To tackle this problem, we need to break it down into a few manageable parts. We are given the number of failures, the total number of devices, the time period, and the mean downtime. From this information, we can calculate the Mean Time Between Failures (MTBF) and the Mean Failure Rate (MFR).
Understanding the Given Data
Here’s what we have:
- Failures recorded: 150
- Total devices: 200
- Time period: 1.5 years
- Mean downtime: 0.002 years
Calculating Mean Time Between Failures (MTBF)
MTBF is a measure of how long a device operates before it fails. It can be calculated using the formula:
MTBF = Total Operating Time / Number of Failures
First, we need to determine the total operating time for all devices over the given period. Since we have 200 devices operating for 1.5 years, the total operating time is:
Total Operating Time = Number of Devices × Time Period
Total Operating Time = 200 devices × 1.5 years = 300 device-years
Now, we can plug this into the MTBF formula:
MTBF = 300 device-years / 150 failures = 2 years
Finding the Mean Failure Rate (MFR)
The Mean Failure Rate indicates how often failures occur and can be calculated using the formula:
MFR = Number of Failures / Total Operating Time
We already calculated the total operating time as 300 device-years. Now we can find the MFR:
MFR = 150 failures / 300 device-years = 0.5 failures per device-year
Summary of Results
To summarize our findings:
- Mean Time Between Failures (MTBF): 2 years
- Mean Failure Rate (MFR): 0.5 failures per device-year
These metrics are crucial for understanding the reliability of the devices in question. A higher MTBF indicates better reliability, while a lower MFR suggests fewer failures over time. If you have any further questions or need clarification on any of these calculations, feel free to ask!