Laser don't fire, HELP please!

[irresistiblecam]

Hi, I finally got a new K40 laser machine from ebay, but it doesn't work!

It have a damage on the steel case, on the left side, that should't compromise the funtionality.

I setup it, put the air pump into a water tank, etc...

When I switch on the machine  the red led of switch button and  power supply light on.

then I press the laser switch and the laser test button, but nothing happening.

I put some receipt paper on the mirror, but nothing fire up.

The amperemeter doesn't move.

I installed the software and connect the machine to PC, and start to engrave and cutting, the head moved corrected, but the laser not fire, not working.

How can I to solve the problem? Or make some tests?

[irresistiblecam]

The controller is Lihuiyu Studio Labs 6C6879-LASER-M2:6  FIREWARE VER: 2014.12.15

The software is CorelLaser 2013.02

Someone have recent revision?

I didn't connet the ground pin on the rear, just because I have a 3 pins 220V plug and a good ground connection in my apartment.

Some photos in attach..

[ajf]

Hi,

You should contact the seller, they should help you troubleshoot and supply replacement/parts if needed.  It's probably either a bad laser tube, power supply or bad wire/connection.  

regards,

aj

[irresistiblecam]

I already contact the seller, he is from germany. But no reply at moment.

How I could test if the problem is the tube or the power supply?

How could I use a tester, to check if power supply runs with correct current for the tube?

[Turnkey]

Please be careful when testing as it is a high voltage power supply. It can kill you.

Maybe turn the power control knob to maximum? The laser should fire when you press the test button. A red LED light on the power supply will illuminate when you press the test button.

[irresistiblecam]

this is the reason why I asked how I could use the tester.

I don't know what is the maximum for the power control. It don't have text or number. I just tested with the knob at the 2 extreme limit and at the middle.

The red led light on the power supply is aways on, even when don't pust the test button

[irresistiblecam]

this is the photo of power suply, where I could connect the 2 terminales of the tester to measure the Volt?

[ajf]

First, let me reiterate what Turnkey said: Be very careful! The power supply can kill you even if it's unplugged, because the capacitors will hold a charge for several hours.

You can't really test the voltage for the tube as it's unlikely you have a meter that could test 20+kV.  You can test the current, but that would be no different than what built in ammeter is showing (assuming it's working and the wiring is good.)

For what it's worth, there is a good guide for testing the tube current at Instructables.

Honestly, I'd recommend waiting for the seller to get back to you.  

However, if you want to do some troubleshooting right now, I'd say start by checking the wiring, connections and switches. Start by unplugging the machine from mains and then disconnect the three green terminal connectors from the PSU.  Then, remove the sheathing from the wires so you can get a better look. The connector on the left is for mains power and connects to the red toggle switch, the one on the far right is the low voltage supply for the logic board and Low Fire input, and the center one has the Intensity, High Fire and the safety interlock(s).  

It sounds like you are getting power to the logic board, so you probably want to focus on just the center connector and all the switches connected to it.  You will want to test continuity for the switches and also impedence on the potentiometer. 

Given the wide variety of how the K40s are setup, it's hard to be more specific.  For instance, I don't know if you have a water flow sensor or if there are interlocks on your build area cover.  

Again, please be very careful and stay away from the thick red wire from the PSU to the tube and the PSU in general.  Unless you really know what you are doing, there is a very high risk of injury or DEATH messing with the PSU and you really wouldn't be able to fix any fault.

regards,

aj

[Turnkey]

correction : your psu is a little different to mine, so your red led will always be turned on.

[Turnkey]

It sounds sort of like the interlock isn't working perhaps. If you have a multimeter you should check the continuity on the button labeled "Laser Switch". That button needs to be pressed down for the laser to fire so that's a closed condition. Check this all when the unit is unplugged from the wall.

Also check that it connects through on the green plug.

Also maximum power on the little dial is all the way to the right (clockwise)

[irresistiblecam]

I tested the laser switch button, and it is short circuit when down. so it is ok.

>Also check that it connects through on the green plug

I don't understand. Could you explain it? What is the green plug?

[ajf]

That's the terminal connector where all the wires connect to your PSU.  In this case, the laser switch connects to the center terminal on your PSU.