FXO/DPT 12-Channel Card

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Operational Description

The Foreign Exchange Office (FXO) and Dial Pulse Termination (DPT) 12-channel card sinks battery current and detects ringing voltage provided by a connected Central Office (CO) line or PBX extension. Thus, the FXO provides a method to transport dial tone lines to a remote location, extending support of all PBX features such as call transfer, direct extension dialing, hunt groups and conferencing.

When configured as a DPT interface, this channel card sinks and detects both forward and reverse current, replicating the conditions coming from the remote CO Direct Inward Dial (DID) lines. DID service provides the dialed digits necessary to ring a telephone extension directly without requiring a dedicated telephone line for that particular number. Additionally, the DPT interface is useful in terminating Dialed Number Information Service (DNIS) for 800 numbers, allowing Automatic Call Distributors (ACDs) and Voice Mail Systems to provide information to the receiver that is specific to the 800 number dialed.

The FXO-DPT supports Carrier Access' proprietary 2-wire Calling Party Disconnect (CPD) when used with a Carrier Access' FXS card on the far end of the T1 line. This feature provides calling party supervision and prevents hung lines in PBX, IVR, and key systems.

The card also converts FXO loop start (with reverse batter y) to E&M immediate start, thereby providing DPT functionality with ringing detection. This feature is frequently used when inter facing with many CTI-based applications.

Physical Description

The FXO/DPT measures 7.8" X 13.6" and slides into the back of the Access Bank I, Access Bank II, or Access Exchange family of T1 Voice and Data Multiplexers.

FXO/DPT Card Features and Advantages

Features Advantages

FXO loop or ground-start is switch selectable for each channel Supports both start types

DPT functionality Switch selectable on a per-card basis

Supports DID and DNS carrier services Allows common business voice services

FXO loop start to E&M immediate conversion Provides DPT functionality with ringing detection

Channel status LEDs show call progress "At-a-glance" status determination

US Grade A" telephone line quality Analog loop provides 15,000 ft. range

Full compatibility with V.34 & V.90 modems Greater versatility in serving major modem type

Fuseless over voltage and overcurrent safety protection Prevents voltage-related damage to card

Carrier Access patented automatic impedance balancing Boosts performance because card adapts to line conditions

Passes caller-ID and other CLASS® services for CO line connections

Technical Specifications

This FXO/DPT card adheres to applicable parts of: Bellcore Technical Reference TR-NWT-000057 "Functional Criteria for Digital Loop Carrier Systems," Issue 2 of January 1993, ANSI/EIA/TIA-464-A-89 "Public Branch Exchange (PBX) Switching Equipment for Voiceband Applications," Issue 1 of February 1989, FCC Part 68 regarding PSTN connection, FCC Part 15 regarding Class A radiated emissions control, and UL 1459, NEC 1996, and CSA safety approvals.

FXO Transmission Performance

Return Loss: ERL > 28dB, SRL > 20dB with respect to 900W +2.16µF
Transhybrid Loss: ERL > 28dB, SRL > 20dB with respect to 900W +2.16µF
Idle Noise: A/D<15dBrnCO, D/A, 10dBrnCO
Crosstalk Coupling: <80dB at 0dBm0
Signal/Distortion: >45dB with 1004Hz, 0dBm0 input
Overload: +3dBm/900W
Frequency Response: +0.25dB, -1.0dB from 300 to 3400Hz
Encoding: µ-Law 255 as defined in CCITT G.712
Terminating Impedance: 900W + 2.16µF
Transmit Gain/Loss:0 to -9 dB, switch selectable per channel
Receive Gain/Loss: 0 to -9 dB, switch selectable per channel
Modem Support: Full compatibility with V.34 and V.90 modems. Patented automatic analog impedance adjustment adapts to various modems and line lengths
Transmit TLP Maximum: +6dBm
Receive TLP Maximum: +3dBm
Longitudinal Balance
- Loop-Start: 200Hz to 1000Hz > 81dB, 1000Hz to 4000Hz > 70dB
- Ground-Start: 200Hz to 1000Hz > 73dB, 1000Hz to 4000Hz > 61dB

FXO Signaling Performance

DC Loop Range: 4000W DC signaling
Ringer Equivalency Number (REN): 0.4B (AC)
Ringing Voltage Detection: Detects Class A and B ringing, follows distinctive ringing
Maximum DC: 150 mA
Control Technique: Solid-state, no mechanical relays.
Overvoltage: 600Vrms without fire hazard per UL 1459, 2nd ed., FCC part 68 lightning protection
Protection: Solid-state (fuse-less) overvoltage and overcurrent protection
Termination Type: FXO loop-start or FXO ground-start, switch selectable per channel
Signaling Selection: DPT functionality enabled/disabled on all 12 channels
Address Signaling: DTMF or dial pulse
Calling Party Disconnect: Calling party disconnect detects and forwards current interruption to disconnect answering device and modems

Compliance

FCC Part 68, CS-03 listed for connection to PSTN
FCC Part 15, Class A Radiated Emissions Control
NRTL safety listed: UL 1459, CSA
National Electrical Code 1996 safety requirements

Environmental

Operational Temperature: 0° - 50° C (32° to 122° F)
Relative Humidity: 0 - 95%