[ale] SemiOT, UPS for office telco/network

[Alex Carver]

On 2015-01-04 13:29, Ken Cochran wrote:
> Hello ALErs & Happy New Year :)
> I'm looking for a UPS for the telco/network closet/wall.
> Everything is 120v; if I'm doing my math right it looks like
> about 5 amps total, so 600VA (ish :).
> Equipment:
>   Nortel NorStar CICS
>   Ciena 3930 - some kinda fiber <-> ethernet thing
>   Arris TM604G & TM602G
>   Ubee DDW365
> 
> How do these work with or tolerate stepped-wave power or should
> I go for sine?  Doesn't look I have room for a rackmount unless
> I can mount one vertically.  Recommendations?  How about where
> to buy?  Refurbished is probably fine too.  Thanks y'all :)  -kc

All of those devices are using switchmode power supplies so they should
tolerate a modified-sine UPS with little difficulty.  True-sine UPS
systems are usually lower capacity for any given battery configuration
than modified-sine (the conversion is a little less efficient from DC to
true-sine compared to modified-sine).  Since they're all sensitive
equipment, they should (hopefully) all have their own internal line
noise filters to clean up the incoming power.  That helps for the
modified-sine systems which have harmonics.

Make sure you have more than adequate cooling when installing these.
Modified-sine power tends to make power supplies run a little hotter
(the filter and bypass circuits start to carry more current due to the
harmonic content).  Start with whatever the manufacturer recommends for
cooling needs and then add some extra cooling (add large external fans,
lower the room temperature, etc.)