Preliminary Information
If R23(max) < R23(min), then a violation has
occurred. Pd(max) will have to be increased.
A numerical example:
Given:
R2 = 220Ω
Lr = 325Ω (2.5km of 28 gauge wire, averaged at
65Ω/km)
DCRP = 200Ω
Pd(max) = 1.5W
Vbat = -48V +/- 10% (i.e. -43V to -53V)
Therefore:
R23(max) = (43/30mA) - 100 - (2 * 220 + 325 + 200)
= 1433.3 - 100 - 965
R23(max) = 368.3Ω
R23(min) = (53/40mA) - (1.5/1.6mA) - 220
= 1325 - 937.5 - 220
R23(min) = 167.5
Ω
R23 = Square Root ( 368.3 * 167.5 )
R23 = 248.4Ω
MT91600
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