Reverse Erlang B? This topic has 1 reply, 1 voice, and was last updated 9 years, 9 months ago by pix. Viewing 2 posts - 1 through 2 (of 2 total) Author Posts 19th December 2013 at 21:25 #69410 Wyatt BikerGuest I want to guesstimate how many calls at peak a PBX can handle based on the number of devices on the PBX. Lets say it is 2,000 extensions. Calls can be internal and external. I don’t have easy access to CDR. Is there some method I can use? Thanks 20th December 2013 at 15:37 #69411 pixGuest you can use a basic erlang B calculator, and get any result you need. What’s the congestion rate that’s allowed in yuour PABX ? You can find several online erlang calculators, and even excel macros. Here is one which does not provide “reverse” results. So you can just try different erlangs, until you reach the number of lines = 2000. http://www.cas.mcmaster.ca/~qiao/publications/erlang/newerlang.html#calculator Erlangs – rho = 1894[input] Grade of Service – P(c) = 0.0005 [input] (=0.05% congestion) Result: Capacity/Num of Lines = 2000 [output] But anyway, you can find anything on the net, just keep looking 🙂 Cheers pix Author Posts Viewing 2 posts - 1 through 2 (of 2 total) The forum ‘Telecom Design’ is closed to new topics and replies.