[c-nsp] ME3400 DC Power

[Justin Shore]

Doing this in a unit with 2 PSUs will give you PSU redundancy, should 
one fail.  It will also give you breaker/fuse redundancy, should one 
pop.  However it won't give you power source redundancy.  You still need 
a B feed connected to a PSU to get redundancy for the power source.

http://www.cisco.com/en/US/docs/switches/metro/me3400/hardware/installation/guide/HGDCPWR.html

In my experience you're more likely to lose a power source than a PSU. 
When it doubt wire the device as indicated with A & B to both PSUs. 
Though I would never wire a device this way, figure C-7 give you an 
option for daisy-chaining 2 power feeds through both PSUs.

Justin

Dan Armstrong wrote:
> The power supplies on the ME3400s have 2 inputs, for "breaker" 
> redundancy.. some models have to physical power supplies, some have only 
> one - in all cases, each supply has 2 inputs.  If your model has 2 power 
> supplies, you can hookup just the A side of each unit, and you'll be fine.
> 
> 
> 
> Dave Weis wrote:
>>
>> Do I need to supply both power supplies with an A&B side for 
>> redundancy or will I have redundancy if I have the A side of PS1 and 
>> PS2 connected?
>>
>> Thanks
>>
>> dave