FXS 12-Channel Voice Card

Quick Resources: PDF Brochures

Operational Description

The Foreign Exchange Station (FXS) 12-channel voice card delivers high quality loop or ground-start dial tone telephone line connections to key systems, off-premises extensions, facsimile machines, modems, PBXs and other conventional analog telephone devices. This card supports calling party disconnect (CPD) and most CLASS® features including caller ID and distinctive ringing.

The FXS card receives T1 signaling, tip and ring pairs, control logic and power through a 64-pin connector inside the Access Bank or Access Exchange unit. The back plate of the FXS card provides 12 multi-color LEDs for monitoring call progress and channel status. The back plate also contains 3 DIP switches for selecting E&M signaling options, a busy/idle card switch, and 12 test switches that can also be used to "busy out" individual channels. On the FXS card itself, each channel has 6 DIP switches for setting transmit and receive line attenuations.

When equipped with the FXS voice card, the Access Bank and Access Exchange can support a number of popular signaling types used by dedicated T1-accessed voice service providers, including:

AT&T Megacom ®
NYNEX Flexpath®
US West DSS®
Long-distance Automatic Number Identification (ANI) and Dialed Number Identification Service (DNIS) from long distance carriers.

The FXS circuits automatically perform impedance matching to adapt to various PBXs, key systems, telephones, modems and line lengths.

Physical Description

The FXS card 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.

FXS Card Features and Advantages

Features

Advantages

E&M support is configured per card, using DIP switches

E&M immediate start to loop-start or ground start

E&M wink start to loop-start or ground-start

E&M wink delay (ANI/DNIS) to loop-start or ground-start

Allows common signaling conversion

FXS Support

Allows:

Automatic loop-start or ground-start selection on every channel

Most CLASS® features including caller ID and distinctive ringing

Fuseless overvoltage and overcurrent safety protection

Prevents card overcurrent damage

Full compatibility with V.34 & V.90 modems

Versatility in working with common modem type

Carrier Access patented automatic impedance balancing

Card adapts to line conditions

Technical Specifications

FXS 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: +3.0 dBm/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: +12dBm with FXS gain set to -9dB
Receive TLP Maximum: +3dBm with FXS gain set to 0dB
Idle Noise: A/D <15 dBrnCO, D/A, 10dBrnCO
Longitudinal Balance:> 63dB in FXS off-hook state measured per IEEE 455 and FCC Part 68
Impulse Noise: 0 counts above 47dBrnCO

FXS Signaling Performance

DC Loop Range: 1200W (3 miles on 24 AWG + 300W telephone), Exceeds EIA/TIA-464A and Bellcore TR-57
Loop Feed: Nominal -48VDC with 30mA current limit
Ringing Voltage: All-channel simultaneous ringing power, 85Vrms, 20Hz, thermal current limited, provided by LUI
Maximum Ringers: 5 REN, FCC Class B ringers
Ring Trip Time: >50ms, <150ms with 1500W termination
Control Technique: Solid-state, no mechanical relays.
Overvoltage: 600Vrms without fire hazard per UL 1459, 2nd ed., FCC part 68 lightning protection, solid-state (fuse-less) overvoltage and overcurrent protection
Off-Hook Detection: Detects tip or ring currents > 8mA, rejects for <4mA
Tip Ground: <200W with 30mA current limit
Ring Ground: Detects ring ground currents >8mA
Internal Ringing Cadence: Ringing cadence is 2 seconds on, 4 seconds off for E&M wink start conversion modes
CLASS® Support: Supports CLASS features such as calling party ID, three-way calling, and distinctive ringing
Calling Party Disconnect: Calling party (forward) disconnect provides 2 second current interruption to disconnect answering devices and modems - requires E&M signaling service such as Megacom on the T1
FXS Signaling: FXS loop-start or FXS ground-start with automatic LS/GS selection per channel
FXSDN Signaling: E&M immediate or wink start to either loop-start or ground-start conversion with ringback tone for carrier services such as Megacom®, Flexpath®, DSS®, VPN®, VNET®, etc. Wink delay for advanced ANI/DNIS 800 number services and Direct Inward-Dial (DID) conversion
PLARD: Private Line Automatic Ringdown (PLARD) - E&M immediate start signaling with ringback tone to network
Ringer Equivalency Number (REN): 0.0 by definition
Trunk Processing Option: One switch per FXS card selects busy (tip lead grounded) or idle (tip lead open)

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%