[texasinmi]

Guru's

Just got my K40 laser up and running but am having as issue. The power meter does not work and the knob to adjust it does nothing. Anyone else have this issue.

It is interesting that when I looked at Youtube on the K40, the unit that was being demoed had the same problem.

Thanks in advance.

Tex

[SignWave]

is it possible that the polarity is reversed?

[wmgeorge]

is it possible that the polarity is reversed?

I think he means polarity of the meter connections, and that is a good point. But does the tube actually fire? Danger, warning... the HV side is around 20,000 vdc enough to give you a good heart stopping zap.

[texasinmi]

Yes, the laser fires at full power.

Tex

[wmgeorge]

Try swapping the leads around on the mA meter if you have not already.

[cinematic2]

The power meter does not work and the knob to adjust it does nothing. Anyone else have this issue.

This is not a power meter. This is miliampmeter that shows how much current laser use.
If it do not work it just may be faulty.
If that was reversed you would see it knocking the wall :-)
Turn machine off and check if there is a conductivity from laser kathode (output side) to mAmp meter and than to Ground.
There must be Ground - Kathode connection in any way because laser fires but there may be a short or something.

[wmgeorge]

This is not a power meter. This is miliampmeter that shows how much current laser use.
If it do not work it just may be faulty.
If that was reversed you would see it knocking the wall :-)
Turn machine off and check if there is a conductivity from laser kathode (output side) to mAmp meter and than to Ground.
There must be Ground - Kathode connection in any way because laser fires but there may be a short or something.

The mA meter which indicates the power the tube is outputting must be good electrically because it is the path or return lead of the tube HV PS.. It the meter leads are reversed then the meter movement could be jammed up against the side and not moving at all. So if you reverse the leads, about a 30 second job you will know. It its not working replace the power meter Watts=E*I Amperage is an indication of power used.