3com S7906E Instruccion De Instalación

 

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Where the maximum PoE power may be lower than the sum of the maximum power required by all 

PSEs, PSE power management is applied to decide whether to allow PSE to enable PoE, whether to 

supply power to a specific PSE and the power allocation method. Where the maximum PoE power of 

the device is higher than the sum of the maximum power required by all PSEs, it is unnecessary to 

enable PSE power management. 

When PoE supplies power to PSEs, 

z 

If PSE power management is not enabled, no power will be supplied to a new PSE when the PoE 

power is overloaded. 

z 

If PSE power management priority policy is enabled, the PSE with a lower priority is first 

disconnected to guarantee the power supply to the new PSE with a higher priority when the PoE 

power is overloaded. 

The power supply priority levels of PSE include critical, high and low in descending order. 

If the guaranteed remaining PoE power (maximum PoE power minus power allocated to the critical 

PSE, regardless of whether PoE is enabled for the PSE) is lower than the maximum power of the PSE, 

you will fail to set the power priority of the PSE to critical. Otherwise, you can succeed in setting the 

power priority to critical, and this PSE will preempt the power of the PSE with a lower priority level. In 

the latter case, the PSE whose power is preempted will be disconnected, but its configuration will 

remain unchanged. After you change the priority of the PSE from critical to a lower level, other PSEs 

will have an opportunity of being powered. 

 

 

The guaranteed PoE power is used to guarantee that the key PSEs in the device can be supplied with 

power all the time, without being influenced by the change of PSEs.   

 

Follow these steps to configure PSE power management: 

Enter system view 

— 

Configure a PSE power 
management priority policy 

Required 

Not configured by default. 

Configure the power supply 
priority for the PSE 

poe priority { critical | high | 
low } pse pse-id 

Optional 

low by default. 

 

The power supply priority of a PD depends on the priority of the PoE interface. The priority levels of 

PoE interfaces include critical, high and low in descending order. Power supply to a PD is subject to 

PoE interface power management policies.