http://elecraft.85.s1.nabble.com/Wattage-Draw-K3S-100-vs-KPA500-KAT500-for-UPS-tp7633842p7633917.html
That said, for my own use, I've got a 100Ah LFP from Blackwood Innovations
> There are also UPSes meant for extended runtimes that are a little less
> brutal on the batteries. One Upon a Time, I had a couple racks of APC
> SmartUPS 2000 units with daisychained batteries to give extended holdup to
> a couple of racks of telecom and server hw. No clue how RF noisy those
> units are, though.
>
> On Thu, Aug 31, 2017 at 10:46 AM, Lynn W. Taylor, WB6UUT <
>
[hidden email]> wrote:
>
>> I'm going to add that nearly every UPS made is meant to bridge the time
>> between when the power goes out, and the (automatic) generator starts.
>>
>> If you don't have a generator, the UPS signals the computer(s) so that
>> they can shut down gracefully and turn the UPS off.
>>
>> The (typically AGM lead-acid) batteries are sized for maybe 15 minutes,
>> which is way too fast. Drawing a lead-acid battery flat in 15 minutes will
>> kill it in only a few cycles.
>>
>> What I did as part of my ISP was to remove the batteries from my UPSes
>> and replace 7 or 12Ah batteries with 100Ah batteries outside the case.
>>
>> That didn't get me to the 10 hours for maximum battery life, but it got
>> me to 8 hours.....
>>
>> Jim's suggestion also lets you size the battery to run all the gear for
>> more than a few minutes.
>>
>> 73 -- Lynn
>>
>> On 8/30/2017 8:55 AM, Jim Brown wrote:
>>
>>> A FAR better way to provide UPS for radio gear is a 12V deep discharge
>>> lead acid battery or 14.4V LiFePO4 that is float charged by a suitable
>>> power supply. And as has been discussed several times, LiFePO4 batteries
>>> have the major advantage that their operating voltage stays above 13V for
>>> most of their discharge curve, while lead-acid batteries are below 12V for
>>> most of their discharge curve. This system is as quiet as the power supply
>>> used to float-charge the battery.
>>>
>>> With either battery type, care must be taken to not overcharge the
>>> battery.
>>>
>>> 73, Jim K9YC
>>>
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>
>
>
> --
> Scott Small
>
>
>
>