Curious
I live in Canada up North on and Island and on and off in the winter we can get a power outage.
Being a computer tech for 15 years I use a UPS BATTERY BACK UP on my
my computers and for those that do not know what it is.
It is a power box that supplies enough power to my computer for at least 15 minutes,
so I get a chance to save my work.
Being new to this forum and CNC I'm curious of this situation.
I now have my computer and Milling machine plugged in a power bar that  feeds
from my UPS BACKUP if the power goes out.
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Who has experienced a power outage will milling, and has this caused you to
start all over again, because you may have lost a few steps as the power went out.
Or when the power comes back on the work continues without a screw up
Thank you,

A *good* UPS like an APC has zero switch over time, since you're running off the inverter 100% of the time.

Assuming it has enough poop to run all of the equipment, and batteries big enough to see things through to the end of the job.... It shouldn't make any difference!

Personally, I run several large (1500&3000va) units, with stand alone battery packs.  I can see 6-10hours run time!  Depending on load of course.

IT would be much better to learn to reset your work coords and restart.

Just a thought, (;-) TP

Glad to see I'm not alone in the thinking of back up.
By resetting the coords do you mean back to a point where it was all good before the power went out.
Like starting a few steps back before the power went out.
Or can you do a short reverse run back a few steps.??
Just thinking

EVery large job I do I create a reference point on the machine or fixture. Normally a bored hole in the fixture. IF power goes down all I have to do is re reference that hole and apply the positional values to XY and restart from where ever you want. No harm or foul.

The same can be done with accurate home switches. Rerefence the machine and restart where you want.

Just a thought, (;-) TP

Thank you