tag:blogger.com,1999:blog-247130680149573043.post5330383047822584271..comments2024-03-21T02:26:58.014-07:00Comments on Don's Laser Things: Understanding the K40 Digital Control Panel???DonKJrhttp://www.blogger.com/profile/14497402158163702122noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-247130680149573043.post-42848295678702445592022-03-06T12:35:02.281-08:002022-03-06T12:35:02.281-08:00Don, I'm planning on putting in a current mete...Don, I'm planning on putting in a current meter for the laser, but would like to keep the 7seg LED power display. I don't/won't need the PB switches since I'll be using a pot for power control. The 0.1% display is irritating at best (at least with the PB switches) so I'm thinking on using only 2 displays. Do you have a circuit? PWM->7 segment should not be hard to do, but I like to see what others are doing before I make my own. Good article by the wayquequehttps://www.blogger.com/profile/11001625447727160939noreply@blogger.comtag:blogger.com,1999:blog-247130680149573043.post-40927744158195879802021-06-17T04:41:16.848-07:002021-06-17T04:41:16.848-07:00I know it is 2021 alread... I juste recently got a...I know it is 2021 alread... I juste recently got a K40 with the digital panel. I've added an analog current meter and did some testing with an oscilloscope. My PWM frequency is about 10KHz at 50% duty cycle. What is found is 100% (99.9% is the closest I can get) is only 97% max duty cycle, it could be as low as 93% although that may be the cheapy scope that triggers poorly. SO the ammeter is about 14mA max. What is an eye opener, is that at 40% power setting, the duty cycle is 50%. That is 8mA power, which is correct for my laser. With a pot at full power, I get 16mA.<br /><br />Another issue I think I am getting is when I use Meerk40t to drive the laser, the power is noticeably different than with K40Whisperer, assuming that for Meerka40t I set power on the panel to 99.9% and ppi to 400, in theory that is 40% power. Of course with K40Whisperer, the panel is set to 40%, which of course is actually 50% duty cycle, so K40Whisperer cut deeper. Sight, there goes my carefully curated settings file!<br /><br />Then of course there is the issue of Meerk40t doing a raster engrave. With even 20kHz PWM frequency, and Meerk40t "modulating" the pulses (ppi) for a given job, it may be that Meerk40t sends a "fire" when the control panel is in the off cycle off the duty cycle. This no burn. You can see that unless the pulses are synchronized, there will be no burns. In theory with a full 100% on time (in stead of 97%) it should not matter, and at a real duty cycle of 97% it should be mostly fine, but if you should use the control panel to limit max current to say 50%, your day is bound to be ruined. The same can be if you have a true 97% duty cycle and want to engrave at 5% power from Meerk40t. You can only hope when your 5% comes up, that its not in the 3% off time. Meerk40t should increase its rate of fire with pixel density and head speed, so it may get worse.<br /><br />So in this case, I think a simple switch to short the PWM to full power for Meerk40t and open it to test fire at lower power or when I want to use K40Whisperer for whatever reason. I have an MCU with two true DAC convertors which I may try and hack in if anybody have a schematic for the controller. :-)Bergiehttps://www.blogger.com/profile/02636029340783960057noreply@blogger.comtag:blogger.com,1999:blog-247130680149573043.post-5608179175528850382019-11-20T05:08:16.514-08:002019-11-20T05:08:16.514-08:00Hi Walter,
Sorry but I cannot do a video of the di...Hi Walter,<br />Sorry but I cannot do a video of the digital panel as my machine does not use this type of panel.DonKJrhttps://www.blogger.com/profile/14497402158163702122noreply@blogger.comtag:blogger.com,1999:blog-247130680149573043.post-69780959383854105912019-11-19T21:30:01.033-08:002019-11-19T21:30:01.033-08:00looks and sounds like it copies the way GRBLlaser ...looks and sounds like it copies the way GRBLlaser works with diode lasers except it does not allow software control of laser power and I do not know why as you set the power in the gcode generator.Now please do a video of how to properly use the digital control panel...step by step THANKSWalter Hynsonhttps://www.blogger.com/profile/17491951067289432307noreply@blogger.comtag:blogger.com,1999:blog-247130680149573043.post-35734021207379770452019-11-10T06:51:51.111-08:002019-11-10T06:51:51.111-08:00This comment has been removed by a blog administrator.Alia parkerhttps://www.blogger.com/profile/02326303770549335930noreply@blogger.com