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MODULE POWER REQUIREMENTS
SIZING THE MODULAR POWER SYSTEM
B - 6
I-E96-508C
Q1 = number of PDS power modules needed to meet 5 and
24 VDC current 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
QS = the largest value of Q1, Q2 or Q3
QS(N) = number of PDS power modules needed to power the
system
QS(N+1) = number of modules needed for N+1 redundancy,
add 1 to the value of QS(N)
The following equations should be used when sizing systems
having only PDS supplies.
If B
≥
A/5 then Q1 = (A/20) + (B/4)
If B < A/5 then Q1 = A/10
Q2 = C/0.5
Q3 = D/0.5
QS = largest value of Q1, Q2 and Q3
QS(N) = value of QS rounded to the next highest integer =
number of PDS power modules required
QS(N+1) = if using N+1 redundancy, add 1 to the value of
QS(N)
NOTE: The tables in
contain calculated values of Q1, Q2
and Q3 for various load combinations. These tables enable you to
size the modular power system without doing the sizing calculations.
Figure B-1. Power Output of One IEPDS01/02 Module
OUTPUT CURRENT OF
25.5 VDC OUTPUT (AMPS)
OUTPUT
CURRENT OF
5.1 VDC
OUTPUT
(AMPS)
102 W
OUTPUT MAX.
MAX. POWER
OUTPUT OF PDS
TP25244A
1
0
2.5
5.0
7.5
10.0
2
3
4