On Tuesday 20 November 2018 14:29:53 Chris Albertson wrote: > I think the only reason to have a UPS on a machine is if you actually > wanted to run the machine after losing AC power. that case the UPS > would be sized to power the entire machine, motors and all. > Exactly. And in my case it won't need a whole lot of holdup time because theres a 20kw nat gas fed generator that is up and delivering power to the whole property by 15 seconds after the lights blink off. Worst case I'd need 10kw for say 20 seconds. That generator was about $8.5k installed, cheaper than a ups that honking big. But to have a power hit while one of my machines was doing something (they aren't on the ups driving parts of this room) has yet to wreck a part, or a filesystem. But thats only happend a time or maybe two in the last 15 years.
> If you are concerned about file system corruption on power failure, > two things can help (1) use a modern Journaled file system. These are > VERY crash resistant. Most Linux distributions do use Journaled file > system like ext4. ext4 is very robust. and if you are very worried > use a write-only file system to hold all the non-volatile files. > This method is near "bomb proof" but takes some effort to set up. > > On Tue, Nov 20, 2018 at 7:10 AM Thaddeus Waldner <thadw...@gmail.com> wrote: > > My question is, *should* a controller such as this have an > > uninterruptible power supply? If so, what parts of the machine are > > normally served by a UPS? The only thing I'd worry about on this surface grinder is the z drive if its a servo which on loss of power may run free, dropping the wheel into the work. But immobilizing that would be far easier done by dropping a lock onto it on loss of power. If the lock hooked into a drive belt, it might be possible to pull the belt a tooth or so higher if its rigged right, lifting the wheel a few microns for the ultimate in safety for the workpiece. If a stepper, it usually has enough power off cogging to hold it where it was. I've never had the head on the G0704 try to fall unless the motor is removed. My $0,02. -- Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
