How to Test and Set a Chinese (China) Made CO2 Laser Power Supply to Get Long Life From Your CO2 Laser Tube for Your Laser Engraving and Laser Cutting Machine System

Introduction: How to Test and Set a Chinese (China) Made CO2 Laser Power Supply to Get Long Life From Your CO2 Laser Tube for Your Laser Engraving and Laser Cutting Machine System

Be safe when performing this project.

SAFETY IS MOST IMPORTANT.  IF YOU DO IT WRONG THEN YOU CAN BE ELECTROCUTED.  THE HIGH VOLTAGE AND POWER COMBINATION CAN BE LETHAL.  FOLLOW THE INSTRUCTIONS BELOW. DO NOT DEVIATE FROM THE INSTRUCTIONS REGARDING SAFETY.

The high voltage laser power supply settings can greatly affect the lifetime of the CO2 glass laser tube.  A setting above 30 mA will, in almost all cases, greatly diminish the operational life (changing an expected life of several years to months).  Even though the laser tubes are ranked in months, such as the 60 watt tubes, I have had customers use them for years before they finally loose power.

More recently, the higher power CO2 glass laser tubes, above 80 watts, and certainly 100, 130, 150, and 180 watts have been more inclined to have shortened lives because the power supply is improperly set.  For example, I had an unscrupulous seller who sold me a 150 watt laser with a power supply set at 34 mA.  My Mahoney laser power probe measured 145 watts.  Then, I contacted the seller because my multimeter read 34 mA.  His engineer said the power supply should be set to 30 mA for full warranty on the tube.  After setting to 30 mA, I measured the laser output power and got 129 watts.  Then, I contacted the company and returned the laser because the seller had actually sold me a 130 watt laser with a 150 watt price tag.

Whatever your reason for checking the power supply current, the steps are provided to demonstrate a safe manner to take a reading then take action to remedy.

Step 1: Do Not Touch the Red Wire.

1. Power off laser machine
2. Wait ten minutes. this is the time for the power supply to drain power from its electrical capacitors. 
3. Setup as shown in photos below.  You will need to purchase and use two sets of wires.  We recommend a black wire with aligator clips on each end and a red wire with aligator clips on each end.  These wires should be available at radio shack.

          A. See the power supply wire connection.  Do not touch the red wire.  It has extremely high voltage that is lethal.

          B.  See the thin wire.  It is colored blue, or black, or green as shown.

Step 2: Insert Meter Wires to Measure Current (mA)

C. See the meter below as an example meter.  Some meters are slightly different, so adjust instructions as needed.  Set meter to read current at mA.  Set meter to read DC current.  Insert red cable of meter into meter connection for current (labeled mA, or micro A, or A).

Step 3: The Meter Reading Should Show the Proper Units (mA) and a Zero Value

Step 4: D. Disconnect Thin Wire (colored Blue or Black or Green) From the Laser.

Step 5: E. Connect Your Wire to the Laser (aligator Clip Is Useful on Return Wire).

Step 6: F. Connect Your New Wire to Meter Red Wire. Use an Electrical Insulator, Like the Wood Block Shown, to Support the Wire at the Connection.

Step 7: See the Solid Electrical Connection. See Its Location, in the Center of the Wood Insulator Plank.

Step 8: G. Connect the Thin Wire From the Power Supply (colored Blue/black/green) to the Black Wire of the Meter Using Your Wire (alligator Clips Are Useful).

Step 9: More Cable Connections Located in the Center of the Insulating Board

Step 10: Confirm Electrical Connections. Take Reading.

Check and confirm all connections and review these instructions.  After you confirm that all connections have been completed properly, then power on the laser machine. 

Using the touchpad, select Menu and set the laser power to 5% and the time to 3000 ms.  Power on the the laser from the touchpad and read the meter after the number settles.  To confirm that you have no problems, there will be no sparks or electrical arcing.  If sparks or electrical arcing then stop all work, power off the machine.

If the meter provides a reading and no sparks or arcing, then proceed by setting the laser power to 100%.

The current measurement at maximum output power should be 28 mA for a long life setting for a standard Chinese CO2 glass laser tube.  If the value is higher (such as more than 30 mA) then the internal gases will be consumed much more quickly during operation and the glass laser tube will need to be replaced more often.




Step 11: Adjusting the Potentiometer to Reduce Current

To adjust the current downward, consult your power supply manual.  DO NOT open the laser power supply enclosure and insert your fingers.  Using a grounding wire, ground everything when working on a power supply.  I was shocked six hours after power off, by touching the underside of the circuit card inside the laser power supply.  Always use a wire connected to ground to remove any lingering voltages stored in the capacitors inside the laser.  In many cases, the enclosure does not need to be opened and the potentiometer can be adjusted.

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33 Comments

0
jav266
jav266

9 months ago

Hello, I have a 130W DY20 laser power supply a reci tube, the laser was working fine, but suddenly the current drops to 4mA, how can I know if the problem is the tube or the power supply? Thanks for the help

0
Johnnywild2004
Johnnywild2004

Question 1 year ago

I have a hole with a potentiometer in the side of my hy-T80 laser power supply but when I asked the manufacturer they said not to touch, could anyone with a similar T model power supply weigh in or not if this is to adjust laser max power?

0
dellc2012
dellc2012

1 year ago

I have a 100W reci. My laser has been working fine on light use for 2 months. I rarely ever go above 55% power. Now I keep blowing fuses when I try to run it. Do I need a new Power supply?

0
strahinja.levic
strahinja.levic

1 year ago

I have a problem with my 1390 laser machine with 100w w4 reci tube (acc 700 eorking hours) It can cut acrylic 10mm in every corner on 95% power it is 22 mA. And even it can cut thick material engraving is very bad invisible in midle of the table and lower and right quadrant. My mirrors are aligned.

0
fono79
fono79

Reply 1 year ago

have you check you bed level?

0
ShailindraS
ShailindraS

Question 1 year ago

Hello i have a k40 laser engraver and now fire comming out but the beam light goes on when i put the power at 50%,70% but no fire

0
mbowie4
mbowie4

4 years ago

How much does the multimeter pull down the current? I notice the laser intensity fades when I have the meter in series downstream from the laser tube. This makes me think that the meter must have some resistance and that the current reading may not be entirely accurate. At full power my meter reads 23.6 mA. Should I assume that is accurate?

0
TanaseB
TanaseB

Reply 1 year ago

A good multimeter (fluke) 0.0001 ohm , a chinese one i dont know.

0
Csguillory
Csguillory

4 years ago

We have a Chinese Redsail cm1290 laser engraver. The laser PSU reads L33 when we press the test button. Does anyone have any clues what it means? Our laser will not fire?

0
alvin198721
alvin198721

Reply 1 year ago

Check your cheller connection sensor

0
Veronica MorilloP
Veronica MorilloP

Reply 3 years ago

Esta disparando 33 mA. Acorta la vida del tubo.

0
firmandi.sy
firmandi.sy

Question 2 years ago

I have a problem with my laser power. no matter how I set the laser power, the laser beam that comes out is no different. even though I am setting the power 2% the laser beam that comes out is still like 25% power.
can you tell what happened?
Thank you.
0
alvin198721
alvin198721

Answer 1 year ago

Maybe u change your laser parameter setting accidentally in the touch pad of your machine, not in the computer must be set in zero

0
Gladcook
Gladcook

2 years ago

Hi
I have a 150W laser machine (Mixed laser) Chinese.Reci tube I cleaned tube and tube lens and now cant get any power from it .There is sufficient water going through but just sends out a ring of faint dots to the first mirror.
And ideas / help will be greatly appreciated
I also have a 90W Reci tube in a 6090 machine Chinese and this only send sout a constant beam strength regardless of the power settings from Software . About 30% consistantly for scanning or cutting.

0
zootalaws
zootalaws

Answer 2 years ago

Using a laser power probe designed for CO2 lasers, like a Mahoney power probe.

0
MarkW219
MarkW219

5 years ago

Hi have just set up my new 60w chinese laser cutter and thr interface on it is in chinese and when i try the pulse button nothing happens and error message comes up in chinese. Ther does not seem to be any pwer going through the laser tube not sure what to do next any ideas.

20160415_130733.jpg
0
laserspewpewpew
laserspewpewpew

Reply 3 years ago

Also, that looks like a Ruida-based controller. You can change the language by pressing the Z/U button then the down button several times until you are at the first option in the second column. Press Enter and then select a language.
(I'm sure you've figured this out by now, but this is as much for others who might just now be stumbling onto this question)