[ale] OT: slow back-UPS

[Dow Hurst]

Cor van Dijk wrote:

>Greetings,
>I have several power backup units and they work ok with pc's. I also
>have a digital audio recorder,
>for which they do not work. It appears that the response time is too
>slow. All of the ones I have
>checked have a response time of 150 ms (or better they say), which is
>almost 9 cycles.
>Is anybody aware of faster ones or a way around this problem? The
>recorder takes only 30 Watts,
>so that should not be a problem. TIA.
>Cor van Dijk.
>
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>  
>
Cor,
I would go to Tripplite, Powerware, and APC and look at the online 
UPSes.  Then go to Liebert and look at the specs on theirs.  The main 
difference between online UPSes is the noise allowed in the power as the 
whole point is to have zero transition time.  A laboratory based NMR 
would need an expensive Liebert to keep the noise down.  A simple PC 
doesn't usually need an online UPS.  Your digital audio recorder may not 
have a power supply that provides enough current/voltage to last 9 
cycles.  Also, circuits protected by a generator may have so much noise 
and variation in frequency and voltage that a UPS may shut off if not 
built to handle it.  Mainly, a critical application with low power 
requirements like yours might do well with the lowest power online 
doubleconversion or ferroresonant UPS.  Best and Exide combined to 
become Powerware so you can get the ferroresonant UPSes there.  You pay 
more for the true online UPSes.  Research on UPSes can become a black 
hole but is fun going into.  There are so many options out there!  A 
700VA Ferrups UPS would work as well as a option.  Maybe if you called 
APC and talked with a salesman that they could tell you if you could 
plug a line conditioner inbetween your DAT and the UPS you currently 
have.  Their Line-R conditioners are $40-60 so wouldn't be too expensive.
Dow