D Calculating Noise Levels - HP Cluster Platform Introduction v2010 Introduction Manual

D Calculating Noise Levels

Use the following formulas to calculate noise levels:
• Formula 1: The declared A-weighted sound power level according to ISO 9296 and ISO 7779
L :
WAd
L = log[N
WAdT
Where:
— L
WAdT
— L
WAd1
— N
1
— L
WAd2
switch.
— N
2
• Formula 2: The declared A-weighted sound power level according to ISO 9296 and ISO 7779
L :
pAm
L 10*log[N
pAmT
Where:
— L
pAmT
— L
pAm1
— N
1
— L
pAm2
switch.
— N
2
For example, a 17-node CBB (with 17 HP Integrity rx2600 servers and one HP ProCurve
model 2650 network switch) has the following noise values according to ISO 9296:
Mode
Idle
Operating
See the specifications documentation for an individual component (such as a server) to obtain
declared noise levels of individual components.
*10^(L ) + N
1 WAd1
is the declared A-weighted sound power level for entire rack.
is the declared A-weighted sound power level for the first type of server or switch.
is the number of the first type of server or switch.
is the declared A-weighted sound power level for the second type server or
is the number of the second type of server or switch.
*10^(L /10) + N
1 pAm1
is the declared A-weighted sound power level for the entire rack.
is the declared A-weighted sound power level for the first type of server or switch.
is the number of the first type of server or switch.
is the declared A-weighted sound power level for the second type of server or
is the number of the second type of server or switch.
*10^(L ) + .....] in bels.
2 WAd2
*10^(L ) + .....] in decibels.
2 pAm2
L
WAdT
7.5 B
7.6 B
L
pAm
59 dBA
60 dBA
56