Power Supply

Machine: k40 - Orion Tech

Board: Cohesion 3d

Firmware: Smoothie

Problem/ Question:
I was watching this video:

At 9:30 he has the C3D Power Supply inside his case. And he says it is hooked up to mains. Does anyone do that here? I’d love to have just one switch to turn on the laser and C3D power.

Does anyone know how he has this wired? Or is everyone running the power supply outside the box and another cable plugged in?


In my K40, I chopped the NEMA1 connector off the end of the AC input cord on the power brick and spliced it in to the output of the power switch. I cut off the old spade connectors, put both pieces of wire into new (insulated!) connectors (making sure hot and neutral polarity were respected), and crimped them on. I routed the wires through the split tubing in parallel so everything looks nice.

If you’re not comfortable doing AC mains work, I wouldn’t suggest the above. The other alternative is to use a switched power strip with everything plugged into it and control power there instead.

I don’t mind doing mains work.

Did you use the barrel connector to the C3D and route it next to the USB connector?

I whacked the barrel connector off too and used the terminals in the corner labeled “separate power in 36V MAX” instead

Yes, I am sure several people have done it, but it is not something I recommend or support. If you have communications or stability issues the first thing we will tell you to do is to plug the power brick into its own outlet.

1 Like

Good to know. Thank you for your help, all.

I wouldn’t have a wall wart inside or outside the machine if you paid me. Why not do proper wiring like an actual machine? (“actual” herein defined as totally bereft of wall warts and not having 54 separate plugs to plug in, or barrel connectors). That’s not the way proper machines are done. The Laserboard has proper terminals for power input, that’s what they’re there for, and a separate power supply has better specs for ripple, line and load regulation, etc., than the stock power supply. Plus, if you don’t shitcan the stock wall wart, you’ll have it for temporary bench power for stuff you DON’T care about.

Don’t even get me started on barrel connectors. Why would anyone ever use a non-latching connector, especially on a device that has actual terminals?

All good thoughts, thank you.

In terms of power supplies, how would you handle things like 110v, how would you wire those up? I am thinking like my air pump (as I won’t run my compressor across the house).

Thank you!

I don’t know how everyone else does it, but I have two good quality power strips. One has “always on” things like my computer, monitor, etc. and the other has my laser, water pump, air pump, and exhaust fan. When I turn on the second power strip it turns on everything I need to run the laser.

The only changes I’ve made from that recently is that I’ve added an outlet with a relay to turn on the air pump via LightBurn when running a job.

(I used to build interactive museum exhibits, and inside every component’s access panel was a power strips with everything plugged into it. That was pretty much the “standard” for that industry.)

It appears that unless you place the brick inside your power supply / controller board compartment and connect it to the output of switched mains power that the C3D board will be POWERED ON 24/7/365 (if you have it directly to a wall outlet next to your K40 power plug, for example).

I assume that most people cut the mains connector off and wire it inside the power supply / controller board compartment directly to the output of the main machine power switch, correct?

(my new C3D board arrives tomorrow, so I’m just learning in advance)

Again, my answer to that will be no.

1 Like

Understood. However having an extra power strip on the outside of the machine just for this is a total non-starter for my design sensibilities. Since these power adapter cords are cheap and plentiful, I’ll proceed with direct wiring to the switch, but keep a spare cord as a back-up.

However, since main 110V power is only going through the one main switch on the top of the machine, then as long as it has reasonable metal-to-metal contacts, the brick should be fine for current and RF noise. My BS in Electrical Engineering is definitely rusty, but my Spidey senses aren’t tingling too much over this hook-up option.

I’ll report back if there are issues (and yes, I would try the untouched original cord directly to a wall outlet as my first debugging test).

Update: The new board is in place and running wonderfully. Thanks, Ray, for supporting a great little product. This board, plus LightBurn, is a great improvement in functionality for my K40. I love the way the motors are so quiet and smooth, too.

I have been running it from a power strip for now, to prove it out first, but soon I’ll wire the brick into the main K40 power switch for convenience, using a sacrificial ‘figure 8’ power cord off Amazon. If I have issues, then I’ll know it wasn’t a good choice, but I think it’ll be fine.