Page 8 - paruzzi-magazine-en-23

#67 Electrical voltage drops

Voltage divider

Because of all these extra resis- When electrical consumers are

tors, which in turn consume a connected in series, you may
small amount, the real consumer add their respective resistance

(the light bulb) will not get the values. The total resistance of the

full 12 V, part of the battery volt- circuit below is equal to the sum
age will be lost over the other of the three resistors:

(loss) resistors. This is the prin-

ciple of the voltage divider. Rtotal= R1 + R2 + R3

R1 R2 R3
+ 4V 4V 4V

U 12V

-

If the three resistors have an

equal value, e.g. three light bulbs

of 12 V/10 W, then the voltage

across each bulb (in ideal condi-
tions, i.e. all other parts of the

circuit have a resistor zero) will

12V be one third of the battery volt-

age, i.e. 4 volts.

8 Paruzzi Magazine 23