Wood a powered USB help

LightBurn Software Questions
1

Afternoon guys and gals, I have now got air assist set up and seems to be running ok, but there seems to be signal problem from the computer…
Ok…all was going great, set up another small job of 3 spacers with some engraving the engraving got done the Air came on and I got 2mm of the cut and laser just froze with the laser still on…
The only way I could stop the laser from continually firing was to turn off and pull both cables (power and Data)…
Still could not get it to work so I changed the Com port and it made a clicking sound and then I switched back to the right Com port and sometimes that helps and others not so much…
So my thought was the Data cable ( I think that’s what it’s called) but that was replaced by me about a year ago for a better one, So I again thought maybe I should try a powered USB Hub…
Sorry I have no technical info or pictures I was so frustrated I just shut down I come inside to calm down before heart attack..
The cable I’m currently using has this info on it if it helps…
USB Shielded High Speed Cable
2.0 Revision
28AWG/1P+AWG/2C
ROHS Compliant
and has gold plated ends

Cheers Merlin…

2

It might also be caused by the power spike the pump is creating. Does it also stop when you do not activate the pump?

3

Melvin… From memory no.
I always do the engraving first and had has never stopped during that only when air comes on for the cutting…
But I will check tomorrow morning after a restful nights sleep ( yeah nah) just me being hopeful…
Cheers for now…

2 Likes
4

Well I did for once have a decent sleep…
Anyway You are probably right about the power spike… anyway to fix that…
I played a bit this morning and got nowhere, in fact at on stage the laser froze and I couldn’t get to respond at all…
I Reset the laser and still nothing and the command window said I needed to reset the Home position which I did and the GRBL was set to 2 which I was sure was wrong so changed that to 0, that worked now have the laser back but no Air Assist through LB… Well can’t have every thing but will have another go on Thursday cause will out on Wednesday (doctor and stuff like that)…

Cheers Merlin…

5

I had a similar problem when i changed computers. I had the cable connected to a non powered external USB port. When i plugged directly into the computer USB port the problem was corrected. So I changed to a powered external USB port adapter and that corrected the issue

6

I’m going to town tomorrow so will get the cable checked and looked at…
But if its going to be the power, My computer, monitor, pump, and laser are all on the same power outlet…
Will this make a difference or is there a better way of powering everything…
Pictures of what I require wood help as I am not that good at understanding some of the terminology in electricity…

Cheers Merlin…

7

Well all is ok again as long as I run a 30 meter cable to the outside PowerPoint on the house…
My thought was to bury a new cable to the house but the expense is to much at the moment…
Then I thought could I run another cable from the main workshop through to the laser workshop… see terrible plan…
The red line wood be the new line about 30 meters the blue line about 8 meters…
Asking all electricians out there if this wood work… I can run the blue line myself but not the red line…

Cheers Merlin…
Wire to Workshops.lbrn2 (143.4 KB)

8

Hello Merlin,

Are you using the Sculpfun pump for the S9 in your profile?

This pump gets power from the laser over the same power supply. They mention that : " When using the air pump, you must use a 12v 4 Ampere power adapter."

9

Aaron thanks for reply…Can you tell me how the power comes from the Laser when without using a relay, to switch pump on/off…
When using the pump without relay it’s not connected to the laser and all is fine (I just have to manually change the air low…
But when I hook up the relay it freezes to laser when LB switches to engraving from cutting… but if I use an extension cord for the pump that’s not on the workshop system all is great and works as it should…
Cheers Merlin…

10

I see, there are two Sculpfun pumps. - A smaller, black one that takes 12V DC power directly from the laser. With this one, it’s important to use the stronger 4 Amps supply.

image
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And a larger one (probably what you have?) using AC mains power from a wall outlet:

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This one is controlled manually uses a relay inside the pump, triggered by the laser’s output. Relays are supposed to galvanically isolate the two circuits to avoid ground loops and yours might have a problem there.

There’s probably an easier solution than running a separate power cord to the workshop. Let’s see if someone else has an idea.

In the meantime, you can manually activate the air assist by entering M8 (or M7) in the Console Window and press enter. M9 will turn it off again.
Do you see any errors or disconnects when you turn it on this way?

11

Thanks for the reply, It’s late now like 10:30pm…
Yes I have the older pump that uses mains power, and if there is a relay in that why do I need another relay to run Air Assist via LB like this

relay_control-1024x576
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Which is what I have done and what the problem is with it power spiking…

12

It turns out, I lied when I said the larger pump was using a relay inside! It’s controlled only via the knob of the mains power cable and therefore not controllable via software. - Unless you add the relay yourself as you did.

Does the layer with air assist enabled still run through if you:
a) unplug the relay from the controller?
b) unplug the pump from the mains? Does the relay click on?

13

Ok First up Cut, the pump comes on, when finished the pump goes off and the engraving starts then the second cut the laser freezes…
Your answer to A is Yes, but B answer is No
Does the relay click on, No

How is the relay meant to work it is all damn confusing for me

I think I should just invest in another laser like the SF-AF 20 watt…

Cheers Merlin…

14

That’s contradictory to what you said before.

You said that everything worked if you connected the pump’s power to the separate mains cable from the house. Is this still the case?

I expected the job to run through and trigger the relay if you didn’t connect the pump at all.

So, if you have the relay attached, the job fails. Do you see any errors in the Console Window when the laser stops? - Send us a screenshot please.

If you used the relay in your picture, you should hear it click on. It even has an led indicating the state of the signal.

Which exact relay did you use? Pictures of your wiring could help us understand.

15

Another thing to consider is the relay itself. I only use relays that have a “flyback diode” attached. This keeps down electrical noise when the relay turns off and on. A long time ago we referred to it as Reverse EMF but it is sometimes called “flyback” or “back” voltage.
There is often a schematic on the case of the relay that shows the diode.
Here’s is a sample of a relay with a diode. I’ve also attached a link that describes the reasoning behind using a "flyback diode.

Diode Relay
Diode Relay708×613 200 KB

16

Well what a day, I thought I wood make a video of the whole thing so I started with extending the wires from the pump to the relay so I could put the relay on the work area in the video shot…
Set up the phone on a tri pod and lined everything up made a small image to cut engrave and cut again with the air assist set up…
Pressed start button and the air came on and started the interior cut when that finished the pump turned off for the engraving after the engraving finished the air came on again and finished the cut to my amazement…
Tried that 3 more times and it done as it’s supposed too…
By this time it was time for some lunch so I turned everything off as I wood after I had finished for the day…
After lunch I turned all on again and tried to do the same again and nothing it just froze (Bugger).. I tried to change the com port like I usually do and change it back again that normally gets it going again but nothing…
Console window said about can’t find connection, Turned all off again and tried console window cant home Homing not set in GRBL, machine settings was blank and I tried to move the laser head and it was frozen could not move all until I turn the laser off…
By this stage I said bugger it and turned all off and came inside and looked up on the internet for a new laser…
My brain is not wired for electronics or electricity so for now …Thanks for trying Aaron …

17

@Geriatric Good point about the Back-EMF. This can and will definitely cause issues when you control the relays directly from a digital pin of a microcontroller like we have on laser controller boards.

The relays in the picture before has precautions for this problem in form of this rectangular part, the optocoupler to galvanically isolate the two circuits, and the transistor that switches the relays on from the separate DC in. (Most Digital pins won’t be able to directly power the coil of a relay)

image
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@nzmerlin, it sounds like you came far already since it worked a few times.
We still don’t know which relays you used exactly. If you could send us pictures of the wiring and pump you are using, we may find a clue.

You can also right-click the “Devices” button in the Laser window to reset the current device connection

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Do you see more than one COM port in the drop-down and does one of them disappear when you unplug the laser? - That would be the one to chose. You should also hear the Windows “bleep-bloop” sound when you plug in the USB cable.

18

The problem discussed here is a very common issue with first generation Sculpfun lasers. The reason is the weak power supply in most cases. So an EMI filter in front of the power supply or different power lines usually solve it (as it did for Merlin as well). A better power supply might also increase cutting power in some cases.

1 Like
19

Melvin thanks for your input as well as Aaron, before I go and take pictures of my setup wood an emi whatever that is (I checked and some are expensive) wood one of these to the trick.
Here

Cause I do have a12v and a 24v laying around doing nothing…

20

Ok had a hellva morning trying things but nothing so I typed out every thing as I went, hope I got it right and at the end there will be some pictures of the pump and how I wired it and the relay I used…
Computer on LB Loaded

Waiting for connection…
Grbl 1.1h [‘$’ for help]
[MSG:‘$H’|‘$X’ to unlock]
error:9
G-code locked out during alarm or jog state.
[MSG:Caution: Unlocked]
ok
[VER:1.1h.20190825:]
[OPT:V,15,128]
Target buffer size found
ok

Laser on

Laser Head at home Lower left Head can be moved manually
Pressed then Home Button and laser clicked and the Head Froze/Locked can not move manualy.

Laser window Com port is 11 only other port is 3 Clicked on com 3 Waiting for connection clicked back to com11 laser clicked

Waiting for connection…
Waiting for connection…
Grbl 1.1h [‘$’ for help]
[MSG:‘$H’|‘$X’ to unlock]
error:9
G-code locked out during alarm or jog state.
[MSG:Caution: Unlocked]
ok
[VER:1.1h.20190825:]
[OPT:V,15,128]
Target buffer size found
ok

The laser unlocked and can be moved manualy.

Can not be moved from the Move window, pressing the Home button in Move window Locked up the Head again.
Unfroze/Locked by changing to Com 3 and back to Com 11.

When I Right click on Devices I hear a small click on the laser Head.

I think I need to do the rehoming thing again some of the settings don’t look right…

I Type $ in console I get
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]

I type $$ I get.
$$
$0=0
$1=5
$2=46
$3=186
$4=0
$5=0
$6=0
$10=153
$11=0.000
$12=-0.000
$13=0
$20=0
$21=0
$22=1
$23=0
$24=0.000
$25=0.000
$26=166
$27=0.000
$30=0
$31=0
$32=0
$100=-0.000
$101=0.000
$102=0.000
$110=0.000
$111=0.000
$112=0.000
$120=0.000
$121=0.000
$122=0.000
$130=0.000
$131=0.000
$132=-0.000
ok

This was all done without the relay connected, I disconnected it the night before to see if it wood make any difference, it did not…
I did not cut the wire on the pump cable I unsoldered it from inside and extended the wires…

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