Laser Power Supply (LPSU) Output Current Test Procedure

Laser Power Supply (LPSU) Output Current Test Procedure

Preface: This is a diagnostic procedure to collect data on the output of the LPSU. It is not necessary to perform this unless instructed to do so by Thunder Laser USA Support & Innovation Labs. But you can if you like. This instruction is specific to the Thunder Laser USA Nova series machines only.


Please reply back to your support ticket with your results                                                                                                                                                    


The Procedure:

This procedure runs the Lightburn file and allows you to view the LPSU ammeter to record the ma output values at the LPSU. The job will pulse at 10% and pause briefly and then pulse at 20% and pause, and so on up to 100%. While the machine is outputting, the operator should be recording the values from the power supply output.

Your laser will fire during this test. It is recommended to lower the bed down and clear the bed from any materials. Position the laser head so that it is not going to burn anything below it.



Step 1: Download the attached Lightburn file

Two versions are included, both in Lightburn formats LBRN2 and the legacy LBRN format. They were updated in Lightburn 1.12.01.

The file should be run as-is, without modifications. It utilizes advance features to create the desired output.
You should run the file with the Default Optimization settings ON and as shown:



The key is to have "Order By Layer" as the top priority. The other sliders down below do not really affect it.



Your Lightburn Preview should look like this:

or this

Step 2: Locate Power Supply for your machine

Nova 35, 51, and 63

Located on the back of the machine, behind the blue door to the Left of the exhaust outlet



Nova 24:

Located on the left side of your machine behind the lower blue door.




Step 3: Send and Run Job

Get your pen and paper ready. It would be good to make a column for 10-100% power in increments of 10 so that you will be ready to capture the output ma values.

Send the job down to the machine and run the job like you would run a normal job. Record the results and email them back to your ticket.

Video Run Through:


Using the provided test file attached at the end of this article. Here is an overview of the test file.




Here is how the meter should respond to the test file. Please record the mA value of each pulse in order from 10% to 100%



These resources show our mA meter on the laser near the e-stop button which is an aftermarket modification


Recommended Tube Current Limits:


Tube Wattage
Starting Current milliamps (ma)
Nominal Peak milliamps (ma)
Max milliamps (ma)
40 watt
5 ma
18 ma
20 ma
60 watt
5 ma
18 ma
20 ma
80 watt

24 ma
28 ma
100 watt
5 ma
24 ma
25 ma
130 watt
6 ma
28 ma
30 ma


Sample Results:









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