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MODULE POWER REQUIREMENTS
SIZING THE MODULAR POWER SYSTEM
B - 8
I-E96-508C
Q1 = number of PDS power modules needed to meet 5 VDC
requirements
Q2 = number of PDS power modules needed to meet
+15 VDC current requirements
Q3 = number of PDS power modules needed to meet
-15 VDC current requirements
Q4 = number of PDF power modules needed to meet
24 VDC current requirements
QS = the largest value of Q1, Q2 and Q3
QS(N) = number of PDS power modules needed to power the
system
QF = calculated number of PDF power modules needed to
meet associated I/O current requirements
QF(N) = number of PDF power modules needed to meet
associated I/O current requirements
QS(N+1) = number of modules needed for N+1 redudancy,
add 1 to the value of QS(N)
The following equations should be used when sizing systems
having both PDS and PDF supplies.
Q1 =
If (Q1 - A/10) < 0 then use Q1 = A/10
Q2 = C/0.5
Q3 = D/0.5
QS = largest of Q1, Q2 and Q3
QS(N) = value of QS rounded to the next highest integer =
number of PDS modules required
If Q1 = 0 then use QF = B/4
QF = B
×
[5/(20 - A/QS(N))] - QS(N)
If Q1 = 0 then use QF = B/4
QF(N) = value of QF rounded to the nest highest integer =
number of PDF modules required
A
B
×
80
A
2
1600
⁄
+
⁄
A 40
⁄
+