening. Will update if anything shows up!

[Gozzie]

Turn off the laser power supply or unhook it and see if the machine runs correctly.
If it works properly without the laser then you may have a brown out issue of sorts
where the incoming power is not enough.( if you are running through an inverter or something like that)
You may have to up the size of the inverter.

Gozzie

[gfacer]

Sounds like the laser high voltage input line is shorting to the case to me....same type of issues when that was happening to me. Gets worse as the arc leaves a trail of conductive carbon....I don't recall the best method to clean that, but lots of insulation on the connection would be a big part of the fix.

[dgchessman2]

Gozzie - We did do a bypass on the laser power supply, running the program 'dry' with no laser activation. Works every time. But why would an issue with the laser power supply make its way back to the controller and cause reset? They are on different power outlets. No inverter.

Gfacer - I'm not sure I follow. Outlet to laser power supply? And you're suggesting insulation as a fix?

[gfacer]

Having the electricity arc through the air to the metal frame will, even if well grounded, screw up the control electronics momentarily. Then the machine will home again. The high voltage can jump a few inches easily, which is why tubes often have silicone applied to the wires, or high voltage electric tape works well to...that's the insulating I meant. To be clear, this is probably happening at the back side of the laser, furthest from the first lens

As for the going to home, that sounds like a software setting. I know my machines can reference home, a set position, or just where its at rest when the program starts.

[Gozzie]

Well you have partially isolated your problem and can narrow your focus.
The first thing I would do is make sure the power supply and the controller are on the same power feed. Not the same circuit inside the machine but the same circuit feeding it.
You said they were on 2 separate outlets which could lead to a potential 220volt problem in the mix if wired incorrectly and they are out of phase. I doubt if that's going to be the problem
but you should check.

Do you have a milliamp meter on the negative side of the tube. Watch that meter closely and make sure you are not overdriving the tube causing further damage while testing.

As gfacer stated the high voltage side feeding the tube has a real potential to arc to the chassis and cause weird problems not to mention health hazards.
You are close and I know that you will work this out. To bad we all don't have spare parts lying around to make quick swaps. That would be to easy.

Make sure you are grounded good and double check all your connections including all the grounds and signal wires.

Also make sure your power supply is set to the correct voltage 120 or 240. Could be a switch on the power supply.

Gozzie

[dgchessman2]

Thank you guys. We're doing a dedicated wire-testing for a couple of hours tonight.

Will pass along all of this, and update as info comes in.

[dgchessman2]

Alright, updates:

- Laser fires via hidden-little-test button. And bonus points (as the mechanical guy writing now...>_>... ) the mirrors are currently aligned. 10-second fire twice.
- With the tightening of wires, gantry no longer loses sight of zero on reset. So even when it resets.... no slamming! ^_^ (...hate that sound)
- Communication errors persist.
- Laser frame is now grounded, and the DC power supplies have an extra to-earth grounding as a precaution. No improvement from this, however.
- Tester agrees that shielded signal line, if not all 3 controller-to-laser wires should be shielded.

I'm wondering: Do we need to give the same consideration to the white/red wires coming from the laser tube itself? And the question of whether the white wire needed to be tied to ground/the frame came up with no verdict.

Shielded wire is in the mail, should arrive soon.

[Gozzie]

Yes take precaution on the red wire from the tube. Make sure it is high voltage wire and or encase it in a silicon hose tubing
and try to route it away from the other wires.

I don't think you should ground the negative wire, as you already grounded the frame and the power supplies.
It looks like you are making progress. Be proud

Gozzie

[dgchessman2]

Insulated tube? That would be easy enough. Alright. We have plenty of heavy gauge rubber water tube lying around. More than enough.

[gfacer]

Insulated wiring all the way to tube, really really really without any path for the high voltage to travel. Not insulating the tube itself.

[dgchessman2]

We've got some heavy gauge insulated rubber tubing that I'm using now to double-insulate the main power wires going from the power to the tube itself. Not insulating the tube ^_^;; Using tubing as insulation.

Unfortunately it's been a busy weekend and the shielded wire hasn't shipped yet. Installation will be this upcoming week.

[dgchessman2]

Alright, these last couple of weeks has been slow. The guy doing electrical isn't around much (read: NOT my department!)

So far, we identified a short happening from the laser tubes to the frame. It was being grounded away, but that shouldn't have been happening at all. The design has aluminium brackets that house the laser tube. and one of those was touching bare glass. Got that wrapped up and tightened back down. Didn't fix the problem, though.

Got ferrules in the mail. Will be adding those tonight, just to make sure the terminal connections are not an issue.
Got charge and return wires on the tube housed in rubber, and isolated from other wires.
Replaced the signal wires with shielded wire.

There is a crackle.... and arc happening somewhere. The power-to-tube wire seems to do that very slightly, but somewhere in the power supply there is an arcing/crackling going on (pardon my course language, I'm the mechanical arm of the company)

With each small issue we fix, the behavior gets more stable. But we can't seem to get consistent behavior, nor nail down where North of the controller we're having issues.

To recap: Using controller get roughly 1 in 4 runs without a reset. Up from only occasionally originally, then eventually none.
Using Test button we've gone from 1 in 4 runs without a reset, to 4 in 5 tests without a reset, and long prolonged test fire.

But once we hit go, it heads to the job, and derps out more often than not.

[Gozzie]

Just checking on your progress.
Did you figure it out ?

[dgchessman2]

Sad to say... .no real luck so far. We've gotten more stability, but not a solution to the random reset.

Have gone back through wires, checked connections, reinforced Ground......

[Gozzie]

You say there's a crackle or arc somewhere. Maybe in the power supply itself.
I know it would suck to have to buy another supply just to find out. Maybe you can take
the cover off and look for signs of arcing.

If it works right without the power supply hooked up it seems that it would have to be the culprit
if all your wiring is worked out.

Gozzie

[dgchessman2]

Hey guys, another update, this time with photos.

Problem 1 - Power Issue - We swapped out for our other power supply, and saw immediate improvement. However, it was similar to what we had seen before; 3 resets, and then the machine would run for a while.

So! I had it functioning enough to get the mirrors aligned, and decided to move on to the focus lens and cutting some test boxes. Behavior was consistent as mentioned before. Test box was clean.

Problem 2 - Throughout all of this, our X Axis motor has been making.... 'squirly sounds'... I thought it was the pulse setting from the software, as the steppers make odd noises when this is off. However, after dialing this in, the X motor still makes odd noises. May or may not be related to....

Problem 3 - (Now with photos!) Complex object cutting seems to cause an intermittent issue. Oddly enough, as we started doing the more complex test fires, our Problem 1 started kicking back in... on either power supply. Simple boxes seem to cut fine. Complex objects mean multiple resets before a single success. Once it's running.... it does not ever reset except on stop/start/restart.

.... but something is either slipping, getting bad info from the controller, or perhaps possessed by evil spirits.

[dgchessman2]

Have a ground-test coming in the mail. We're honestly running out of ideas now. Our last theory is that a potential bad ground is turning our various components into little capacitors, as some of the parts seem to be retaining a static charge even when grounded to the frame and/or Ground.

Hopefully that will shed a little more light on this.