AC Resistance Example
Understanding Resistance Measurement in AC Circuits
Introduction
This page explains why measuring current from only one wire in an AC circuit can lead to incorrect resistance and power calculations.
We'll explore the math and provide a basic calculator to demonstrate these differences.
Key Formulas
-
Ohm's Law:
R = V / I
-
Total Current:
I_total = V / R
-
Power:
P = V * I
-
Per Wire Current (Balanced Split):
I_per_wire = I_total / 2
Example Setup
We use the following setup for calculations:
- Load Resistance: 1 Ω
- Amplifier Voltage (RMS): 40 V
- Total Current: \( I_total = 40 A \)
- Balanced Split: Each wire carries 20 A.
Comparison Table
Measurement Setup | Voltage (V) | Current (I) | Resistance (R) | Power (P) |
---|---|---|---|---|
Both Positives Clamped | 40 V | 40 A | 1 Ω | 1600 W |
One Positive Clamped | 40 V | 20 A | 2 Ω | 800 W |
Basic Calculators
Calculator 1: Enter values below to calculate resistance and power:
Results:
Resistance: N/A
Power: N/A
Calculator 2: Enter values below to calculate resistance and power:
Results:
Resistance: N/A
Power: N/A