2.x Laser Build, LPS output will not turn off after the cmd to turn on is sent.

I had forgotten about the halmeter.

It sees the following on pin 7 while the test file is running - and nothing when not running:

freq: 50
duty cycle: true
freq speed: -50
magic z: true
master: true
power cmd: 100
pwm: true

I was thinking about the problem this morning and decided to test voltage on all of the output pins on the BOB in each state. The test showed that only pin 7 was misbehaving at a low level voltage. I swapped to unused pin 6 and updated that .hal file and... it works:) I am doing the tube upgrade because my coolant flow switch had stuck open - and my chiller had failed to turn on, resulting in a cracked tube while running a job (thankfully it had a few thousand hours on it so no big loss) - I am guessing that I got a high voltage short through the tube to laser DC ground, resulting in the damaged control pin on the BOB. Now I am really glad that I never put that DC neg to AC earth jumper in - I am sure it would have resulted in more damaged equipment. I will order a extra V-5 BOB just in case it ever needs to be swapped.

Thanks for all of your help Andy, you guided me in the right direction.

I am still setting up PWM control for pin 6, so not done yet. I may have a few more questions.

Thanks Andy,

Now I cannot get the LPS to come up to full power. I have adjusted the max DC and scale to higher levels, using S10000 just to be sure. When firing my multimeter reads almost 5vdc on the TTL high pin input to the LPS.

Because the voltage on the pin looks higher then it needs to be (by a long shot) to reach full power I suspect the power supply is not interpreting the PWM signal properly.

I seem to remember that 2.x laser was intended to be used with cheap power supplies without a TTL input? If this is correct then I should just switch to analog input (and adjust max output), but will it still operate as PWM?

Never mind:)

I found the original LPS info here:
www.buildlog.net/cnc_laser/buildlog_2.html

And realized that I had forgotten how the LSP was controlled with a trigger and signal, I had disconnected the trigger pin (thinking it was a manual fire control) while troubleshooting.

It is all hooked back up properly and working well at full power, turning off properly and is now wired fail safe (which I am very happy about).

I need to mess around with PPI, I noticed though all of my troubleshooting/firing that I am not getting optimal power density.

Thanks for all of your time Andy. Hopefully this post helps someone else out who forgot how to wire the LPS control:)

The files for it are here:

github.com/bjj/2x_laser

Site is here:
buildlog.net

Relevant paper regarding the basis of PPI/M control is here:
www.buildlog.net/blog/2011/12/getting-mo...-built-laser-system/

Its an old opensource laser project. My laser is based on the same control software although I use completely different hardware and have a bed size of 48"x72" - with the new 130W tube. I have considered changing to a updated control system such as a DSP but I love this one and it works very smoothly in my workflow.

This laser allowed me to take a part time business full time and move off grid:) I owe alot of credit to buildlog and people like you - helping along the way, this has literally changed my life. Thank you, Travis.