# Trunk Circuit Descriptor - Loop Tie

## Purpose

The Loop Tie Trunk Circuit Descriptor form completes the basic definition of loop tie trunk characteristics. With this form, trunk signaling and timing parameters are set for groups of loop tie trunk circuits. The circuit descriptor numbers in this form are referred to in the Analog Trunks form.

To complete this form, enter the required descriptor numbers in each column and select the corresponding values.

Use this form when performing the following tasks:

- Tie Trunk Support Programming

NOTE: The operating characteristics for all trunks are defined by the respective trunk circuit descriptor form. There are 32 trunk circuit descriptor numbers available. These must be shared between all trunks in the system. As well, each circuit descriptor number assigned must be unique. MITEL recommends that the circuit descriptor numbers be allocated to each type of trunk in blocks. For example, CO trunks may be allocated circuit descriptor numbered 1 through 4, E&M trunks numbered 5 through 12, DS1 DID trunks numbered 13 through 21, and so on.

## Field Descriptions

Parameter | Description | Default Value
Number | Enter a number from 1 to 31 to uniquely reference the Loop Tie trunk characteristics in the Analog Trunks form. | Blank
Release Acknowledge Timer | Enter a value between "40" and "2400" in increments of 1 unit, where 1 unit = 50 milliseconds. The range in milliseconds is "2000" to "120,000". This timer specifies the amount of time the system waits for a release acknowledgement from the far-end. | 80 units (4000 ms)
Address Signalling | Select "Loop" if loop signaling is to be provided by the trunk circuit, "DTMF" if DTMF signaling is to be provided by the trunk circuit, or "Battery" if Battery and Ground loop signaling is used. NOTE: When systems are connected via T1/D4, the address signaling must match on either end of the connection. If one end is programmed as Loop and the other as DTMF, the dialed digits will not be translated by the receiving system, and the call will fail. | Loop
Disconnect Timer | Enter the duration of the disconnect signal timer. Allowed values are from "150" to "300" milliseconds, in 50 millisecond increments. This value defines the minimum acceptable duration of a disconnect signal from the far end. | 300 ms
Incoming Start Type | Select "Wink" if the trunk is wink start on incoming calls, "Delay" if the trunk is delay dial start on incoming calls, or "Immediate" if the trunk is immediate start on incoming calls which means that digits are outpulsed immediately following seizure. | Wink
Incoming Dial/Outgoing Auto | Select "Yes" if the trunk is dial-in for incoming operation, and attendant-handled for outgoing operation. Select "No" to cause the trunk to use 2-way loop signaling. This option is usually selected when the far end is a manual PABX. | No
Dial Tone on Incoming Seize | Select "Yes"to return dial tone by the system when the trunk is seized by the far end. Select "No" to indicate that dial tone will not be returned on a seize. | No
Outpulse Delay Timer | Enter a value between "100" and "2000" milliseconds, in increments of 50 milliseconds, to define the duration of the delay before outpulsing commences after a seizure. NOTE: Outpulsing could commence several hundred milliseconds after the programmed duration. Only the minimum duration is guaranteed. | 800 ms
Outgoing Start Type | Select "Wink" if the trunk should provide wink start signaling on outgoing calls, "Delay" if the trunk should provide delay dial (without integrity check) signaling on outgoing calls, or "Immediate" if the trunk should provide immediate signaling on outgoing calls. Select "Delay Integ" to provide delay dial with integrity checking, which indicates that the system must wait for a delay dial signal from the far end before outpulsing. | Wink
Supervision Timer | Enter the duration of the supervision timer. Values can range from 200 to 12750 ms. 200 to 1000 milliseconds applies to "Immediate" trunks. 200 to 12750 milliseconds applies "Wink" to trunks. 4500 to 12750 milliseconds applies to "Delay" and "Delay Integ" trunks. Values increment by 50 ms. This timer specifies the expected duration of a supervision signal from the far end. | 200 ms
Maximum Wink Timer | Enter the maximum duration of the wink signal. Values range from 300 to 4000 ms. 300 to 450 milliseconds is the range for immediate, wink start and delay dial trunks. 300 to 4000 ms can apply for delay dial with integrity check. Values increment by 50 ms. | 400 ms
Minimum Wink Timer | Enter a value between "50" and "150" milliseconds,in increments of 50 milliseconds to define the minimum duration of the wink signal. | 100 ms
Guard Timer | Enter a value between "100" and "1000" milliseconds, in increments of 50 milliseconds to define the guard time. This timer specifies the amount of time a trunk will be unavailable for seizure following a release, to allow the trunk to clear before reseizing. | 500 ms
Fake Answer Supervision After Outpulsing | This option is used to complete the audio connection after outpulsing if the trunk does not provide Answer Supervision. Select "Yes" if Answer Supervision should be provided immediately after outpulsing. Select "No" to cause the system to wait for Answer Supervision from the far end, if any is provided. | No
Ignore Answer Supervision | Select "Yes" if the system should ignore answer supervision from the far-end. Answer Supervision is generated by using times and/or tone detectors. Select "No" to indicate that Answer Supervision from the far end is to be accepted. | No
Release Supervision Expected | Select "Yes" if the trunk circuits are expecting Release Supervision from the far end. Select "No" to indicate that the trunk circuits do not provide Release Supervision. The system will not allow two trunks designated as "No Release Supervision Expected" to be connected together. | Yes
Audio Inhibit Until Answer Supervision | This option prevents a DTMF receiver, in linesplit mode, from being connected between the originating party and the outgoing trunk during the digit outpulsing phase of the call processing cycle. Used for sites that are tied to very sensitive central offices or remote systems. When the option is chosen, the audio path will be fully connected and the two parties will be able to talk only after the answer supervision has taken place. Select "Yes" if a DTMF receiver, in linesplit mode, is NOT to be connected between the originating party and the outgoing trunk during digit outpulsing. Select "No" if a DTMF receiver, in linesplit mode, IS to be connected between the originating party and the outgoing trunk during digit outpulsing. | Yes
Far-End Connection | Not applicable to this release. | Main PBX
High Loss Option | Not applicable to this release. | No
Balance Network Setting | Select "600" if the load presented to the trunk port is resistive, (loaded cable, broadband system), or "Complex" if the load is capacitive (long unloaded cable). If necessary, the best option can be determined by optimizing the echo return loss as seen from an OPS or ONS connection. | 600
Drop Digit Rcvr for Outgoing Audio Before Ans Sup | This option allows DTMF digits to be sent from a telephone to the CO without having to wait for or fake answer supervision. It also allows the system to provide exact call detail through SMDR by using the answer supervision signals provided by the CO. Select "Yes" for credit or calling card calls, calls that require pin numbers, and equal access calls. For example, if the CO recognizes a calling card call, it will send either a tone or recorded message. After the user enters a valid card number, the call proceeds and answer supervision is returned when the called party answers. | No
Flash Timer | Enter a value between "200" and "700" milliseconds in increments of 50 milliseconds. This timer specifies the duration of the single trunk flash or each of the flashes for a double trunk flash. For a double flash, the time between flashes is hard-coded at one second. | 300 ms