[RE-wrenches] MTBF

[holtek at sbcglobal.net]

I am working on a residential project that seems perfect for the Enphase product (long array to interconnect point run). Researching the product, I came across one of their website videos (nicely done) claiming an "MTBF of 119 years" without any explanation as to what that actually means - that is - how did they arrive at that assumption/prediction. I googled "mean time between failures".  Got this - http://www.ptsdcs.com/whitepapers/57.pdf  - a white paper that briefly explains different methods to predict or assume system and or component failures/reliability. Interesting. The conclusion of this white paper:
MTBF is a "buzz word" commonly used in the IT industry. Numbers are thrown around without an

understanding of what they truly represent. While MTBF is an indication of reliability, it does not represent

the expected service life of the product. Ultimately an MTBF value is meaningless if failure is undefined and

assumptions are unrealistic or altogether missing. (emphasis mine).

So my question is this: Are any manufacturers that use MTBF as a selling point willing to disclose how these values were obtained? Not picking on Enphase....I will contact them with to ask. IMHO, with the new stuff that will be thrown at us over the coming years, we should expect real numbers from anyone using MTBF to tout their stuff. 

Stepping off soap box. 

Holt E. Kelly
Holtek Fireplace & Solar Products
500 Jewell Dr.
Waco TX. 76712
254-751-9111
www.holteksolar.com
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