C3D - Laser tube always on

Machine: Bought 50W CO2 Laser with M2 Nano.
Board: replaced with C3D Laserboard

Firmware: Smoothie latest version (already updated)

Problem/ Question: I completely disassambled the original laser machine and put it into a way larger case. I use the C3D supplied 24V 5A PSU and disconnected the 24V and 5V coming from the laser psu. I removed the movable Z-Table since its crap. The case is grounded to the wall-outlet-ground. Steppermotors work perfectly. Everything is fine, except:

I turn on the laserboard, then the laser psu. Light, water- and air-pump working fine. Digital Potentiometer is up and set to 8mA. Laser Indicator LED is on. Laser starts firing after 3seconds with what is set on the display. This should not happen!

diagnosis so far:
5 and 6 are shorted: laser fires. I immediately turn off the machine or set the pot to 0mA.
5 and 6 are disconnected: laser doesnt fire on start. “Test fire” works with digital pot. In this case the laser won’t fire the signal from the laserboard.
5 to 11 are disconnected (dig. pot): laser immediately on 100% (dangerous for tube, output way too high).
I disconnected the laserboard with the same results as above.

I tried to connect 10 & 11 and connect 9 with the laser board output as supposed here:

Result: Laser 100% on.

I might have damaged the psu in trying different setups. I think the psu should not automatically fire the tube on start, only when receiving a signal.

Is my wiring correct? I think I need to rewire the dig Pot in some way, but honestly i don’t know how. This guy got it figured out, but I fail on applying the idea:

Anyone can help or had the same issue?

Thank you in advance!

This is the the digital potentiometer:

This is the PSU:

Can anyone recommend a replacement/upgrade PSU?
Ultimately I want to use a 90W Reci W2 tube, since it has lots of power and is way cheaper than 100W tubes. Is there a PSU that can handle the current tube AND the 90W tube?

I removed the short of pin 5 and 6 and everything seems to work. When I add a closure safety switch, it won’t work. I expect the psu to be corrupt for this function (?).

I now made a few cutting tests with 8-12% of max. Power Level and the PSU makes crackling noises. wtf --> Whats going on here?

I can’t read the current, only percentage of power (in the start post i wrote mA, which is wrong, it’s %).

The C3D Mini and the LaserBoard are different - that large plug is flipped.

Read the legend on the board (both front and back) and see this image for the correct pinout:


If you disconnect the large plug from the board and touch L and Gnd together, the laser should fire. This replicates how the board “talks to” the LPSU but removes the board from the equation so that you can resolve your issues such as the crackling. Seriously - fix that. You might have an arc happening.
If you have the plug disconnected and L and Gnd not connected, the laser should never fire.

Digital panels suck, read this:

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