Users Guide

Switch Feature Overview 85
Power is supplied to the device in class mode per the following table:
In four-pair mode, twice the power listed in the table above is delivered. For
information about the available system power, see the Hardware Overview
chapter.
Power Management in Guard Band
The Dell EMC Networking N1100P-ON, N1500P, N2000P, N2100-ON,
N3000P, and N3100-ON Series switches support a dynamic guard band, which
means that the guard band used varies depending upon the following factors:
• Power management mode
• Class of the device being powered up.
Prior to a device being powered up, the switch calculates the following:
threshold power – guard band – (current power consumption + computed
power draw of the new device)
If this value is less than zero (which means powering up the new PD device
will put the total power draw into the guard band or above the switch power
capacity), then the switch does not power up the new device. A device being
powered up in class or dynamic mode is always supplied with the maximum
power (32 or 64 watts) at startup. Once the device class or power draw is
determined, power to the device may be reduced.
The power management mode is configured using the power inline
management command. The guard band is calculated by the switch as shown
below. The user- defined threshold power limit can be found with the show
power inline detailed command, and is configured with the power inline
usage-threshold command. Threshold Power is reduced by the guard band
when powering up a port.
Class Usage AF Device (Watts) AT Device (Watts)
0 Default 16.4 33
1 Optional 5 33
2 Optional 8 33
3 Optional 16.4 33
4 Optional 16.4 33