Reliability Analysis

Running head: RELIABILITY ANALYSIS
RELIABILITY ANALYSIS
Name of the Student
Name of the University
Author Note

1RELIABILITY ANALYSIS
Task T1:
The projection system is comprised of Lamp (L), internal electronics (I) and connection to
mains power (C). The reliability blocks will be connected in series as failure of any
component implies the failure of total projection system.
The failure rate per hour of the projector lamp as calculated in excel is given by the formula
Failure rate per hour = 1/MTTF
MTTF = mean time between failure = total hours of operation/total number of units failed =
405.989 (correct up to 3 decimal places).
Here, MTTF is considered instead of MTBF (mean time between failures) as bulbs are not
repaired or replaced during the test of 1200 lamps in 1000 hours.
Hence, Failure rate per hour = 1/405.989 = 0.002 (correct up to 3 decimal places).
The failure rates of Internal electronic per hours is 0.00015 and the failure rate of mains
power cable is 0.00010.

2RELIABILITY ANALYSIS
Figure: Reliability block diagram of entire system
Now, the reliability of the system is calculated by the following procedure.
The probability of failure of system = (((0.00005 + 0.00018)*0.00008*0.00008 +
0.00005*0.00008*(0.0003+0.0005*0.001)*0.00008 + 0.00005)*0.00002*0.0001*0.00008 +
0.0001)*0.00015*0.002 = 3*10^(-11)
Reliability of the system = 1 – Probability of failure of the system = 1 - 3*10^(-11) ~1.
Hence, the reliability of the system is almost equal to 100%.
It is assumed in the failure rate calculation that the lamps are not replaced or repaired in the
actual projection system like the conditions of testing phase.
Task T2: