@Jason_Farrell That does look like what would be a ground. To verify disconnect it and measure its resistance to the FG pin on the front. If its 0 ohms then it is the same connection.
Your not a pain, these machines are 
Thanks a mil Don, will report back shortly
I just tried that and no laser when test button pressed. Had a look at the instructions and it says that blue cable is current return ?
Did you measure resistance between wire and FG as suggested above.
No Don sorry, I don’t have any equipment here . I will try to borrow a meter tomorrow
Hi again Don, measured across and got 0 . I have tried connecting it to chassis. No laser, left it hanging, no laser. If I connect it to the ammeter I can fire laser with test button but no reading on ammeter.
When I turn on main power button the 24v supply powers up but main PSU doesn’t. When I press laser on button the power supply turns on and the wp led lights up. Then when I press laser test button the wp led goes off and laser fires and laser led lights up.
The gantry does not reset though and when connected to laptop it says device not connected.
I checked and am getting 5v and 24v to the nano board. There is also a tl led on the main PSU but it never lights up.
Sorry, I’m prob not making any sense with my ramblings here !
@Jason_Farrell to make sure we are on the same page regarding the LPS (I will discuss the DC in next post), here is a summary of what you found:
-
FG and the blue wire read zero ohms. They are connected together!
-
If you connect the blue wire to the meter. [I assume the other side of the meter is connected to the lasers cathode]. The laser fires but meter reads nothing.
-
If you connect the meter to FG. [I assume the other side of the meter is connected to the lasers cathode]. The laser does not fire.
3 does not make sense if #1 is true.
…
I wonder if the meter is connected backward and the needle is moving to the left into its stops and therefore looks like it is not moving?
This still doesn’t explain why connecting to FG vs the blue wire does not allow the laser to fire?
…
If you look carefully on the back of the meter there is a “-” and “+” molded into the plastic. I had to use a flashlight to see mine.
A. The blue wire should be connected to “-”.
A.1: After connecting it this way measure the resistance from “-” on the meter to FG and post results.
A.2: If the blue wire was connected correctly post that … if so I’m temporarily stumped.
…
Here is how mine is connected.
@Jason_Farrell from your post above (you can reference answers by letter designation):
" When I turn on main power button the 24v supply powers up but main PSU doesn’t."
B.1: What are you calling the main PSU and how do you know its not powering up?
“When I press laser on button the power supply turns on and the wp led lights up. Then when I press laser test button the wp led goes off and laser fires and laser led lights up.”
B.2: What is WP? Post picture
B.3: What is the laser led. Post picture.
"The gantry does not reset though and when connected to laptop it says device not connected.
I checked and am getting 5v and 24v to the nano board. "
B.4: Are you measuring the 5V and 24V across the nano’s connector. I.E. probing ground on that connector to each of the voltages on that connector.
"There is also a tl led on the main PSU but it never lights up. "
B.4 What is the tl. Post picture
B.5: Post picture of control panel.
Hi again Don , sorry I was away with work. Back to annoy you again lol. By main PSU I mean the new one I bought. The large black one for the laser. I am attaching pictures, if you notice on bottom left there are 2 holes marked TL and WP. When I press laser switch on control panel the WP lights up. Then on the bottom right of picture there is another led marked laser, When I press laser test on control panel the laser led lights and the WP led dims. Hopefully you can see that from the photos. I also checked on the nano board and it is getting 5v and 24v
@Jason_Farrell so we can make sure we are on the same page can you verify my understandings above and answer the questions. Please index your answers using the # and letters as identifiers in your answer. That way we can tackle these one at a time.
Will do Don , thank you.
B1 - main PSU being the new large black replacement. The fan inside is coming on but no LED’s lighting.
B2- wp is an led on the power supply as in photo.
B3- laser is another led to the bottom right of the power supply.
B4- I measured on the board itself using ground on the board and 5v and 24v and getting voltage ok .
B5- tl is another led on power supply. Directly beside wp led. Shown in photo.
@Jason_Farrell ok good its a standard K40. Pls look further up this thread there are #'d and A questions :).
Ok lets do this one problem/symptom at a time.
please answer these using the #'s as reference
power on the machine
- When you push the red test button on the power supply does the laser fire (i.e. lights up)?
- If the laser fires, does the current meter show current?
Hi again don, yes to both of those questions now. I have wire from cathode going to + on ammeter and blue wire from rear of power supply going to - on ammeter. Laser powers up fine now and test fires and shows current on ammeter and adjusts using the knob on control board.
Problem now is gantry not resetting when laser is powered on
I used the meter on the board and using ground on the board I’m getting 5v and 24v and on the last pin marked lo I’m getting 4.96v
I’m wondering if its a ground issue. I have taken ground from my mains cable in. If I connect to chassis also the laser won’t power up or fire . also the max reading on the ammeter is 12ma at full power