Symbol Recommendations For Power Policy - Symbol ES3000 Manual

Changes made to this screen will not take effect until the administrator clicks the Apply button. The
PoE Global Configuration page displays the following parameters:
• Power Budget: Maximum total power available for all PoE ports. The switch has a power
budget of 170 watts. This value cannot be changed.
• Detection Method: Enables or disables the capacitance detection method to determine
whether a powered device requires power. This parameter applies only to older powered
devices. If capacitance detection is enabled, the switch applies capacitance detection to
determine whether the device requires power. Older devices might not be recognized by the
switch when capacitance detection is disabled. The switch detects newer powered devices
regardless of the setting of this parameter. The default is Capacitor Detection Disabled.
• Power Management Method: Sets the method the switch uses to determine which ports
receive power when the power budget is exceeded. Two methods are available:
• Deny next port connection, regardless of priority: The switch continues providing power
to previously connected and enabled powered devices, and denies the request of a
newly connected or enabled powered device. This is the default setting.
• Low-priority port will be shut down: The switch searches previously connected powered
devices for one with a lower priority than the new powered device. The switch
discontinues power to the lower-priority device and gives preference to the higher-
priority device. If the power budget is still exceeded after discontinuing power to the
lower-priority device, the algorithm loops to find the next lowest-priority port to shut
down.
• Power Usage Threshold: The threshold at which to enable a SNMP trap to warn an SNMP
trap receiver that power usage is above a threshold level. This is a warning only, and does
not affect power supplied to the ports. The administrator can set this value as a percentage
of the total power budget. When the total power provided by the switch to all ports exceeds
this percentage of the power budget, an SNMP trap is sent. The trap is only sent if an SNMP
trap receiver has been set up. The default value is 80%.

4.2.4 Symbol Recommendations for Power Policy

Symbol believes that most installations will be optimally served by the following power policy:
• Set the power limit for the powered devices to the limits recommended in
Port PoE Limits on page
• Do not let the total of all power limits exceed the 170 watt power budget.
• Set power priority of ports with PoE devices on them to critical or high.
4-4.
4-5
PoE Power Management
Symbol Access