[CentOS] [OT] ups advice

Fri Apr 15 15:11:20 UTC 2011
Howard Fleming <hfleming at moosebird.net>

On 4/15/2011 10:48, John R Pierce wrote:
> On 04/15/11 4:38 AM, Howard Fleming wrote:
>> I have used several Best Ferrups UPSs over the years, other than one
>> that toasted it's transformer, have never had any trouble out of them
>> (just replace the battery every 3 to 4 years....).
>> They are picky about their input power, do not run not connect them to
>> an auto regulating transformer (not the proper term?), or on the output
>> of other UPSs, it can cause interesting problems...
> I don't think they make any FerrUPS anymore.  Those were based on a
> massive ferroresonant transformer which, yes, is very sensitive to the
> input frequency.  Specifically, they don't like generator power, unless
> it has extremely well regulated frequency output (such as a DC generator
> with a digital sinusoidal converter)

Eaton has the Ferrups line now (still available as far as I know).

I have actually run into the input frequency problem in the past with 
the Ferrups.

I was working at a gas company that for political reasons generated 
their own power inhouse.  Had one Ferrups UPS (of 10?) that was 
complaining about it (kept going online/offline/online....  There is a 
parameter in the settings that can be adjusted to allow a greater input 
freq range on the UPS (59.5 - 60.5 hz is the default range, from what I 
remember).  In this case that took care of the problem.

I have 3 1.4kw units at home, no trouble to date running them off of my 
backup generator (Campbell 5k unit).  They are also 18 years old at this 
point and still going... :o).  Running 3 of my CentOS servers at home in