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Lantronix
SM24TBT2DPA and SM24TBT2DPB Web User Guide
if all Critical ports are receiving power. Assign the most critical powered devices to Critical level. If
there is not enough power to support all the ports set to Critical priority level, power is provided to the
ports based on port number, in ascending order. See “
Port priority impact
” below.
Capacitor Detection
: The PoE capacitor detection for the port; check the box to enable Capacitor
Detection to support legacy PD's that were designed before the IEEE standard was finalized. The default
is disabled.
Maximum Power
: Set the maximum power in watts that can be delivered to a remote device.
The maximum allowed value is 90 W. In Class mode and LLDP-MED mode, the Maximum Power fields
have no effect.
PoE Power Note
:
Power Supplies
Available PoE Power
With 2 Power Supplies
Max 90 Watts output per port. Max PoE Budget 1640 Watts.
60 Watts for (24) ports simultaneously
90 Watts for (18) ports simultaneously
With 1 Power Supply
Max PoE budget 820 Watts.
30 Watts for (24) ports simultaneously
60 Watts for (13) ports simultaneously
90 Watts for (9) ports simultaneously (see Note below)
Note
: There are several ways to supply 90 Watts to the PD, mainly depending on the way the PD is
requesting power. Different PDs may need to be configured different ways. Moving forward when both the
PSE and PD support full 802.3bt standard will be easier. Below is one way to configure the switch to
provide 90W with one power supply:
1. Make sure the switch is at FW v 6.54.3178 or above and PoE FW v 208-211 (2.11) or above.
2. Set Reserved Power Determined by to Allocation.
3. Set Power Management Mode to Actual Consumption.
4. Set PoE Mode to Enabled for the switch to support PoH mode to supply 90 Watts to the PD.
5. Change the Maximum Power first (to 90W) before you click Apply.
6. Change Reserved Power Determined by to LLDP-Med then click Apply (in Class mode and LLDP-
MED mode, the Maximum Power fields have no effect). If you change the Maximum Power with
Allocation selected and click Apply before moving to LLDP-Med, the message
The value of 'Max.
Power' is restricted to 0 - 60 watts.
displays. See the Example below.
Buttons
:
Apply
– Click to save changes.
Reset -
Click to undo any changes made locally and revert to previously saved values.
Port priority impact
:
Power-up order
: After a reset, the ports are powered up based on their priority, highest to lowest, with
highest (Critical) priority powering up first.
Shutdown order
: When exceeding the power budget, lowest priority ports will turn off first.
Messages
:
The value of 'Max. Power' is restricted to 0 - 60 watts.