OMTech AF2435 not firing at rated power

LightBurn Hardware Compatibility
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I’m wondering if anyone has any suggestions here…

I’m running a few test jobs on my shiny new OMTech AF2435 via Lightburn (obviously). (This is a replacement for an FSL Pro24x36). However, it doesn’t appear I am getting the full rated power (80W) out of my tube… No matter what I try, I can’t get the meter to show any more than 6ma. The OMTech manual indicates I should be able to get at least 23ma through the 80W tube.

A simple Lightburn test file is set up to cut a box with a circle inside at 5mm/sec at a power rating of 95%. This gets transmitted to the AF2435 without issue and the drawing shows up on the Ruida RDC6442G-SH panel as expected. The drawing on the panel confirms the lines are to be cut at 95%.

I have the Min settings on the Ruida set to 10% and the Max settings at 95% so I don’t expect any throttling due to global configuration options on the controller.

When I run the job, the little power panel varies between 5ma and 6ma. The manual power knob is turned fully clockwise (to max). I can confirm the knob is working as when I rotate it fully counter-clockwise (to min) I can see the beam extinguish and power fall to 0ma.

Yes, I already have a message in to OMTech, but I’m wondering if anyone can think of anything I might be missing…

Thanks in advance…

2

In all likelihood you have your start speed down around the 5mm/s so you won’t get anything more than minimum power…

You can check it quickly by setting both Minimum and Maximum to a value, I’d use something less than 95% and re run it.

You can also look in the controller Edit → device settings and check for the start speed…

I scratched this together… When you are at or below the start speed, it will deliver only minimum power.

start-speed-power-transparent
start-speed-power-transparent1119×628 38.7 KB

Hope this is it…

:smile_cat:

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Yup! That was it! Thanks! (I tried to reply yesterday but apparently I’m “oversharing” as a new user - had to wait until today…)

Not sure why OMTech is shipping their Ruida controllers with a start speed of 8mm/sec while publishing Acrylic cutting recommendations (specifically for 80W) like this:

 3mm:   23ma @ 12mm/sec
 5mm:   23ma @ 5mm/sec
10mm:  23ma @ 2mm/sec
15mm:  23ma @ 1mm/sec
20mm:  23ma @ 0.7 mm/sec

There is just no way to get down to those speeds with the way they have the controller set.

Also, the numbers don’t appear to be correct (too slow) as my 5mm acrylic test cuts appear to work just fine using 14mm/sec (23ma)…

But Thanks!

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If you are not aware of these settings, they can ‘burn’ you… :crazy_face:

Where did you get the 23mA current limit?

My chart says 25mA operating current… so you’re in the ballpark…

Glad you got it going… I doubt that the people who set yours up really has a clue anyway…

I found my stepper motors were too hot to hold on to and found they had the motor driver set to 2X the current the stepper should have had. I corrected the driver, not it run warm… :exploding_head:

Have fun…

:smile_cat:

5

Yeah, you are right. They specifically suggest a 23ma max operating current in their cut tables. To me that’s my current “limit”. I understand the tube can accept more…

The numbers come out of their operating manual (for what its worth).

I tried to attached the two relevant manuals if you are interested. (Apparently I can’t upload PDF’s) One was included with the machine (I scanned it in) and the other I just downloaded from their web site. The manuals are different, but the cut tables for Acrylic are basically the same. (Which both seem unecessarily slow)

The “Web” manual shows 23ma (their suggested max operating power) to represent 70% power (100% = 28ma). The “Machine” manual says 23ma is 80% (100% = 30ma).

My FSL Laser had none of this… (and its software no longer works properly anyway). Anyway, what I have done is set the controller max power limit to 99% (it won’t take 100%) and then used the rotary dial to adjust the power at 23ma. This should give me a full/safe operating range with 100% being my personal operating limit. I understand I could also set the controller max power to 70% and then adjust for 23ma, but 100% seems much more natural moving forward. IOW: The power percentage is referenced to MY personal operating limit…

Am I setting myself up for more confusion down the road? This just seems more natural to me…

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You’ve seen the limits, if you’ve tried… What we usually do is add a txt extension x.pdf → x.pdf.txt then it will upload… The user can remove the .txt extension…

The other limit is 4mB in size. If you need to post a video or something larger. You can put it on your google drive or something similar and post a link… Don’t forget to allow anyone with the link to read it…

Where is this dial?

The way I was told to set it up was to send a 50% power to it and adjust the lps for 50% of the max power limit. This will allow full range of percentage power and synchronize with Lightburn percent power…

That’s why I wonder about the dial… Until I understand how this is wired up, I can’t really comment on your setup for power levels…

I do/did run my previous tube hot, chiller was set to 25C and I set the lps for 100% equaled to the max operating current … I run 70% - 90% power a lot when I cut… I knew when I set it up for cooling that it would probably limit tube life…

However I disagree with your logic … assuming 30mA as the manufacturers maximum.

If you ran it at 27mA that is 10% below what the maximum is or 90% power.

If you run it at 24mA that’s 20% below the maximum or 80%… that’s quite a safety range…

The bummer is that the tube will die without use, just time itself degrades them…

You have to pick…

Good luck

:smile_cat:

7

OK, Here you go. Too big to attach in any case. Put them up on one of my servers:

OMTech AF2435 80W (From web)

OMTech AF2435 80W (inc with machine)

The specific power ratings (ma vs percentages) is listed in both the above manuals. From my understanding, it’s not strictly a linear relationship (ma vs %Pwr). IOW: I don’t think you can simply take 20% off the 100% power rating (ma) and assume its 80%… I guess it comes down to the relationship between Electrical Power and Beam Power.

Check page 18 on the manual included with the machine and note that the values are slightly different in the power table in the other document.

The rotary dial on my laser is located on the left side. It’s some sort of an attenuator which allows manual control of the power going to the tube. This apparently sits between the controller and the laser. So even if I send a job at 100% and set my controller to allow 100% (99% actually) I can actually turn down the manual adjustment to ANY power value I want. By doing this, I can effectively define 100% to be anything I want (like 23ma). This way, I can set a job to cut at “100%”, set my controller to allow 100% (99% actually), and make it all correspond with “100%” of what I deem to be my personal operating maximum = 23ma (rather than the ACTUAL 100% of tube capacity).

The attenuation knob does allow full attenuation (all the way down to fully off). I can rotate the knob while a job is running and watch the beam fade and extinguish and then bring it back up again. So I set a test job to run at 100%, have my controller set to allow 100% (99%), and then just adjust the knob until I see 23ma (per the tables). Done.

The only downside I see here is if the knob somehow gets tweaked by mistake. I’m looking at 3D printing a fixture to hold the knob at my desired set point so it isn’t subject to being disturbed by mistake. Unless my adjustment gets tweaked, there is no way my machine will ever run at anything higher than 23ma.

Curiously, neither manual discusses what the meter/knob is called or how it should be used. But it definitely does provide manual control of the beam power and it will scale the power accordingly (as indicated by both the power meter and the beam intensity itself)

If you look at page 4 on the manual from the web, you can just make it out in the top photo on the upper left side of the machine.

It seems more natural for me to be able to work with cutting powers which scale to 100% (instead of limiting just to 70% or 80%). I’m confident I’m getting a power I can feel comfortable with (23ma when I request 100%). It’s just a matter of whether some other considerations further down the road (like conflicting with community traditions) will change my opinion on this…

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I guess a simplified question might be:

  • Why set your 100% to be the 100% actual tube rating (30ma in my case)? Particularly if you don’t ever want to run it that high…

  • Why not set your 100% to equal 100% of what you feel is your personal max/safe desired operating power (23ma in my case)?

Maybe the knob on my unit just makes this that much easier to manage…

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What I was trying to explain, was if you set it up the lps for whatever maximum you want to have, say 23mA, then your 100% setting in Lightburn will relate to 23mA…

That is all…

Tubes are not linear, but they are not that far off, there is a slight curve, but it’s pretty negligible.

Have fun…

:smile_cat:

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Thats precisely what I am doing. Thanks…

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