Cisco 4000 Switch

Greetings guys,

Does Cisco 4000 series require a power supply? Looking at the cut sheets, it can tolerate input voltage level 10-60 V. I don't understand the benefit of adding a power supply. As long as voltage on the bus the Ethernet switch is connected to is robust, it seems the switch can be connected directly to the said bus.

Any thoughts?

Thank you,
EE

I used this documentation:
https://www.cisco.com/c/en/us/td/do...lation/guide4400-4300/C4400_isr/Overview.html


Looks like the switch comes with a PSU, with an optional redundant PSU. The other reason I've seen multiple PSU's on these is for increased POE capacity.


Voltage on the bus isn't "robust". You either have enough power to drive the load or you don't. Hence the optional power supply. Cut cost for those who don't need it, have the option if you ever do.