Hi All,
I am calculating the internal rate of return (IRR) for a WiFi project involving a large number of MikroTik Routerboards (mainly RB411 family). What is the average service life or Mean Time Between Failure (MTBF) of these boards?
I was going to use 10 years as a guess. Does anyone have hard numbers for this statistic?
They will be installed outside in weatherproof enclosures in the Pacific Northwest United States.
Thanks!
we haven’t done any certified tests officially, so my guess would be as good as yours 
maybe others have experience and could share?
MTBF for same type each RB batch can be very different. It’s related with when this RB is made, where and how large is production bath and some other consedirations.
Yes, that is understandable. There are tolerances and acceptable variances for any product. But isn’t that what the MEAN means in MTBF? 
However, I am trying to follow the principle of Conservatism. What would you guess for the shortest life of a batch of RB411’s?
I would calculate your ROR around a 3 year replacement cycle, this will ensure your network remains up to date. Sure you may get 5 or more years out of it, but if you do your calculations on 3 years than any extra time it keeps running for over this is for free.
My 2c
Much appreciated nz_monkey.
I’m not an accountant, but I’m guessing this would constrain the depreciation schedule to 3 years also.
Ciao!
Yes, it would I am not sure of the depreciation laws in your country but in NZ they are rather favorable in regard to IT equipment allowing it to be depreciated to almost $0 value in 1.5 years.
It may be a good idea to join WISPA if you are not already a member, I am sure other members will be able to give you advice on what business model works best within the federal and state tax laws.