Laser lost cutting power. Tube amperage down 75 percent

I have an omtech 100 watt almost 2 years old.

Has a reci w4 installed since April. Original power supply

Was fill engraving and had a sudden loss of laser power,

Went to try and do a test cut which I normally do at 25mm/s and 77 power witch puts me at 24 mA on the power supply display. Won’t through cut it’s only engraving 1/4” plywood. Meter only showing. 6 mA.

It struggled to mark painters tape anywhere including directly in-front of the tube at a 20 percent pulse.

I’ve loaded machine settings from a backup file with no change.

How do I diag this ?

Assuming there’s no sudden smell of electrical death indicating a leaky high-voltage wire, it’s down to the tube, the power supply, or the PWM output of the controller.

On the Ruida’s control panel, set up a manual pulse at 50% PWM. Measure the voltage between the power supply’s L and GND terminals, which should be about 2.5 V during the pulse. If it’s not, then something is wrong with the controller, but that seems highly unlikely.

Power supplies being (relatively) cheap and easily available, I’d swap in a new one. If the tube now runs at full current, you’re back in business: toss the old power supply.

Otherwise, you just bought yourself a nice backup supply and are in need of a new tube. If the Reci is still under warranty, I think you have all the evidence required for a claim.

Thank you. That’s what I needed to know to atleast test the controller. Didn’t know what signal or where.

I’m a master tech at a new car dealer. And just have no information or knowledge about how everything communicates.

I already have a new controller coming from cloudray but it’s going to be atleast a week. And this is my busiest time of year. May have just sealed the deal on a second identical machine and a smaller k40 for redundancy. Have $1k in orders from this morning that I’m having to contact customers on.


For the revenue hit you’re talking, fire off a preemptive order for a Cloudray power supply from Amazon, also with delivery in about a week:

They apparently sell on Amazon but do not honor warranty claims even when buying from their “Cloudray Store”, so perhaps getting the same thing for slightly less directly from them may be better:

Good hunting …

I bought they 120 watt directly from their website. Estimated a rival was faster and cost less then Amazon.

Just to be clear is the 5v own to the power supply ac or dc.

The 5V terminal on the power supply is a DC logic supply output, although they don’t have any information on how much current it can provide.

Basically, you just unplug the green terminals from your old supply, disconnect the HV anode wire and the cathode return wire, swap the supplies, then plug everything in again.

I took the opportunity to improve the cathode wire connections, but that’s just me being me.

I was asking about the pwm from the controller to the power supply.

The pwm is a ttl signal level LPWM1 → IN of the lps. None of these signals on this type of machine is ac except the mains voltage…

Before you go changing things around test your tube for resonance…

It should be in TEM0 mode…

Good luck


Thank you I did not know it was all dc. Home with the flu and don’t have my fancy probes and meter here to help measure it just trying to rule out an error while k hold everything in place and try and push the buttons.

Abs it’s in tem01. Has been since the day I got it. It will barely mark tape but it it’s still a circle.

Should have asked for a new tube… TEM1 state is not where it should be and it will get worse from there…

Good luck