T1 bi-polar violation qualified alarm

A bi-polar violation (BPV) condition has occurred. The BPV may be caused by a defective telecommunication line cable, defective hardware, or incompatible line coding between Blueworx Voice Response and the terminating equipment (CSU, PABX, channel bank, and so on).

Check that the Blueworx Voice Response T1 line code (AMI ZCS or B8ZS) matches the T1 line code of the terminating equipment. Determine the Blueworx Voice Response T1 Remote Alarm Format by clicking Configuration... System Configuration... Trunk Interface and selecting the trunk concerned. AMI/ZCS is more common than B8ZS which is normally used for clear channel operation and ISDN. ZCS (zero-code suppression) and B8ZS (bi-polar eight zero substitution) are two ways of ensuring an adequate density of "ones" in the T1 digital signal. B8ZS deliberately introduces bi-polar violations at the transmitting end and a high BPV error rate occurs unless the receiving end is configured to decode them. If the configurations match, test the telecommunication line cable. Check the telecommunication cables and connections to the network. Check that all cable connectors are firmly seated. Run the diagnostics described in the Problem Determination information. If the cable and Blueworx Voice Response are OK, the problem is with the terminating equipment or the transmission path beyond the line cable. Call Blueworx Support with the details and results of all tests you have tried.




Log, System Monitor