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 Which power supplies do Cisco Catalyst 4500 Series switches support with switch configuration?
Catalyst 4500 series switches support two types of power supply, which are as follows:
When deploying fixed power supplies, you must choose a power supply that can support the switch configuration. On the other hand, when using variable power supplies, you must choose a power supply that can deliver enough power so that the chassis and PoE (inline power) requirements are less than the maximum power available for the chassis and PoE.
When a system boots, variable power supplies adjust the power resources automatically.
Important Note: You must not use the 1400 W AC Cisco Power Supply with any other power supply, not even for hot swaps or other short-term emergencies. Otherwise, it will damage your switch and you may not be able to use your switch further.
When you use different types of power supplies for your switch, the switch uses the only power supply in power supply bay 1 called PS1, and ignores the other power supply. When using different power wattages, there will be no issue of power redundancy.
Catalyst 4500 series switches support two types of power management modes, namely:
The redundant mode uses only the primary power supply and keeps the secondary power supply as a backup. Thus, if the primary power supply fails, the secondary power supply fulfills the power requirements of your switch without disturbing your network.
The combined mode uses power from all power supplies installed to support your switch configuration. This mode has no power redundancy. Thus, if a power supply doesn’t function, it can lead to the shutdown of one or more modules.
The total available power in the combined mode is:
P + (P * ratio)
The choice of power supplies depends on your hardware switch configuration. For instance, if your switch configuration needs more power than a single power supply can provide, then you will need to use the combined mode. The only problem with the combined mode is that there is no power redundancy, which means if one power supply fails, another supply cannot fully support the power requirements, and one or more modules of your network might get disrupted.
Here is an overview of the available power for different power supplies:
Redundant Mode:
Here, chassis power includes power for the supervisor engine, inline cards, and the fan tray.
Combined Mode:
In this supply, the backplane consumes 10 W in both types of modes.
Redundant Mode:
Combined Mode:
In this, the backplane takes 10 W in the redundant mode.
Redundant Mode:
In the case of PoE (max), this power supply has 0.75 efficiency, and PoE has 0.96 efficiency. The DC input can vary for this power supply and is configurable.
Combined Mode:
N/A
Redundant Mode:
Combined Mode:
To calculate the power requirements and check that your system has enough power supply, you must add the power consumed by the supervisor engine(s), the installed modules, and the fan trays.
Are you looking for a Cisco switch power supply? Or, do you need help with deciding the right power supplies for your Cisco switches?