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KSU MICS 7.0 - ALL lines are supervised

When the far end terminates the call, whether the call is in the IVR or placed on hold, it will not disconnect. The service is delivered via pair gain (SLC2000 / DMS-100 switch) and according to the CLEC we're closer to that equipment than normal. For that reason, they instructed us to change our programming for a "short CO" which I've done but that has not solved the problem. I had a similar issue in the past involving pair gain and it took moving the service to straight copper to work. I've done that here as well with (1) line but it's still not disconnecting. I then had the CLEC field tech take the following voltage and loop current readings:

Readings from line via pair gain:
On-hook 52.4V / 35.1ma
Off-hook 6.6V / 14.2ma
Far end terminates call returns 52.4V / 35.1ma

Readings from line via copper:
On-hook 53.4V / 27.7ma
Off-hook 6.0V / 12.8ma
Far end terminates call returns 53.0V / 27.7ma

I have also conducted several tests w/ the field tech monitoring incoming calls with their butt-set going into the IVR. When I hang-up the call, the IVR continues to play but you also hear the dialtone return to the line. At the same time, I had the CLEC switch tech monitoring the call telling me when the call connected, when it released, and when dialtone was returned.

Please let me know if you need additional information to offer up your suggestions.

Dial tone being returned indicates that loop supervision is not being sent by the CO or that it is not being repeated by the pair gain equipment.

Here are a few easy ways to detect where the fault lies:

The easiest way to test for this is to pull the CO line from a call in progress. If the system drops the call, then you will know that the system is fine and that the telco isn't sending you the open loop supervision for disconnect. If the IVR stays connected, then you have an equipment or programming problem on your end.

Place a line on hold (without dialing anything). If it drops off from hold after about 20 seconds, then you definitely are receiving the disconnect supervision from the telco. If it stays on hold, then you are not receiving it.

You may also want to just place a toner in the off position across the line. The LED on it should go out for about half a second shortly after the far-end party hangs up. If it stays lit, there's your sign. The telco isn't sending the open loop.

My vote is that you are not receiving loop supervision from the telco. This happens far too often and you will have a hard time getting them to admit it. You will have much better luck getting someone in the telco's repair department to understand what you are seeking than contacting their business office.

First be sure disconnect supervision is turn on in LINES programming.

Do Ed's tests next. Also If you monitor the line with a butt set, when the remote disconnects, you will hear the hum of the CO DS signal 10-20 secs after hang up.

Readings from line via copper:
On-hook 53.4V / 27.7ma
Off-hook 6.0V / 12.8ma
Far end terminates call returns 53.0V / 27.7ma

When the far end terminates you should go to 0v then back up to around 50. Is that what they see ir dies it just go back to 50 if so then Telco is not providing the Dissconnect.

Surprise, Surprise

I received a call back from the ILEC switch tech. Although he claims nothing was changed, he did check the DMS-100 switch parameters for the COD feature. They should be set to bell standard of 80 (800ms)and according to him they were. He asked me to test again. I would you know it the lines start releasing almost immediately after terminating the call.

ON the MICS the It needs a loop reversal disconnect.

I have had it to where the CLEC equipment sending the wrong disconnect type and had to program the unit to send a different disconnect supervision.