Coherent K250 Control Pinout Please Help!

A place for users to ask questions and search for already asked questions. "BE NICE" and helpful!
Post Reply
Stephen Lynch
Posts: 14
Joined: Fri Aug 24, 2018
Location: Gainesville Ga.
Country: United States
Nickname: Steve
Laser Machine Make or Type: Robotec 4x8 dual head (400 / 100), Chinese 60 watt
Laser Power: 400
Laser Bed Size: 56 x 100
Home Position: BL
RDWorks Version: 8.01.21
Windows Version: 10
Accessories: Live Focus, Rotary, Z up / Down

Hey all! I'm absolutely at wit's end. I have A coherent K250 RF C02 laser system and I have everything ready to go with new Ruida RDC6445G, and height controller, and I have one small problem. I cannot get the pinout to control the laser.

Coherent are being absolute wankers. I've contacted Coherent in 3 different countries, and no one will provide me with the info. I can find nothing online.. I've been searching for upwards of 8 months. I'be tried to contact youtubers, I've messaged 8-10 year old posts on various forums, and even used language translators to try to communicate with people in other countries.

I'm incredibly deflated right now, As I'm staring at a beautiful laser with decades of life left in it, and I cannot fire it.

The pinout in question, is the DB25 connector on he back of the D64/84 RF module. I believe I need maybe 4 possibly 6 pins total, and Even after opening the unit, I cannot determine what pins do what.

If you know someone who uses this laser, or if you know it, I implore you. Please help me get in touch with someone who can provide this basic info.

I'm willing to pay if I have to.

I just don't know how much more of this torture I can take. :lol:

Thanks so much for your consideration.
User avatar
Gene Uselman
Posts: 2180
Joined: Thu Jul 07, 2016
Location: Suburban Minneapolis, Minnesota, US
Country: USA
Nickname: Gene
Laser Machine Make or Type: QC
Laser Power: 130W
Laser Bed Size: 900x1300
Home Position: TR
Control Software: LIGHTBURN
RDWorks Version: RDw .19 & Lightburn
LightBurn Version: Latest
Ruida Controller: RDC6442
Windows Version: Win 10 Pro
Accessories: I have a combining lenses, pin tables [homebuilt], honeycomb tables , wireless remote, Modifed Ultimate Air Assist, home built non-powered rotary device, PrusaMK4 and Mini Prusa printers.

That sounds like an interesting machine. I am not sure that we have any RF laser members- Russ was experimenting with an RF laser 'tube' but I did not really follow along this those videos as I have plenty of problems with the glass tubes. These people advertise repairs on the tubes so I would think that they might have some info? I am sure you know that the RF signal will be different from what we use. Good luck, it can be very frustrating finding people with this specialized knowledge.

https://www.radwell.com/en-US/Buy/COHER ... V-84%20RF/
If the Help and advice you received here was of VALUE...
Please consider making a donation to maintain the RDWORKSLAB Forum.



The days that I keep my gratitude higher than
my expectations, Well, I have really good days.

Ray Wylie Hubbard- unfortunately deceased
Stephen Lynch
Posts: 14
Joined: Fri Aug 24, 2018
Location: Gainesville Ga.
Country: United States
Nickname: Steve
Laser Machine Make or Type: Robotec 4x8 dual head (400 / 100), Chinese 60 watt
Laser Power: 400
Laser Bed Size: 56 x 100
Home Position: BL
RDWorks Version: 8.01.21
Windows Version: 10
Accessories: Live Focus, Rotary, Z up / Down

Thanks Gene!

It's not My first foray into RF, just my first "Big One". They're actually pretty much the same as wiring up a little diode laser. Not much different than a glass tube either. (Laser Enable, and Laser PWM)

The main difference, is that although they're still a CO2 laser tube, the PWM frequency is adjustable. If you leave it set at 20Khz, it'll behave just like a glass tube, but if you want to dial it in more specifically for metals, glass, different plastics, or even different types of woods, you can. its very helpful for getting a much more precisely tuned beam. That's an extra layer of parameters I guess, but nothing you can't sort out pretty quickly with some test cuts.

I promise you, you know more about running an RF laser than you think! Especially if you've ever run a fiber laser!

I obtained this laser source through an international used machine broker for $3000. it's a discontinued Coherent product, but for all intents and purposes, it should still have a good 20 years of service left in it, as you can recharge the tube when it needs it. It was plucked from an obsoleted HAAS machine.
It took almost 9 months to get to me because of a multitude of customs, and regulatory issues, spread across 3 countries.
I started to think I'd never get it released.

Because the chances of me acquiring such an expensive laser source for a reasonable price twice, is probably next to impossible, I'm extremely worried about damaging the RF AMP. If I screw it up, just the amp alone is about $15000.00 for a refurbished one, which would mean "Project terminated".

I've got my 380V conditioned 3 phase power sorted, My 200 amp 48V DC, My cooling, mechanical shutter, Interlock, motion control... Everything else is ready!
Normally I'd be open to making some educated guesses, but this is probably My one opportunity to be able to have a laser of this caliber, so I'm not going to get impatient, and do something dumb to let the smoke out of it.
I've waited literally almost 2 years to have all of the pieces of the puzzle come together, and as much as it's killing me, I'm going to just have to keep beating the bushes, looking for the final bit of info necessary to fire this thing up.

I've had some pretty cool side conversations with some very interesting people I met through this forum, so I hoped maybe, just maybe, someone knew a guy, who knew a guy... lol

Thanks for the Radwell suggestion.
I've dealt with them before, and I'll give them a holler!
Post Reply

Return to “User Questions and Help”