I have a K40 laser, which stopped burning half way through a job.

Lasers
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1

I have a K40 laser, which stopped burning half way through a job. The cnc part of the machine is working perfect, but the tube isn’t firing. I replaced the tube, but still nothing. Has anyone any idea what could be the fault. Any help would be greatly appreciated.
Thanks… Stevie

2

The circuit goes as follows as I understand it

PSU Supplies HV to tube
WHEN
the laser switch makes contact (is depressed)
AND
the power Pot is turned to a value (usually 4 ma or over) that causes the tube to lase.

Therefore
either PSU is not supply HV
OR
Laser switch is not making contact
OR
Pot is faulty

given your symptoms ie: stopped in middle of a job I’m betting on the PSU being FUBAR

You can test the laser switch with an ohm meter and the unit off
you can also test the pot with an ohm meter and the unit off

DO NOT TRY to test the HV unless you know what your doing - the consequences could be lethal

Hope that helps

3

Thanks greg

4

Do you have any other safety switches, water flow, lid switch ect… If they went bad and opened your circuit that will stop your tube from firing also.

5

No I don’t have any other safety switches Rick.