1. What is Paschen's Law?

Paschen's Law describes the relationship between breakdown voltage, gas pressure, and electrode distance in a gas discharge. It states that the breakdown voltage is a function of the product of pressure and distance (p·d).

2. How Does the Calculator Work?

The calculator uses Paschen's Law equation:

Where:

• \( V \) — Breakdown voltage (V)
• \( p \) — Gas pressure (torr)
• \( d \) — Distance between electrodes (cm)
• \( A \) — Constant related to gas properties
• \( B \) — Constant related to gas properties

Explanation: The equation shows that breakdown voltage depends on the product of pressure and distance, with constants A and B specific to the gas type.

3. Importance of Breakdown Voltage Calculation

Details: Accurate breakdown voltage calculation is crucial for designing electrical insulation systems, gas-filled devices, and high-voltage equipment to prevent unexpected electrical discharges.

4. Using the Calculator

Tips: Enter pressure in torr, distance in cm, and appropriate A and B constants for the specific gas. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What are typical values for constants A and B?
A: For air: A ≈ 15 cm⁻¹·torr⁻¹, B ≈ 365 V·cm⁻¹·torr⁻¹. Values vary for different gases.

Q2: Why does breakdown voltage have a minimum value?
A: Paschen curve shows a minimum breakdown voltage at a specific p·d product, below which voltage increases due to fewer collisions.

Q3: What are the limitations of Paschen's Law?
A: The law assumes uniform electric field, constant temperature, and may not accurately predict breakdown at very small gaps or high pressures.

Q4: How does gas composition affect breakdown voltage?
A: Different gases have different ionization potentials and electron attachment coefficients, leading to different A and B constants.

Q5: Can this calculator be used for all gases?
A: Yes, but you must use the appropriate A and B constants for the specific gas being analyzed.