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does a loop start trunk on a MM711 board put out voltage like a CO?

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rejackson

IS-IT--Management
Oct 4, 2005
627
US
I am dealing with a Door King 1812 gate controller connected to a trunk on a MM711 in a G450. A TAC is used to access the gate and give it commands to open, close, etc. A button on the gate box calls in to a cover group through incoming call treatment on the trunk. The Avaya trunk is set up wats and loop start. The trunk shows disconnected most of the time but after a reset it comes up. Calls out to the gate get a busy and calls in ring but cannot be answered. This use to work until they replaced the Door King unit and I don't think they have it set up right. The quote below is from the door king manual. I am trying to understand if I should tell them to use PHONE mode or INTERCOM mode based on how the trunk is configured.

"The 1812 is normally connected in series with a residents incoming phone line, which supplies a constant source of DC voltage. When the 1812 is connected in this manner, program the unit for PHONE mode.
If the 1812 is to be connected to an open C.O. (Central Office) port on a key type telephone system, or if the 1812 is connected directly to another telephone without a C.O. line, program the unit for INTERCOM mode. When programmed in intercom mode, the 1812 will supply the constant DC voltage necessary for operation and will disconnect the PHIN terminals from the circuit since these are not used in intercom mode."

As always, thanks for listening

REJ
 
loop-start trunks are just like your "2 wire tip/ring copper" home phone line
an analog station from CM also provides voltage, dial-tone, ringing current to make an analog phone work.
Code:
       1.  Basic_Electrical_(DC)_Parameters

       1.1  CO_Trunk+

                    CO Ground-Start Trunk Specifications
                        Parameter                    Minimum   Maximum
       Loop Current (Active State)                    20mA      90mA
       TIP to Ground Voltage From CO (IDLE State)      0V#      105V#
       TIP to Ground Voltage On Port (IDLE State)    -42.5V    -52.5V
       RING to Ground Voltage From CO (IDLE State)    -16V      -105V
       RING to Ground Voltage On Port (IDLE State)     **        **

                         CO Loop-Start Trunk Specifications
                           Parameter                        Minimum   Maximum
       Loop Current (Active State)                           20mA      90mA
       TIP or RING to Ground Voltage From CO (IDLE State)   Note 2    Note 2
       TIP or RING to Ground Voltage On Port (IDLE State)     **        **
       TIP to RING Voltage From CO (IDLE State)               0V       105V

A great teacher, does not provide answers, but methods to teach others "How and where to find the answers"

bsh

40 years Bell, AT&T, Lucent, Avaya
Tier 3 for 30 years and counting
[URL unfurl="true"]http://bshtele.com[/url]
 
So I guess that means I need the gate box to send the constant DC voltage?
 
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