Telos NX12 Integration with a PBX, Using Isdn, Using Pots, USA and Canada, Outside of the USA

10  Section 2

2.6 Integration with a PBX

The Nx12 will usually be used independently of any other phone system in your facility. But it is possible to have one or more of the lines come off another phone system. Depending upon the PBX and your preferences, this can be either ISDN BRI or POTS.

You might be able to save money by using a T1/E1 or ISDN PRI as your Telco link and having the PBX generate local ISDN BRI or POTS lines for the Nx12.

Consider having at least one line directly from the Telco to keep your Nx12 up and running even if the PBX or its Telco connection goes down.

Using ISDN

Telos equipment has been used satisfactorily using BRI off the following PBX Switches:

USA and Canada

♦♦ Nortel Meridian Option 11, 2 wire (U interface). Protocol ID = 6. [user report] ♦♦ Lucent/Avaya Definity, 2 wire (U interface) [user report]

♦♦ Avaya IP Office (must use Q.931 mu setting on Telos) [user report]

Outside of the USA

♦♦ Siemens HiCom series, 4 wire (S interface) [user report]

ETS300 Euro-ISDN is available from many PBX systems outside the USA and compatibility is generally good.

Unless your PBX is listed above, its support of US/Canada National ISDN-1 is not certain. We recommend you arrange a test for compatibility before committing to the purchase of the PBX ISDN module.

Contact Telos support for the latest information, or to report your experiences with other switches.

Using POTS

Most PBX or VoIP telephone systems can provide analog ports for analog equipment such as modems and fax machines. You will need such ports to connect a POTS Nx12 to a PBX.

With all calls passing through the PBX, calls into the main station number can be transferred over to the on-air system. If the PBX supports ‘hook flash transfer’ on the analog ports, you can even use this feature of the Nx12 to transfer lines from the on-air system back to the PBX. This can also be done if the PBX and Nx12 share Centrex lines.

A few years ago, we advised that hybrid performance was best when equipment was connected directly to the lines from the Telco. Today, this is not always true. If the PBX is connected to the Telco using digital lines (such as T1, E1, PRI, S2M, etc), performance through a digital PBX will generally be better than direct connections to copper analog circuits. This is particularly so if you are located a significant distance from the Telco central office.

The biggest variable when connecting to a PBX analog port is the quality of the analog port. We have found that many PBX manufacturers offer more than one analog port option. The better port can usually be distinguished by its higher cost, and the fact that it may offer 48 volts rather than 24 volts. The Nx12 will work with either voltage; however experience has shown that the

48-volt version usually has better quality transformers and other components, resulting in better hybrid performance.