does ISR POE power module PWR-POE-4450 work alone?

[Herman2018]

Hi, can cisco ISR 4300 power POE Module (PWR-POE-4450) work alone when main AC power supply failed? please advise, thanks. 

[Leo Laohoo]

If the power fails, the router goes dark.

[Herman2018]

what I mean is the router with one normal AC power supply and one POE power supply PWR-POE-4450, when AC Power Supply fail, will POE power supply module (with AC power cable plugged in) provide the sufficient power to the router or the router will go dark?

Please advise, thanks.

[Georg Pauwen · Accepted solution]

Hello,

very good question. The PWR-POE-4450 is sold as 'redundant/hot-swappable'. 

'Redundant', in the power supply world, means that 'in the event that one of
the power supplies fails the extra power supply will be able to take over the full operation of
supplying power to the system or various subsystems and components as designed.'

As such, your router should work with just that one power supply.

[Herman2018]

thanks Georg for your kind advice!

[Herman2018]

Hi Georg, sorry, I have a further query about this question. Because POE power supply is designed for POE switch ports. So when main AC power supply fails, the POE power support has sufficient power to support system operation and support POE end devices operation as well? Please advise, thanks. 

[Georg Pauwen]

Hello,

indeed. The PWR-POE-4450 has 1000Watt, while the 'regular' power supply has only 450 Watt. That extra 550W ensures that both the switch and the PoE clients work. Obviously, if the POE supply fails, the regular power supply won't be able to support the PoE clients, just the switch operation.