Can anyone please tell me if there is an 'easy' answer to this. I have an electronic sensor with a rated MTBF of 47,500 hours. I understand I can improve the MTBF by applying a factor for burn-in testing, be it 8, 12 or 24 hours. Is there a simple factor I can apply as I need to increase the MTBF figure by about 10%.

I would say, not really. Reliability Growth is what you need to carry out to establish if there is any growth and if so, what growth.

MTBF can be and is often misued. You need to be careful with it as it implies that the sensor can be repaired and used again. If this is the case, the life becomes a little more difficult in terms of calculating MTBF, sicne you need to take into account that the repair will never restorethe sensor to as 'good as new'.

In addition, you may come up with a point estimate for reliability such as 500 hours MTBF, but you still don't know the uderlying distribution. (Most folk assume a constant failure rate for simplicity and calculate MTTF/MTBF using the usual, famous reliability equation)

If it is dispensible at failure then MTTF or mean-time-to-fail is usually used.

Here is a very good website. There is also a discussion forum on here.

http://www.weibull.com

If I can help you further, drop me a line at davidrobson@iee.org

Edited: 22 December 2010 at 01:13 PM by dvaidr