IBM XIV Gen3 Series, Руководство по планированию

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Materials for the secondary cooling loops
You can use any of the following materials in supply lines, connectors, manifolds,
pumps, hoses, and any other hardware that makes up the closed-loop
water-supply system at your location:
v Copper
v Brass with less than 30% zinc content
v Stainless steel – 303, 304, or 316
v Ethylene Propylene Diene Monomer (EPDM) rubber, peroxide cured, non-metal
oxide
Materials to avoid in secondary loops
Do not use any of the following materials in any part of your water supply system.
v
Oxidizing biocides (such as, chlorine, bromine, and chlorine dioxide)
v
Aluminum
v Brass with greater than 30% zinc
v Irons (non-stainless steel)
Water supply requirements for secondary cooling loops
Ensure that the following requirements are met for the system that supplies the
chilled conditioned water to the heat exchanger.
Temperature
The heat exchanger, supply hose, and return hoses are not insulated and
do not have features that are designed to address the creation and
collection water from condensate. Avoid any condition that might cause
condensation. The temperature of the water inside the supply hose, return
hose, and the heat exchanger must be kept above the dew point of the
location where the heat exchanger is being used.
Attention: Typical primary chilled water is too cold for use in this
application because building chilled water can be as cold as 4 - 6°C (39 -
43°F).
Important: If the system that supplies the cooling water is not able to
measure the room dew point and automatically adjust the water
temperature, the minimum water temperature that must be maintained is
18°C ±1°C (64.4°F ±1.8°F). The minimum water temperature is consistent
with the ASHRAE Class 1 Environmental Specification that requires a
maximum dew point of 17°C (62.6°F). See the ASHRAE document Thermal
Guidelines for Data Processing Environments. You can find information
about obtaining this document on the ASHRAE website
(www.ashrae.org/home/search?k=Thermal%20Guidelines%20for%20Data
%20Processing%20Environments).
Pressure
The water pressure in the secondary loop must be less than 689.66 kPa (100
psi). Normal operating pressure at the heat exchanger must be 137.93 kPa
(20 psi) or less.
Flow rate
The flow rate of the water in the system must be in the range of 23 - 38
liters (6 - 10 gallons) per minute.
Chapter 10. Planning for the rear-door heat exchanger
75