Hello Forum! I have two very quick questions, and one medium length question. I have been trying to build a CO2 laser, and have had trouble getting the signal to activate the laser power supply. So I'm scrapping everything I have done and starting over. So I'm asking opinions on the following two questions: 1. Which controller is more suited for a CO2 laser, BlackBox or xPro V4? (I'll be using UGS and GRBL) 2. Which Meanwell Power Supply, 12V/29A or 24V? (I know it sounds like a dumb question, but I'm really not sure what power I need to run the LPS, motors, etc.) Also, any other advice on using these controllers and Power Supplies (other than the obvious... BE CAREFUL!!!) I want to buy this immediately so I can start on this build and need to get moving on it, so your quick response is MUCH appreciated!!!
In terms of driving a laser, the same. Decide on other specs like motor current, etc instead 24v. Better motor acceleration when drive voltage is higher. Laser PSU powers itself. I'll extend on that with BE VERY CAREFUL! Always have one hand behind your back when working on these (So current cannot form a path across your heart), Always wear appropriate goggles. Build a SOLID METAL enclosure, acrylic is cut by lasers, which makes it useless as a safety barrier.
@Peter Van Der Walt Thank you for replying to my questions! So I'm a little confused... the 12V/24V mains can't actually power the 40w CO2 laser tube?
No CO2 Lasers need Kilovolt power supplies! You can run little Diode lasers directly off 24v, 2.8-6w max, and thats 445nm (Blue/UV) which only works on Organics. CO2 lasers excite at 12-20,000v (12-20kv) and produce light with a 10600um wavelength (infrared) which is absorbed well by organics and also plastics Lots more research for you! CO2 lasers can really get complicated!
@Peter Van Der Walt Well, that makes complete sense! Duh on my part. I really appreciate your response! Can I control the Laser PSU with one of these controllers? As far as the other stuff, I'm just running 3 NEMA 42 motors (using parts from the Eleksmaker A3)
Nema 17s? Yeah, but note that CO2 PSU wiring depends a lot on "which one you got" too... If its one of the decent ones they have the following pinout WP = Water Protection = Grounded out by a flow sensor in the water cooling line (GNDed when water flows, Open circuit when water flow is obstructed/off - Disables the tube to prevent it cracking if theres problems with water cooling system) IN = Power setting = Analog voltage, or tie to 5v if you run PWM into TH/TL (As for Grbl) - can also be wired with a potentiometer to set Maximum power (scale the PWM) TH = Trigger High = Wire to Grbl PWM pin - With IN tied to 5v (100%) the PWM signal on TH will scale power accordingly. Note super cheap PSUs doesnt like PWM! TL = Trigger Low = not used, inverse of TH - triggers when pulse goes low. Some people wire a switch to TL<-SW->GND to act as a TEST button 5V = 5v output for the IN signal / potentiometer GND = Common Gnd for logic signals
@Peter Van Der Walt Sorry, yes NEMA 17s. This is the LPS I have. Is it correct? 40W CO2 Laser Power Supply for Engraving Cutter Machine Dual Voltage | eBay So, like on the xPro, can I use the Spindle PWM (highlighted gray) going to the TH on the LPS? If not, how would I connect the xPro the the LPS?
The ebay listing isnt really showing the pinout, so consider this the generic answer: Yes... if the PSU has a TH. Those cheapies tend to have TL (Labelled just L (Low)) and no TH pin, so check your closely If it has no HIGH input you can Wire in an inverter circuit to turn the high pulses into low pulses for the TL/L input R1 and R2 = 1K Ohm use a NPN transistor e.g. 2N3904 Wire +V to 5V Vs = Connected to PWM pin, and Ground connected back to the common GND VO = inverted signal to TL/L
@Peter Van Der Walt That is very awesome of you to take the time to show me that circuit! Thank you! This is a better diagram, of what I have: http://www.cncoletech.com/download/PS40-3-g.jpg So on this one, the VO signal from your (very awesome!) circuit goes to the "L" pin #3 on the 6-pin connector (third from the left)? Does the "G" Pin #4 need to return to the xPro V4 "Analog Ground" on the Output Connector?
GND should be common among all components: From the PSU GND, to Controller GND, to LPS Logic GND. To avoid EMI issues one would want to use star grounding, common point somewhere, i'd use the PSU's [-] terminal. Be aware of FG = frame ground = dont common that with DC ground as arcs from the tube to your frame/enclosure will happen (Dead tubes send arcs out the sides)
@Peter Van Der Walt Sorry, which digital ground? I see several of them... which one goes with "Spindle PWM Voltage"?
@Peter Van Der Walt Awesome! Thank you so much for your help with this. I'm going to order the xPro V4 and the components you specified and try to figure this out! Thank you again for your help and time!
Also consider the BlackBox - beefier stepper drivers = faster acceleration = something you'll miss when you try do raster engravings on smaller drivers
@Peter Van Der Walt Thanks for the advice! Will definitely do... unfortunately seems to be out of stock, which kind of stinks. So then I'm assuming use the 24V Power Supply, yes? (again for NEMA 17 motors) Also, everything we've been saying to connect it to the LPS would just use the PWM and the GND on the "TOOLHEAD" outputs, yes?
OK so I know this is an old thread but I need some assistance with a K40 controls conversion to a black box controller. Let me start by saying I am not a newbie to the black box I converted an old ender 3 into a diode laser engraver using a black box last year with no issues. But I can't seem to figure out what is happening with my K40 conversion. I have everything wired I set up x and y (scaling) with no issues (I don't have a z axis). I have the laser control working the problem I am having is this thing won't home. Not sure exactly why, my end stop limit switches are working (tested via troubleshooting on Openbuilds Control v1.0.207). Is it because I don't have a z axis and it has to do that axis first? If so how do I disable Z? How do I enable single axis homing?
Grbl expects a Z axis in default config. So flash the 2 Axes build: OpenBuilds CONTROL > Wizards and Tools > Grbl Flashing > 2 Axes We did this step: https://github.com/gnea/grbl/wiki/F...r-i-have-a-pen-plotter-and-dont-have-a-z-axis for you in the 2-axes build we supply with CONTROL.
Oh yeah I notice in an earlier reply he (Peter) said he didn't have pin out for the PS on ebay. Here it is incase anyone needs it in the future.
Also if anyone converts from the NANO 2 board did some digging and omh'n so I could reuse the ribbon cable, here is what I found (the highlighted yellow is all I reused- and ignore the colors, they are the color wires I attached to the ribbon cable connector)
Hi All, I know its an old post but I see that almost every other CO2 laser posts redirect here so I think its better to ask in this thread. I have a 40W laser tube conected to a 130w capable LPSU. I wired followind advice readed here and other threads except my LPSU actually have a TH pin and wired directly there. I'm using lightburn software. My problem is when I press test buton on LPSU it fires acording what I set in potentiometer but when I tri to make a cut with lightburn it fires really low power despite % I set. I suspect I have to wire in a different way (PWM to In and other pin -maybe direction?- to TH) but I'm not sure. In GRLB settings Lightburn and blackbox $$30=1000. Using GRLB machine not, GRLB-M3. Thank you in advance
Potentiometer should have a GND too (So it works as a voltage divider) GND on left left, 5V on right leg, IN on the center (wiper) leg
