Stratus ftServer 2600, Site Planning Manual

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Example of PDU Usage Calculation
5-4
Stratus ftServer 2600, 4500, and 6300 Systems: Site Planning Guide (R638)
Example of PDU Usage Calculation
Table 5-3 shows how to use the information from Table 5-1 to calculate the required
rack space and the current when the PDU is connected to a NEMA L6-20R receptacle
in the United States, with a voltage of 208V.
Table 5-4 and the explanation that follows show how to use the information from
Table 5-3 to determine when you need to buy an additional pair of PDUs or calculate
the size and number of cabinets you need.
Table 5-3. Example: Current and Rack-Space Requirements (208 volts)
Component Watts ÷
Site
Voltage
x 1.25 = Current (A)
Rack
Space
ftServer system 700 ÷ 208 x 1.25 = 4.21 4U
1U LCD monitor unit 54 ÷ 208 x 1.25 = 0.32 1U
Tape drive (typical) 80 ÷ 208 x 1.25 = 0.48 2U
ftScalable Storage
system
400 ÷ 208 x 1.25 = 2.40 2U
Table 5-4. Example: Calculating A-Side PDU and Rack-Space Requirements
1. Component
2. Cumulative
Space Used (U)
3. Cumulative
Number of
A-Side Outlets
4. Cumulative
Current (A)
PDU pair 2 0 0.00
ftServer system 6 1 4.21
1U LCD monitor unit 7 2 4.53
Tape drive (typical) 9 3 5.01
ftScalable Storage system 11 4 7.41
ftServer system 15 5 11.62
PDU pair 2 0 0
ftServer system 6 1 4.21
ftServer system 10 2 8.42