User's Manual

252 Power Management
5 Type a budget value of up to 7928 watts in the System Input Power Cap
text field.
NOTE: The power budget is limited to a maximum of three PSUs out of a total
of six PSUs. If you attempt to set a AC power budget value that exceeds the
power capacity of your chassis, the CMC will display a failure message.
NOTE: When value changes are specified in watts, the submitted value will
exactly reflect what is actually applied. However, when the changes are submitted
in either of the BTU/h or percent units, the submitted value may not exactly reflect
what is actually applied. This is because these units are converted to watts and
then applied; and the conversion will be susceptible to some rounding error.
6 Click Apply to save your changes.
Using RACADM
Open a serial/Telnet/SSH text console to the CMC, log in, and type:
racadm config -g cfgChassisPowerCap -o
cfgChassisInMaxPowerCapacity <value>
where <value> is the maximum amount of power (in watts) available to the
chassis.
NOTE: The power budget is limited to a maximum of three PSUs out of a total of six
PSUs. If you attempt to set a AC power budget value that exceeds the power
capacity of your chassis, the CMC will display a failure message.
For example:
racadm config -g cfgChassisPowerCap -o
cfgChassisInMaxPowerCapacity 7928
Throttling Power to Maintain Power Budget
The CMC throttles power to lower priority servers when additional power is
needed to maintain the maximum AC power limit. For example, when a new
server is engaged, the CMC may decrease power to low priority servers to
allow more power for the new server. If the amount of power is still
insufficient after throttling the lower priority servers, the CMC will throttle
higher priority servers until sufficient power is freed to power the new server.
Throttling is executed in two cases:
• Overall power consumption exceeds the configurable maximum power
limit (see "Setting the Power Budget" on page 251)