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Private Line Automatic Ringdown Circuits

Private Line Automatic Ringdown Circuits

Private Line Automatic Ringdown Circuits

When Private Line Automatic Ringdown Circuits (PLAR) are delivered via channels on a T1, must they first be broken out into individual analog circuits by a Channel Bank before being connected to a Communication Manager controlled system, or can the T1 be terminated directly onto a DS1 card with the ringdowns on the channels still being handled correctly by the PBX?   

RE: Private Line Automatic Ringdown Circuits

Last I worked on PLAR circuits I received them on a DS1 and then defined the DS0's to sets as Personal CO Lines.  Once the PCO's were defined I bridged them to other sets.  

This was a while ago I have no samples to share Sorry

Hope this helps

1a2 to ip I seen it all

RE: Private Line Automatic Ringdown Circuits

Thanks.  Seems like this should work, since all that is required is that the CO see a line (in this case on one of the T1 channels) go off hook. The CO should then automatically ring the far end.  The Avaya can handle the T1 channels directly when they're programmed to look like analog trunks and dialtone is expected, so why not when they are PLAR.

RE: Private Line Automatic Ringdown Circuits

The T1 must be configured for "CAS", this is the only way an AVAYA PBX can support ARDs delivered via a T1.  We have done this in the UK, where they are available.  I have not seen any every delivered this way in the U.S., we always use a channel bank and interface them via CO trunks in the US, because of lack of CAS supported T1's.

If you order your circuit through IPC's circuit group, that would be one of the only possibilitys of getting a CAS T1 circuit in the US


AVAYA Certified Specialist

RE: Private Line Automatic Ringdown Circuits

It's been a while but What you are asking for is ARD (Auto Ring Down) My system does not allow me to try this.  Try setting the PCO as a hot line ???


1a2 to ip I seen it all

RE: Private Line Automatic Ringdown Circuits

1a22ip, to support ARDs, delivered via a T1, the signalling on the T1 must be set to "CAS", otherwise it won't work.  We've tried, and this is the only way to get it working.  This is on a UK switch...

display ds1 002v4
                                DS1 CIRCUIT PACK

            Location: 002V4                           Name: LONLON096242
            Bit Rate: 2.048                    Line Coding: hdb3

      Signaling Mode: CAS

        Interconnect: pbx                 Country Protocol: 10

Interface Companding: alaw                             CRC? n
           Idle Code: 01010100

      Slip Detection? y                 Near-end CSU Type: other

   Echo Cancellation? n


Then you add the trunks as TIE trunks, group type TIE, and put the channel as the ringdown, such as 002V401.  We then send these to X ported stations and bridge them on phones, this way we can control if the ringdown actually rings on the phones, some traders only want to "see" them, no hear them...



AVAYA Certified Specialist

RE: Private Line Automatic Ringdown Circuits

Thought standard voice T1's use CAS signaling while CCS is normally associated with an ISDN PRI, so I'm a bit confused about not being able to get a CAS T1 here.

Some months back we connected an IPC (WestCom) T1 to a Mitel 3300ICP with no problem. It had a full 24-channels, with no channel reserved for signaling as it would have been if it were CCS rather than CAS.   

RE: Private Line Automatic Ringdown Circuits

Yes libellis, pretty much the only company that can deliver a CAS T1 is IPC (Westcom).  There is no signalling channel used, this is NOT a PRI, it is a T1 T1, with CAS signalling.  That T1 that you received from Westcom was a CAS T1, I would bet you.


AVAYA Certified Specialist

RE: Private Line Automatic Ringdown Circuits

Thanks Mitch672. Any T1 for this application would likely come from IPC or someone else (is there anybody left after IPC has purchased most of its competitors) able to deliver with the correct signaling format.

The good news is that it can be done on the Avaya.


RE: Private Line Automatic Ringdown Circuits

The T1 in NY (USA) was set to Robbed Bit.  When I had PLAR this was the setting.  But I had no Siginalling on the circuit.  It was call a Hoot & Holler line (up and active to speakers). Mitch is right that this will only work on a NON PRI T1 span.  I never seen PLAR or ARD on PRI.  It like mixing Apples and Oranges.  

Again this was ages ago.  

Hoots and ring downs and B*TCH Boxes OH My

1a2 to ip I seen it all

RE: Private Line Automatic Ringdown Circuits

I appreciated both your inputs 1a22ip and Mitch672.

I was aware that CAS is the signaling required for the PLAR T1 and that PLAR's are not delivered over a PRI, but I think I partially misinterpreted Mitch672's initial reply, and my subsequent response reinforced that impression. Anyway, "all's well that ends well". Thanks again.

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