back up power/conditioner questions


Limp Gawd
Aug 18, 2005
1. My wife wants a computer in her hobby room which has a couple small sewing machines. If i put a PC on the same circuit as these sewing machines, will i have a problem as far as motors messing with the electricity? I am not concerned about tripping the breaker, my main concern is hurting the computer some kind of way.

2. With the above question in mind, will a APC backup resolve any issues?

3. How do i size a backup battery device as far as wattage is concerned?

Thanks for any advice or suggestions


[H]F Junkie
Nov 19, 2008
With the above question in mind, will a APC backup resolve any issues?

Not a consumer oriented model. I mean you probably need an online (or always on) UPS instead of a UPS that only uses the batteries when the voltage is low or high.

How do i size a backup battery device as far as wattage is concerned?

I usually get a 1000VA or 1500VA model for a single PC because I want a minimum of 30 minutes of run time. You are probably not looking for that however.

Also you probably want a line conditioner instead of a UPS.


[H]F Junkie
Mar 18, 2010
1. I doubt the motors will have any kind of effect on the computer. You're overthinking things, and good power supplies are made to handle tolerate imperfect currents, and correct them before passing it on to the computer components.

2. The only use for a UPS is if the power goes out, or the power line goes out of spec somehow (like a surge).

3. The larger the VA, the longer it will run. Doesn't really matter what the wattage is as long as it meets the requirements of the computer and whatever else you plug into it.

I doubt you need a line conditioner, unless you have frequent power problems. Which I doubt you do, since I'm assuming you have other computers which don't require a line conditioner.


Apr 3, 2008
It wont be an issue.
The motors in sewing machines don't put enough surge on the line to effect a pc supply.
One of my clients has 3 industrial sewing machines and a computer on one line with no issue for years.


Limp Gawd
Sep 28, 2009
I have a PC that is always connected to an APC 750VA UPS. I have frequent power loss (I live in Puerto Rico, with many storms and a very bad power gird), and many power surges that are a quick loss or spike of power that will not even turn my tv off, but would kill my PC. I have found with my PC that runs on average 250 watts (that includes a monitor, cable modem, router, and the pc), and at most 500w when gaming that I get about 3-8 minutes for backup, which is plenty before the diesel generator kicks in.

My point is if you are worried about data loss, or any damage, you can get away with a relatively low VAC UPS, just enough to keep your PC running while the AC line regulates after a significant amount of power is pulled from the same circuit. I picked up my UPS for $60.00 on sale and it has been more then worth it's weight in gold with as many times I have seen it save my data, and HD's.