What is the ampere meter used for?

[Edouard Connor]

Hello,
I have a little question,

i have used an 80w engraver for over two years with no problems, i had a cw-3000 cooler.

I produced a lot of things intensively.

In upgrades I often see the ampere meter, without really understanding the usefulness.

If someone can explain to me

[Gene Uselman]

mA meters measure the current to the glass tube- that is the definitive way to set your max power settings. There are max safe and max charts for the tube wattage if it is not on the tube itself. Better quality tubes have an [often handwritten] safe and max range on them. On my 130 tubes I normally run at 28 mA and up to 30 mA if I need more power [ the higher current breaks the tube down quicker ].

[Edouard Connor]

Ok I understand better, thank you for this explanation

[Gene Uselman]

The meters are cheap and very easy to install in the negative wire from the tube. They are very useful in our journey to be good laser operators.

[Edouard Connor]

I understand, I will do the necessary

[Johnny Smith]

This deleted by authors request.

Outcome: Well after a premature death of my 60W tube, I've replaced that with a RECI 100W tube at great expense and I've adjusted the power supply itself to deliver 80% of the maximum recommended mA.....Russ has a YouTube video about laser tube power versus mA basically saying that above 80% power you really don't see much gain at all....and my own experience reflects that also. At 80% max recommended power, I lost no speed at all when cutting.

Anyway, now when I set my controllers laser power to 100%, I know that my laser is actually being fired at no more than 80% of the manufacturers maximum recommended power for the tube thereby prolonging the life of the tube....I hope..my controller tells me the laser has been firing for a total of about 120 hours now!!. Most users would probably set the 100% power to equal 100% recommended mA, ie. 20mA if we take the above example (will be different for each brand/wattage of tube). After the very significant expense of replacing my tube, I'm now being somewhat conservative.

Hope this helps others.

[Gene Uselman]

Johnny- I am afraid that your first paragraph is faulty. You are mixing two types of CO2 tubes- almost all of ours are not PWM and should always be set to 20k freq- the current is varied by the program to produce different levels of power. I believe most PWM tubes are metal and rechargeable, but a few are glass and not rechargeable. Russ @ Sarbar Media has explored this quite thoroughly on Youtube.

[Johnny Smith]

Hi Gene, well if that's the case, I need to do some research to gain a proper understanding. In the meantime, how can my post be deleted (can't find an option for that or even an edit option) as I don't want anyone wasting their time on misinformation or worse doing something incorrectly to their laser that might have a negative effect.

[Gene Uselman]

Only board moderators can delete I believe, I handled this for you. I think the rest of the post is important as far as limiting your power in the power supply- I assume all modern power supplies have this feature and it would be good to let people know how to do this.