Cooling Requirements; Cabinet Design; Grounding - Delta HPH-20KA01KAT User Manual

Delta Electronics. Inc.

5.1. Cooling Requirements

For the HPH-20KA01KAT A supply to be sufficiently cooled, the cabinet must be set up to:.
1. Bring in coolant air of the correct temperature(40 ˚C maximum)
2. Distribute coolant air to the power supplies
3. Prevent air exhausted from the cabinet from circulating back and becoming input air
4. Exhaust the hot air from the cabinet with minimal airflow restriction.

5.2. Cabinet Design

The following is a synopsis of the HPH-20KA01KAT A to follow when designing a cabinet
containing a stack of HPH-20KA01KAT A power supplies.
Coolant air must be drawn easily into the cabinet; exhaust air must be able to pass
unrestricted out of the cabinet. If some physical constriant restricts the flow of exhaust air out of
the cabinet, we recommend that fans or blowers be mounted so that the hot air is removed from
the cabinet as quickly as possible.
Each HPH-20KA01KAT A power supply dissipates up to 10% of its maximum power at full
rated output. The minimum air flows in cubic feet per minute(CFM) required by individual HPH-
20KA01KAT A supplies are shown in table 5.1. The static pressure(inches of water) of the empty
cabinet should not exceed 0.1 inches of water at the CFM level obtained by adding together the
minimum CFM values for all the power supplies that will be placed in the cabinet. For example, if
three HPH-20KA01KAT A supplies are mounted in a cabinet, the minimum CFM requirement
would be three times the CFM of cabinet air volume compared to an individual supply.
Approximations of this figure, the total power dissipation, and the temperature difference between
coolant air and exhaust air are shown as an example in table 5.2.
Type of PSU
20KW
Table 5.2 Approximate cooling requirements for three units mounted in a cabinet
Type of PSU
20 KW x 3

5.3. Grounding

For your convenience, the rear panel of the HPH-20KA01KAT supply features three
equipotential ground screw: three M6 screw. These are indicated on the rear panel by a ground
symbol.See figure 6.2 for more information.
Table 5.1 Minimum CFM requirement for HPH-20KA01KAT unit
CFM for 3 Supplies
780 CFM
(260+260+260=780)
(368.1 liters/second)
CFM Required
260 CFM (122.7 liters/second)
Total Power Dissipation
9000 W
(3000+3000+3000=9000)
HPH- 20KA01KAT
Dif. In Temp. Between
Coolant & Exhaust Air
˚C
23
19