Random shutoffs

I am posting here rather than problems or support since I had already emailed them and didn’t want to double their tickets, but wanted folks to know. So recently several times I have noted that my GF listed as offline, and when I went down to the GF is was powered down (with the switch in the on position). After turning it off via the switch it will only turn back on if I wait 10 seconds or so. It is on a beefy 1500va UPS so has clean power.


There have been several reports of units spontaneously rebooting. I wonder if this may be related.

1 Like

A couple of questions about the UPS:

  • is it a pure sine wave output? I’m assuming “yes”.
  • is it an always online design?

Most UPSes are not the always online style. Instead their normal state is “pass the mains power straight through to the output while keeping the battery charged.” When they notice a sufficient drop in the mains, they switch to disconnect the mains and begin pulling power from the batteries to feed the inverter to power the output.

Unfortunately, most UPSes are less about providing clean power and more about emergency backup.

The Glowforge seems very susceptible to quick power drops. I’ve had two power flickers interrupt prints that did not cause the TV in the next room to turn off. It is possible that the Glowforge might be susceptible to the switching time of the UPS.

A good way to test this would be to simulate a power blip by unplugging the UPS from the wall while the Glowforge is on.


It’s an APC and they comment they filter, reshape and brownout protect. We use them in our data centers too.


If it is a good UPS it is probably not part of the problem, but I would still run without it for a while and see if you notice any changes.

Yep, that sounds like an active one. If it were me, I’d still test it :blush:

1 Like

Obviously the GF is hinting that you should take a break.

1 Like

have seen the same on my replacement unit

I don’t know about this situation, but my undersatnding is that the UPS units we use are $2k and cost that much for good reason… they definitely handle dirty power situations. The power flickered at CES, for example, and half the booths went down rebooting; the Glowforge units on display finished their prints. (Other halls had a total blackout - we just had blinks).


I saw that power blip on the Lulzbot video that their whole cell shutdown midpoint. The Prusa I have on the same circuit has not had any problems (and yes, I have calculated the load, plus the APCs alarm when the current is high)

That behavior sounds like a PTC resettable fuse tripping. Hmm.

1 Like