Why is my new meanwell lrs-350-24 fan ramping up and down?

[GreenFlagMan]

I'm building a bigger CNC router now and upgraded from a tiny one to a decent sized 2x4 foot machine, which is the Mean Well LRS-350-24. I got two of these Mean Well power supplies, one for the machine and one for the spindle. The spindle one has been fine, but the router one is acting all wonky.
I turn the router on, it runs fine for about five minutes. Then, the power supply just... blinks out, then comes back on, but only at half power (12 volts instead of 24). The meanwell lrs-350-24 fan ramping up and down. I swapped in the power supply that was working fine with the spindle, and it did the same thing!

This is what I have:
Hobbycnc EZ board
2ea Nema 23-305 & 1ea Nema 23-425 stepper motors operating
belts on the X and Y and a lead screw on my Z
LinuxCNC to control software
shielded wire for the motors

I spent an hour setting up LinuxCNC, and it was fine then, but now it's acting up even when the machine's just sitting still. My brand new meanwell lrs-350-24 fan ramping up and down and going nuts! I'm about to throw them out and go back to my old setup. Anyone got any idea why this is happening?

 

[jonbonjourvie]

Hmm, I see what's going on here. Is this overheating? Which climate do you live in and or what's your room temperature? When it overheats it does that. Have you tried running the device without cover? This makes sure there's air in the system you know it's really easy to troubleshoot if it's just that. If your stepper monitors are pulling too much power then this is also solvable by just removing motors. But I'm worried if this is a wiring issue! Gotta seek help from repairs if that is in fact the problem.

 

[GreenFlagMan]

Hmm, I see what's going on here. Is this overheating? Which climate do you live in and or what's your room temperature? When it overheats it does that. Have you tried running the device without cover? This makes sure there's air in the system you know it's really easy to troubleshoot if it's just that. If your stepper monitors are pulling too much power then this is also solvable by just removing motors. But I'm worried if this is a wiring issue! Gotta seek help from repairs if that is in fact the problem.

is there any manuals for this? I'm too annoyed to bring it to the mechanic and want to try to repair it myself

 

[IVGrbn]

The repeated failure with both power supplies strongly suggests an external issue, not faulty units. That half-voltage and fan cycling points to the Mean Well going into protection from an overload or short. Since it happens at idle, scrutinize all your wiring, especially to the stepper drivers and motors. Even shielded wire can have internal shorts. A single shorted motor coil could trip the power supply. Also, confirm your NEMA 23 motors aren't exceeding the HobbyCNC EZ board or Mean Well's current limits. You can usually find Mean Well manuals on their official website or by searching the model number online. I guess you can postpone going for professional repair after all those thorough inspection and ruling out all other possibilities!

 

[Kwanda_Rosman]

Hold up, this isn't just a fan glitch. The power supply is probably entering a hiccup mode because your load (motors/driver board) is drawing too much or causing startup inrush weirdness. That half-voltage spike is classic overload behavior, even if everything seems quiet. Measure your current draw and maybe add a soft-start if needed.

 

[cuts&circuits]

Increased fan speed and voltage dips may indicate a potential thermal overload or unstable current situation. It's a good idea to check the airflow around the LRS-350-24 and make sure it's not surpassing the rated amperage, particularly during motor start-up or idle phases. Also, keep an eye out for any grounding or electromagnetic interference issues that could stem from stepper wiring. To test for stability, consider isolating the power supply from the motors and control board. If both units show similar behavior, the issue is likely related to either environmental factors or the load itself. You can find the manuals for the LRS-350 series on ManualsLib.