Here is a note from Aditi in reply which came in an e-mail because of a problem, replying to this thread due to the way the forum software appears to deal with percent signs! Even though they appear correctly in the quoted text, unless you enter them as their HTML code of & # 3 7 ; (without the spaces), it will reject your post. This applies to text you have quoted too.
The reason for putting the additional 10% for reliability is because the track feed voltage may vary a bit as the voltage on the signalling power distribution changes under conditions of different loadings and fluctuations of incoming supply.
If you remove the additional 10% to calculate Rs, then you get the following:-
id = 0.04*0.65 = 0.026A
Vrail1 = 0.026 * (9 + 8.5) = 0.455V
if1 = (5
The reason for putting the additional 10% for reliability is because the track feed voltage may vary a bit as the voltage on the signalling power distribution changes under conditions of different loadings and fluctuations of incoming supply.
If you remove the additional 10% to calculate Rs, then you get the following:-
id = 0.04*0.65 = 0.026A
Vrail1 = 0.026 * (9 + 8.5) = 0.455V
if1 = (5