Fractional E1(Nx64kbps) G.703/G.704 - X.21 Interface Converter: DC3000

Metrodata Limited

The DC3000 provides a new level of price and performance in connecting switches and routers to an unstructured or structured E1 G.703/G.704 2.048Mbps leased line.

The DC3000 provides the conversion necessary to connect the X.21 serial interface of a router to a 2Mbps leased line.

Fractional E1 (Nx64kbps) G.703/G.704 to X.21 Converter

dc3000-x21-simple.png
DC3000 as an E1 G.703/G.704 to Nx64kbps X.21 converter
  • Cost Effective E1 G.703/G.704 2.048Mbps interface conversion
  • X.21 DCE port for router connection
  • Fractional Nx64kbps support
  • E1 2Mbps G.703 port for leased line connection
  • Easy to install & maintain
  • Integral auto-sensing power supply (100-250V AC or -48V DC versions)
  • 12-24V DC power supply available on request
  • External alarm relay port
  • Compact modem style unit, built to European standards
  • Rack mounting kits for 2 or 18 units available
  • Quad option available with 4 DC3000 units in a 1U box
  • Can also be used in reverse connecting an E1 device such as a router to an X.21 service
  • Can also be used to connect E1 devices to EIA530 satellite modems

Router Applications

  1. X.21 router to E1 2Mbps G.703 leased line conversion
  2. Connecting pairs of X.21 routers over an E1 2Mbps G.703 leased line
  3. E1 G.704 router to Nx64kbps X.21 leased line conversion
  4. Connecting pairs of E1 G.704 routers over a Nx64kbps X.21 leased line

PBX Applications

  1. PBX PRI to X.21 2Mbps leased line conversion
  2. Connecting pairs of PBXs over a 2Mbps X.21 leased line

Satellite Applications

  1. Connecting E1 G.703 routers to EIA530 satellite modems

DC3000 connecting an X.21 router to an unframed or framed E1 G.703/G.704 leased line

dc3000-router-x21-e1g704-cloud.png

This application shows a DC3000 connecting an X.21 router card to an E1 G.703 2.048Mbps leased line, such as a BT Megastream-2 service. X.21 serial ports are often the most cost effective WAN port available on routers. Most Telecom carriers provision E1 2.048Mbps services with G.703 connectivity. Care must be taken to ensure that the remote equipment is configured in a compatible manner (i.e. both ends unframed or both ends framed). If the leased line is framed then the equipment at both ends of the leased line must also be framed.

X.21 routers connected together via an unframed or framed E1 G.703 leased line using DC3000 units

dc3000-router-x21-e1g704-cloud-x21-router.png

This application shows a pair of DC3000 units connecting a pair of X.21 routers via an E1 G.703 2.048Mbps leased line, such as a BT Megastream-2 service. X.21 serial ports are often the most cost effective WAN port available on routers. Most Telecom carriers provision E1 2.048Mbps services with G.703 connectivity. Care must be taken to ensure that the remote equipment is configured in a compatible manner (i.e. both ends unframed or both ends framed). If the leased line is framed then the equipment at both ends of the leased line must also be framed.

DC3000 connecting an E1 G.704 router to an X.21 Nx64kbps leased line

dc3000-router-e1g704-x21-cloud.png

This application shows a DC3000 connecting an E1 G.704 router card to an X.21 Nx64kbps leased line, such as a BT Kilostream-N service. Care must be taken to ensure that the remote equipment is configured in a compatible manner (i.e. either X.21 or E1 G.704 framed). This application requires an X.21 DCE to X.21 DCE crossover cable. Please note that this application will NOT work where E1 timeslot integrity is required (e.g. when using channelised E1 cards in the routers).

E1 routers connected together over an X.21 Nx64kbps leased line using DC3000 units

dc3000-router-e1g704-x21-cloud-e1g704-router.png

This application shows a pair of DC3000 units connecting a pair of E1 G.704 routers via an X.21 Nx64kbps leased line, such as a BT Kilostream-N service. Care must be taken to ensure that the remote equipment is configured in a compatible manner (i.e. either X.21 or E1 G.704 framed). This application requires the use of X.21 DCE to X.21 DCE crossover cables. Please note that this application will NOT work where E1 timeslot integrity is required (e.g. when using channelised E1 cards in the routers).

DC3000 connecting a PBX to a 2.048Mbps X.21 leased line

dc3000-pbx-e1g704-x21-cloud.png

This applications show a DC3000 being used to connect a PBX PRI port to a 2.048Mbps X.21 leased line, for when either an existing X.21 leased line is available for re-use or alternatively when X.21 connectivity has been provided rather than G.703 (e.g. for economic reasons). This application requires an X.21 DCE to X.21 DCE crossover cable. Please note that this application will NOT work over an Nx64kbps service, e.g. a BT Kilostream-N.

PBXs connected together via a 2.048Mbps X.21 leased line using DC3000 units

dc3000-pbx-e1g704-x21-cloud-e1g704-pbx.png

This applications shows how a pair of PBX systems can be connected together via a 2.048Mbps leased line using a pair of DC3000 units. This would occur either when an exisiting X.21 leased line is available for re-use, or alternatively when an X.21 connectivity has been provided rather than G.703 (e.g. for economic reasons). This application requires the use of X.21 DCE to X.21 DCE crossover cables. Please note that this application will NOT work over an Nx64kbps service, e.g. a BT Kilostream-N.

Connecting E1 routers to EIA530 satellite modems

dc3000-router-e1g704-eia530-satmodem.png

This application shows a DC3000 connecting an E1 G.704 router card to an EIA530 satellite modem. The DC3000 supports a number of different clocking modes, and so it is possible to source the clocking for this network from the satellite modems, from one of the terrestrial circuits or from a DC3000 or router. This application requires an X.21 DCE to EIA530 DCE crossover cable. Please note that this application will NOT work where E1 timeslot integrity is required (e.g. when using channelised E1 cards in the routers, or when using a PBX).


The DC3000 offers conversion between an X.21 serial interface and an E1 line interface with BNC or RJ45 connector options. The DC3000 supports both unframed and framed (or fractional) operation.

Fractional operation allows a number of 64kbps timeslots to be active, up to a maximum of 31 timeslots for a single E1 line. If timeslot 16 is bypassed, then a maximum of 30 timeslots (channels) can be accommodated.

The DC3000 has a simple multi-function status LED and BIT switch configuration with comprehensive configuration and diagnostic information on the unit base label making the DC3000 a truly plug and play device.

It is possible to connect the DC3000 to EIA-530 or RS-449 equipment using a converter cable.

The DC3000 range can easily be rackmounted in either a 1U two unit rackmount kit, a 6U eighteen unit rackmount kit or also available in quad box option (4 x DC3000 units).


E1 Line Interface

Port G.703, 75 ohm unbalanced, 120 ohm balanced
Interface
BNC (75 ohm), RJ45 (120 ohm)
Framing
G.704 (with or without CRC4) or unframed
Line Coding
HDB3
Bit Rate 2.048Mbps +/- 50 ppm
Barrier Fully compliant as per EN41003
Cable Lengths BNC: RG59 = 600m, UR202 = 750m

RJ45: Belden 8132 = 175m, Belden 9841 = 300m

DTE Interface

Port
X.21
Interface
15 way female D type
Bit Rate
2.048 Mbps or Nx64kbps (N = 1 to 31)

Configuration

Clocks
Internal, E1 Loop, Terminal, DTE Mode, set by dip switches
Set Up
Start Timeslot: 1 to 31

Bandwidth: 1 to 31

CRC4: Enable / Disable

Timeslot 16 bypass: Enable / Disable

Status Display

Type
Status LED on rear panel
Off
Mains power off
Red
Loss of Signal (LOS)
Green
Unit OK

Compliance & Approvals

Performance PD7024 (NTR4)
Safety
EN41003, EN60950
EMC
EN55022, EN50082

Environment

Temp
0 - 50 deg C
Humidity
95% RH, non-condensing
Pressure
86 - 106kPa

Power Supply

AC Mains
100 - 250VAC, 50 - 60Hzm 35 - 15mA, IEC Connector
-48VDC Supply
-40 to -72 VDC, 100 - 50mA
Power Consumption
3.5 watts approx when operating

Packaging

Type
Modem, 1U high without feet, IP30C

Dimensions ( W x D x H mm )

Rackmount
202 x 132 x 44 (without feet)
Desktop
202 x 132 x 48 (with feet)


Order Code

Product

AC Mains: 100 - 250 VAC
DC Power: -48 VDC
DC3000
80-05-230
80-21-230
2 Unit Rackmount Kit
80-05-256 80-05-256
18 Unit Rackmount Kit
80-05-250 80-05-255
Quad DC3000
80-405-230
80-421-230

Product variants with 12V to 24V DC operation are also available on request.


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