100 Watt Text Engraving

I just got a new 100 watt Omtech machine. I finished aligning the mirrors and ran a material test. I’m using the Omtech test card. I had set the text engraving at a speed of 200mms and power at 18% per the manual. This was my starting point. The laser blew through 3mm baltic birch. I adjusted to speed of 300, power 15%, blew through again. There were a few more tries in between and finally tried 600mms, 10%power. The laser still cut through.

Any suggestions?

Thanks!

Dale

Do you have a mA reading at 10% or any of the other settings?

Are you sure you’re setup for mm/s?

:smile_cat:

at 10% power, LPS reads 11Ma. Yes, machine set to mm/s. Omtech manual says it should be 2Ma at 10% power.

Dale

I should add that Omtech asked me to measure voltage between G and IN terminals on the LPS while running at 10% powe. It measured .499 volts.

They feel its not the controller but offered no other possibilities.

Dale

The HV power supply is the obvious candidate, because the controller is providing the correct PWM signal at 10%.

Despite being a new machine, it arrived with a defective power supply. Get a warranty claim started now and be prepared to take that discussion to the mat.

1 Like

Thanks Ed, I was thinking along the same line

Dale

Hey Ed,

Where is the HV power supply? What does it look like? I can’t find in the manual diagrams or the machine.

Thanks!

Dale

Never mind. It’s part of the laser power supply. This unit needs to be replaced?

On My 100 Watt OMTECT the High Voltage is located on the Left Side.

I believe it’s part of the laser power supply

:smile_cat:

Depends on the machine layout, but you’re looking for a classic Black Box:

It’ll have a fat red wire to the tube anode and a skinny black wire from the tube cathode.

The green connectors should be unplug / swap supplies / plug and you’re done.

Thanks Jack,

Are the 2 terminals you’ve enclosed in a red rectangle for test? Ed thinks it’s the HV side of the LPS. We’ll see what Omtech thinks.

Dale

It’s likely the lps. The two boxed connectors are 1. generic and used for picking signals, the other is the L-On1 that enables it to lase.

:smile_cat:

Thanks Jack!

Hey Ed,

Wow, trying to deal with Omtech tech support via email is likke trying to mate elephants; the time difference from China only complicates the process. But, I finally got on the phone with them in Anaheim and after 5 minutes, my problem was resolved. They’re sending me a new LPS.

Thanks for your help, again!

Dale

Excellent!

It should have the chunky HV connector on the anode wire, so you can swap supplies with just a twist.

The cathode lead in my laser sported a crudely twisted connection “insulated” with electrical tape. While that was OK-ish for a wire operating near ground potential, I installed a crimped quick-disconnect fitting (similar to those) to simplify The Next Time.

I’m afraid, I’m still having a problem. After I installed the new LPS, I ran a few tests at different power levels and everything seemed to be OK. So, I started an engraving project, the image came out great but when I ran the cut layer,1/4" baltic birch, speed 7, power 28%, it didn’t come close to cutting. The mA meter read 2-3mA, much lower than expected. So, I checked my mirrors which were previously aligned properly and a pulse would not fire.

I’m thinking it has something to do with the 6 pin terminal block. I disconnected it from the LPS a pressed the red test button and it blew through the tape. Reconnected it after checking connections and still have the same problems.

Thoughts?

Dale

Those two are not connected at all: the mirrors have no effect on the tube current.

That’s expected. The doc is nonexistent, but word has it the supply will fire the tube at either half or full power, either of which would punch through paper.

Your would not be the first machine to be badly wired. Scrape off the snot over the wires / ferrules, take each one out, and make sure the wire conductor actually makes contact with the metal terminal.

We’ve seen a machine where the terminal block was missing its guts and another where the wire insulation was badly stripped, so anything is possible.

Then do the same thing on the other end of those wires at the controller.

Then measure the resistance between the ends of each wire. If it isn’t pretty close to zero, that’s a problem.

Beyond that, you’ve measured all the relevant parts, so it’s a real puzzle.

Well, just spoke with OMTech and they are sending me a new controller and a new 100 watt tube. All of 5his plus the LPS they sent me. This is a new machine! Unbelievable!