Avaya P460 - Manual (Page 35)

Chapter 4 Turning on the Avaya P460
Avaya P460 Installation and Maintenance Guide 21
Removing or Switching off a PSU
If there is one PSU
The entire chassis turns off
If there are two PSUs
1 When you remove a PSU from the chassis, the Supervisor Module recalculates
the power budget. If the power requirement exceeds the capacity of one PSU,
the I/O modules are then turned on according to the power budgeting scheme
described below. See Figure 4.1.
a
The chassis is automatically turned on with only the Supervisor Modules
and the fans getting power from the available PSU
b If all the available I/O modules were operational before the PSU removal/
failure, the Supervisor Module starts to apply power. The power is first
applied to as many I/O modules as possible within the power budget limit
of the single PSU. This can mean that an I/O module with a low power
requirement and low priority is powered up rather than a high power
requirement module with a higher priority.
c Slots whose power is disabled are skipped.
Figure 4.1 Power Allocation after PSU Removal
Start power allocation
Power enabled
for slot 3?
Sufficient power
budget?
Apply power to slot 3
Power enabled
for slot 4?
Sufficient power
budget?
Apply power to slot 4
Power enabled
for slot 5?
Sufficient power
budget?
Apply power to slot 5
Power enabled
for slot 6?
Sufficient power
budget?
Apply power to slot 6
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No