1. What is Reliability Calculation?

Reliability calculation using the exponential formula estimates the probability that a system or component will perform its intended function without failure for a specified period of time under stated conditions.

2. How Does the Calculator Work?

The calculator uses the reliability equation:

Where:

• \( R \) — Reliability (probability of success)
• \( \lambda \) — Failure rate (failures per unit time)
• \( t \) — Time period
• \( e \) — Base of natural logarithm (approximately 2.71828)

Explanation: The equation models the probability that a system will operate without failure for time t, assuming a constant failure rate λ.

3. Importance of Reliability Calculation

Details: Reliability calculations are essential for system design, maintenance planning, risk assessment, and quality control in engineering and manufacturing.

4. Using the Calculator

Tips: Enter failure rate in failures per hour (1/h) and time in hours (h). Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What does the reliability value represent?
A: The reliability value R represents the probability that a component or system will function without failure for the specified time period.

Q2: What is a typical range for failure rates?
A: Failure rates vary widely by component type, from very low rates (e.g., 0.000001/h for high-reliability components) to higher rates for less reliable components.

Q3: When is the exponential reliability model appropriate?
A: This model is appropriate when failure rates are constant over time, which is typically during the "useful life" period of a product's life cycle.

Q4: What are the limitations of this model?
A: The model assumes constant failure rate, which may not account for early failures (infant mortality) or wear-out failures at end of life.

Q5: How is reliability related to MTBF?
A: Mean Time Between Failures (MTBF) is the reciprocal of the failure rate (MTBF = 1/λ). For constant failure rates, reliability R = e^(-t/MTBF).