IBM XIV Gen3 Series, Руководство по планированию

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remedial measures to mitigate such environmental contamination before providing
repair or replacement of the XIV system. Implementation of such remedial
measures is a customer responsibility.
The following criteria must be met:
Gaseous contamination
Severity level G1 as per ANSI/ISA 71.04-1985
1
, which states that the
reactivity rate of copper coupons must be less than 300 Angstroms per
month (Å/month,
≈ 0.0039 µg/cm
2
-hour weight gain)
2
. In addition, the
reactivity rate of silver coupons must be less than 300 Å/month ( ≈
0.0035 µg/cm
2
-hour weight gain)
3
. The reactive monitoring of gaseous
corrosibleness must be conducted approximately 5 cm (2 in.) in front of
the rack on the air inlet side at one-quarter and three-quarter frame height
off the floor. For environments with special air handling equipment that
alters the normal distribution of airflow into the rack, reactive monitoring
of gaseous corrosibleness must be conducted at a location on the rack
where air is entering at the highest rate.
Particulate contamination
Data centers must meet the cleanliness level of ISO 14644-1 class 8. For
data centers without air-side economizers, the ISO 14644-1 class 8
cleanliness can be met by choosing one of the following filtration methods:
v The room air can be continuously filtered with MERV 8 filters.
v Air entering a data center can be filtered with MERV 11 or preferably
MERV 13 filters.
For data centers with air-side economizers, the choice of filters to achieve
ISO class 8 cleanliness depends on the specific conditions present at that
data center. The deliquescence relative humidity of the particulate
contamination must be more than 60% RH
4
. Data centers must be free of
zinc whiskers
5
.
Acoustic declaration
This information lists the acoustic (sound power) levels for the XIV system.
CAUTION:
Depending upon local conditions, the sound pressure might exceed 85 dB(A)
during service operations. Hearing protection must be worn when you are in a
room that has an XIV system while either the front or rear door is open or when
the front and rear doors are not installed.
The acoustic levels are shown in Table 29 on page 47. These measurements are
based on a typical XIV system configuration with 13 modules. All measurements
are in conformance with ISO 7779 and declared in conformance with ISO 9296.
1. ANSI/ISA-71.04.1985. Environmental conditions for process measurement and control systems: Airborne contaminants. Instrument Society
of America, Research Triangle Park, NC, 1985.
2. The derivation of the equivalence between the rate of copper corrosion product thickness growth in Å/month and the rate of
weight gain assumes that Cu
2
S and Cu
2
O grow in equal proportions.
3. The derivation of the equivalence between the rate of silver corrosion product thickness growth in Å/month and the rate of
weight gain assumes that Ag
2
S is the only corrosion product.
4. The deliquescence relative humidity of particulate contamination is the relative humidity at which the dust absorbs enough water
to become wet and promote corrosion, ion migration, or both.
5. Surface debris is randomly collected from 10 areas of the data center on a 1.5 cm (0.6 in.) diameter disk of sticky, electrically
conductive tape on a metal stub. If examination of the sticky tape in a scanning electron microscope reveals no zinc whiskers, the
data center is considered free of zinc whiskers.
46
IBM XIV Gen3 281x-11x, 281x-21x, and 281x-314 Planning Guide