[time-nuts] The home time-lab

David davidwhess at gmail.com
Fri Jul 8 11:56:50 EDT 2016

On Fri, 8 Jul 2016 11:23:39 -0400, you wrote:

>David wrote:
>> This is the only deal I see at the moment but I do
>> not know how suitable it would be and it is more
>> than I paid although about twice as powerful:
>> http://www.upsforless.com/apcsurta1500xlref.aspx
>I have a fleet of its bigger brothers, the 2000XL and 2200XL, and 
>recommend them highly.  The conversion engines are rated for continuous 
>duty, so you can add as many extra battery packs as you like to extend 
>the run time (most UPSs designed for home use -- even very expensive 
>ones -- do not have enough cooling to run continuously, so they depend 
>on the battery going dead to keep them from burning down).

Online or double conversion UPSes all have to be rated for continuous

I have an old Powerware 9120 which I bought new, two refurbished
Powerware Prestige EXTs, and two refurbished Leibert GTX2-700s.  The
Prestige EXTs are interesting because they can operate as line
conditioners without the batteries.  These all support external
batteries so I wonder if that is a ubiquitous feature with online

>That price is not bad, IMO, if they come with fresh, GOOD QUALITY 
>batteries. I strongly advise NOT using the generic black Chinese 
>batteries -- IME, they are worthless crap. If you live somewhere you can 
>get genuine Panasonic SLA batteries, use those [but BEWARE of fakes!!]. 
>Here in the US, the PowerSonic SLAs are the best I've found.  I get mine 
>from "ecomelectronics" on ebay [no affiliation, just a satisfied customer].

I am actually on the hunt for replacement batteries now so thanks for
the tip; I will check them out.

>I have had no RF interference issues, or any other problems other than 
>bad, generic black Chinese batteries.  The APC supplies are rugged and 
>well-protected -- one battery pack I hadn't rebuilt (full of the generic 
>black batteries) failed in a spectacular fashion (sparks and smoke and 
>melted plastic *from the batteries*).  The UPS itself suffered no damage.

The local HAM club has been looking for sine wave UPSes and inverters
which produce minimal RFI without much luck.

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