atcomsystems.ca/forum Forums General General Telephone & Systems Information Centrex

Hi I have a customer who wants to change from centrex to a pots. They have 21 centrex CCT's. I am quoting a new system with a PRI. How do I figure out how many channels they will need?
Thanks

I would think that a full 23 Channel PRI would be suffice unless they do alot of off-net transferring. I'm guessing that the 21 Centrex numbers are in one location (again guessing) so if they are all on the same system the system would be handling the transfer not centrex but if they are sending these to other numbers in other locations, unless of coarse you are putting remote IP phones, this would take 2 trunks(channels) to transfer the call out.

Hope that helped ya!

Gary

Without a little more info, every reply will be an educated guess. A 23 channel PRI will replace the 21 Centrex lines, but, not knowing how they use the Centrex lines limits our ability to give you advice.

If the client is doing a lot of out of system transferring, then a second PRI might be in order. If all they used the Centrex for was to transfer between phones in the office, then, depending on number of users and traffic volume, a PRI might be over kill.

Here in Pittsburgh, there were, at one time, a great many corporate offices for national and multi-national companies. Centrex made sense, then, because a call arriving in Pittsburgh might be directed to, as an example, Chicago. Hookswitch flash, dial number and hang up....Done. Transfer complete. Today, nearly all companies are better served by a PBX or Hybrid Key System as 800 number direction for region is standard so that transferring calls out of office is much less and can be handled by system transfer.

Rcaman

Thanks for the reply I should have supplied more info.The customer is the local Co-Op admin office. The telco sold them centrex because they used to do 4 digit dialing to call to different sites, and it is more money in trhe telco's pocket. They dont do 4 digit dialing any more so they want to drop the centrex and save a few dollars. I had thought that a 12 to 15 channel PRI would be enough. They hope to keep the same numbers. The telco can be difficult to deal with so we will see. Yes all the 21 centrex numbers are on one site and they dont transfer off site. The reason for the PRI is that they want to keep the same numbers some of the staff have had the same number for years

I am not familiar with Canadian telco regulations, so I don't have a good answer for you. Here in the states, most LEC will port the numbers over and if they will not, the client can request RCF and that will forward the numbers to the new number for a year. Depending on the number of people using the system, the 20% rule usually works unless there is a call center and a lot of traffic.

Rcaman

I don't know about Alberta, but here Bell can change Pots to Centrex or vise verso without losing the numbers.