[c-nsp] Power Redundancy in 3550 or 3750?

[Andrew Fort]

Jan Friedel wrote:
>   Check the RPS675 solution.

<friday afternoon rant>
'Solution' is a strong word for the RPS675. :-)

Unfortunately, it's a bit of a joke.  You waste an additional 1RU per 
device you want redundant power for -- why?  Because the RPS is designed 
to protect against power supply unit failure, not power supply failure; 
i.e., if you plug in more than one device to the RPS, and lose mains 
power, only one of the devices attached to the (usually 5 or 6) power 
sockets will receive power.

So, although it's the only solution to Skeeve's problem, it's a space 
eater when you really just want another power supply that you attach to 
UPS as opposed to raw power.

Also, when you switch from RPS back to mains, the switch will power 
cycle; so power outages still require an outage, just that you get to 
choose when it'll be.  Rumor is that this is a design flaw.

</friday afternoon rant>

-andrew