Nace CP 1, Course Manual

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Basic Electricity 1:12
CP 1 – Cathodic Protection Tester Course Manual
©
NACE International, 2000
02/01/05
For example, consider the following circuit, where:
E
T
= Total Voltage Across the Circuit
R
T
= Total Resistance in the Circuit
I
T
= Total Current in the Circuit
E
1
E
2
R
1
R
2
R
3
I
E
2
E
1
R
3
R
2
R
1
Figure 1.6 Series Circuit
Given
E
1
= 5 V
E
2
= 5 V
R
1
= 5 Ω
R
2
= 3 Ω
R
3
= 2 Ω
Ω = Ω + Ω + Ω =
10 2 3 5 R
T
A 1
10
V 10
R
E
I
T
=
Ω
= =
I
1
= 1 A I
T
R
1
= 1 A x 5
Ω
= 5 V
I
2
= 1 A I
T
R
2
= 1 A x 3
Ω
= 3 V
I
3
= 1 A I
T
R
3
= 1 A x 2
Ω
= 2 V
Total IR Drop = 10 V
OR
IR
T
= 1 A x 10
Ω
= 10 V
E
T
= 10 V
Note that Kirchhoff’s Voltage Law is fulfilled.