Hi everyone. My OMTech K40 came today. It came with a large hollow ceramic resistor and instructions o. How to disconnect the power to connect to resistor so you can test the power supply. Out of all the reading and videos I’ve watched, i have never seen this. Anyone here? It doesn’t say if this needs to be done before setting up the laser or only if there is a problem. Im assuming its to troubleshoot if there is a problem. Thanks for any help.
I recall somewhere that a resistor was used in the Anode to test the supply [arching?]. I do not remember where it was that I saw it and how it was used? It was for troubleshooting the LPS.
I would never recommend messing with the anode side of a CO2 laser its deadly. We have been pretty successful diagnosing bad LPS by process of elimination.
- Can you tell me what the resistance of the resistor is?
- Can you post the instructions?
- Please post a picture of the resistor.
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Sounds like a “dummy load”. Places a load on the power supply to simulate a power draw for testing.
OMTech of one of the companies has a video on using the resistor… I think it just replaces the tube… I can’t remember, but I think, it’s basically a dummy load as @Strider_Matic stated.
It’s a rather large marge as 30,000V @ 20mA is 6kW of power it has to dissipate… don’t test it long periods… 
If @BigKen could post the instructions that would be nice…
I suspect it isn’t going to tell you much.
I have a high voltage meter on my machine and I can see little difference when I had a tube go out of TEM00 state… no real indication in either current or voltage.
Good spot to say listen to @donkjr he’s been pretty intimate with these lps …
An lps can have high voltage present for hours after they are used. They are high impedance supplies with no resistance to drain off the high voltage.
