300 watt dual tube, both tubes not firing at same time

I bought a 4’ x 8’ 300 watt laser 2 years ago, The tube was broken by an accident in the shop. I purchased a new 300 watt dual tube, installed it, aligned it. The machine will cut but not with both tubes at once. The top tube will file sometimes, the bottom tube sometimes on a rare occasion both tubes fire and it is like the skys opened and the beam cuts great. one tube at a time will fire 58mA whenb both fire it is about 18mA. I have tried wiring CN6 to one power supply and CN7 to the other, the machime was originally looped between the 2 power supplies. I have been messing with this for about 6 months now. Very frustrated. So to re cap. New 300 watt dual tube, 2 new 150 watt power supplies and a new Rudia 6334M controller. Any help would be great.

Did you follow the Ruida diagrams for wiring the separate supplies…?

Don’t have a clue how this would be wired…

How does one mA meter measure both tubes… you have to clarify what this means or at least, how it works.

The Ruida can control two tubes, but the manuals usually show them suffixed as 1 or 2 in the connections… such as WP1 and WP2

Here is a diagram from my Ruida 6332G manual… rdc6332g.pdf.txt (2.9 MB)


Yes, that is how it is wired, but both tubes do not fire at the same time, its weird. One tube will fire, next cut sometimes the other tube will fire. on occasion both will fire. It will cut 1’’ acrylic in one pass so I assume both tubes are firing. I just do not see the beam thru the tube, I don’t know if I should see the beam in both tubes.

You can’t see the actual beam, but you can see the pink color ionized gasses.

They should look similar when they lase…

How is the mA meter wired into this?

You need to read each tube with it’s own meter to know what the tube is drawing.


The tubes do not look similar whan cutting, one tube will be a bright red where as the other just looks like clear glass. The mA readings show the same from each power supply. But I have trouble cutting they 1/2’’ acrylic.

Could you post a photo?


It doesn’t look like it’s lasing.

I don’t have a dual setup, but does it have some kind of lps for each tube?

Does the non lasing tube in the photo work by itself?

I know how the signals work, but don’t really have any experience with how to set a dual tube up.

If it’s been working and this is a hardware issue, maybe we can help, but we need more information on the machine…