PLC 1790

ALSPA PLC 1790B Ed1&2

March 2004

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POWER LINE CARRIER ALSPA PLC 1790B

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POWER LINE CARRIER ALSPA PLC 1790B Ed2

PLC

179

0/C

2 14 20 26 32 4036 45 55 65 76

LED 1 GREEN LED 2 GREEN

LED 4 REDLED 3 GREEN

LED 6 YELLOWLED 5 GREEN

LFS

LED 1 GREEN

LED 2 RED

ALIM

M8 J4

RX

INRX

5 dB

PLC-1

RX

TX

PLC-2

OVF LF0

OVF LF1

OVF A/DRX

TX

RX

RX -5dB

RX +5dB

LFSQUELCH

DSP OK

LOOP

DSP KO

MODAF

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SUMMARY

1. Generalities

2. Characteristics

3. General block diagram

4. LFS

5. CCUN

6. INTE

7. INSU

8. ELNU

9. INAF

10. MODAF

11. AMPL

12. INTX

13. INRX

14. DC/DC Converter

15. Configuration

16. User cables interface

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ACRONYM. MEANING

LFS Low frequency section

CCUN Universal ringing converter

INTE AF transit interface

INSU Network management interface

ELNU Digital signal processing unit

AMPL Amplifier

INAF HF interface

INTX HF transmission filter

INRX Line interface and reception filter

ALIM DC / DC converter

MODAF Audio Frequency Modem

DSP Digital signal processor

CODEC A / D & D / A converter serial type

TPS Selective tele protection

FSK Frequency shift keying

00K On / off keying

1. GENERALITIES

Acronym's List

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1. GENERALITIES

General description

The Alspa PLC 1790B equipment bases its function on the use of DSP(Digital signal processor), either for the AF and HF signals elaboration while the inputs/outputs are still analog.

Frequencies transposition is based on SSB modulation principle with attenuated and calibrated carrier transmitted on line.

The use of DSP improves the performance of the equipment in terms of quality, service and flexibility, reducing meantime thecost and the maintenance operations as well as the hardware volume.

The operator, using a standard personal computer, can easily customize the equipment and performs tests either on-line or off-line from one end of the link.

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1. GENERALITIES

AF Services

Speech and signaling/dialing

Data

Selective teleprotection

HF Medium

Over head power line

Under ground power cable

Facilities

Permanent link control

Integrated party line service on AF side

Possibility of high speed data transmission

Fully programmable

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2. CHARACTERISTICS

Useful bands

HF : 40 to 500 Khz

AF : 300 to 3720 Hz

1 or 2 multipurpose and/or full band transit(simply add one AF board for a 2 channels configuration)

HF frequency arrangement

Programmable by step of 1 Khz using PC

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2. CHARACTERISTICS

Line filters (Tx and Rx)

Customization by hardware for all single or double channels starting 40 Khz up to 500 Khz.

Nominal transmission output

10 / 20 / 40 Watts on HF output (the output can be reduced up to 20 dB lower than the nominal level trough software adjustment).

Power amplifier

Push-Pull type polarized in AB class : nominal output power 20 watts

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2. CHARACTERISTICS

Line hybrid

4 wires : impedance 75 ΩΩΩΩ unbalanced

2 wires : impedance - 75 ΩΩΩΩ unbalanced- 50 / 125 / 150 ΩΩΩΩ balanced or

unbalanced

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3. GENERAL BLOCK DIAGRAM Ed1

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3. GENERAL BLOCK DIAGRAM Ed2

HF Line

LFS-0 (*) MODAF AMPL-1 INTX

INRX

AMPL-2

LF Section HF Section

INTE-0 (*)

#

#

#

#Digital Signal

Analogue Signal

Alternative Units

LFS-1 (*)

#

CH-0

CH-1

INSU (*)PC

RS232

(*) = SERVICE Units

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4. LFSBlock diagram

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4. LFS

Function

Programmable multipurpose Low Frequency board

- manages the following service :

- speech signaling telegraph full band transit

- internal FSK modem analog general purpose TPS interface

Speech

Programmable bandwidth :

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4. LFS

Speech field interface

Programmable for 2 wires or 4 wires by software and hardware

600 ΩΩΩΩ impedance

Levels : adjustable by software at 0,5 dB step

- 4 wires Tx (dBm) Rx (dBm)

- Range +1,5 to -22,5 +7,5 to -23,5

- Default -3.5 -3.5

- 2 wires

- Range +5 to -19 +4 to -34

- Default 0 -7

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4. LFS

Compandor

According to CCITT G162 recommendation

Excludable by software or by external command

Speech limiter

According to IEC 495 specification

Excludable by software

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4. LFS

Signaling

programmable via software as FSK (FC + 30 Hz) type

Transmission and reception idle frequency can be independently changed

Programmable FC

- Transmission criteria : Ground on "M" wire

- Reception criteria : Ground on "E" wireFree voltage contact (SC2)

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4. LFS

Telegraph service

Programmable bandwidth

Line impedance 600 ΩΩΩΩ

Tx / Rx levels adjustable by software from +5 to -33 dBm at 0,5 dB step(-14 dBm for 50 bauds as default value)

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B AU D R A T E C H A N N E L B A N D W IT C H H Z S T A N D AR D50 120 U IT .T R -35 + P ro p rie ta ry

100 240 U IT .T R -37 + P ro p rie ta ry200 360 U IT .T R -38B + P ro p rie tary200 480 U IT .T R -38A600 30 0 à 27 00 U IT .T V -23600 10 80 P ro p rie tary

120 0 30 0 à 34 00 U IT .T V -23

4. LFS Internal programmable modem : MTU

Programmable for IUT.T standard, baud rate from 50 to 1200 bauds

FSK modulation and output level variable following the baud rate (the level can be fixed at 50 bauds)

Only asynchronous transmission mode

Transmission and reception are programmable independently on two different channels (DTR & RTS forcing by switches)

Field interface RS232 / V-24 type

Tx & Rx LED's on LFS board connected respectively to RTS and CR signals

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4. LFS

AF transit "Line 2" access

Programmable for 2 different functions:

- Selective or full band transit

- Analog teleprotection interface

• Warning : whenever selective AF transit is programmed the telegraph service is automatically set at 300 to 3720 Hz bandwidth

Line impedance 600 ΩΩΩΩ

On the receive input from field, a corrector is available to compensate the eventual cable level distortion. 15 presettedcurves are selected by software configuration.

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4. LFS

AF Transit "Line 2" levels

For teleprotection function :

- Tx/Rx : adjustable from +3 to -35 dBm

For transit function :

- Speech Tx/Rx +3 to -35 dBm at 0,5 dB step nominal -18 dBm

- Data Tx/RX -7 to -45 dBm at 0,5 dB step nominal -28 dBm for 50 bauds

- Signaling Tx/Rx -7 to -45 dBm at 0,5 dB step nominal -28 dBm

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4. LFS

LF equalizer

Available on the receive line from HF section

The operator can test automatically the HF line response and equalize eventually the receiver, adjusting eight different filters

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5. CCUN

Function :

Call and receive signal converter (E and M) for a two wires telephonic connection.

Double circuits unit (only one board for two channels)

Applications (programmable by soldering straps).

PLA-C long line extension exchange side

PLA-T long line extension telephone side

BC central battery (hot line)

BL local battery

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5. CCUN

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5. CCUN

Characteristics

Ringing current frequency 45 + 5 Hz

Ringing voltage 50 à 80 VRMS on 3 K ΩΩΩΩ

Subscriber voltage 30 VDC

Microphone current 25 à 35 mA

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6. INTE

Function :

AF full band transit interface.

Double circuits unit (only one board for two channels)

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6. INTE

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7. INSU

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7. INSU

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8. ELNUDSP / CODEC DIGITAL LINKS

»TDM=Time-division Multiplexing

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8. ELNU

ELNU digital signal elaboration

The following functions are performed:

Synchronism generation and carrier digital synthesis of HF channels.

These functions are supported by:

• Main oscillator, which generates the master clock

• Centralized logic to provide for the machine timings

• Generation of HF mo-demodulation carriers.

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8. ELNUELNU : Tx operation principle

• Synchronism and exchange of data coming from channels 1 and 2

• Modulation of channels 1 and 2

• Sum of the two communication channels and carrier

• Transmission level adjustment

• Sampling frequency increase from 32 to 2048 kHz

• HF band allocation

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8. ELNUELNU : Rx operation principle

• Demodulation of digital signal received from INAF board

• Reduction of the sampling frequency from 1024 to 16 kHz

• Demodulation and carrier drop for automatic level control (AGC)

• Channel 1 and channel 2 demodulation:

• Synchronism and exchange of serial data to be sent to channel 1 (LFS 0)

• Synchronism and exchange of serial data to be sent to channel 2 (LFS 1 fordouble channel PLC terminals).

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8. ELNU

HF Line alarms (M8)

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9. INAF

BLOCK DIAGRAM

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10. MODAF

BLOCK DIAGRAM

DSP 56302Motorola

FLASHMemory

FLASHMemory

EEPromMemory

TRASMISSION [ 1 ]

TO AMPL.1

TO AMPL. 2

D / A

TXtest point

RECEPTION

A / D

D / A

FROM RXFILTER

AGCCONTROL

AGCRX

test point

BUS

I/O 16 bit

ALARMSCRITERIA

TXRX+5 dB / -5dBPLC / PLC1

POWER SUPPLY

I/O 16 bit

LFS-0

LFS-1

INSU

SSI LINK

PC LINK

FPGAXilinx Spartan

IIE

WD

TPS OUT

P/S

7 dB

TPS 12-16 kHz Output

D / A7 dB

P/S

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11. AMPL

BLOCK DIAGRAM ( 20 Watts power amplifier )

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12. INTX

BLOCK DIAGRAM

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13. INRX

BLOCK DIAGRAM

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14. DC/DC CONVERTER

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(* Optionnal)

UNIT QUANTITY POS.

10 WATTS 20 WATTS 40 WATTS SUBRACK

ALIM. DC/DC 1 1 1 A

INSU* 1 1 1 E

ELNU 1 1 1 F

INAF 1 1 1 G

AMPL 1 H

AMPL 1 1 1 I

INTX 1 1 1 L

INRX 1 1 1 M

15. CONFIGURATION Rev1

Equipment configuration

Basic configuration

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(* Optionnal)

UNIT QUANTITY POS.

10 WATTS 20 WATTS 40 WATTS SUBRACK

ALIM. DC/DC 1 1 1 A

INSU* 1 1 1 E

Empty F

MODAF 1 1 1 G

AMPL 1 H

AMPL 1 1 1 I

INTX 1 1 1 L

INRX 1 1 1 M

15. CONFIGURATION Rev2

Equipment configuration

Basic configuration

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APPLICATION CONFIGURATION LFS0 LFS1 CCUN INTE

1 Multipurpose channel 1 LFS D

1 Multipurpose channel with 2 wires speech interface 1 LFS + CCUN D C

1 Full band transit channel 1 INTE D

2 Multipurpose channels with 2 wires speech interface 2 LFS + CCUN D B C

2 Full band transit channels 1 INTE D

1 Multipurpose channel + 1 Full band transit channel 1 LFS + INTE D B

1 Multipurpose channel with 2 wires speechinterface + 1 Full band transit channel

1 LFS + CCUN + INTE D C B

15. CONFIGURATION

LF Configurations

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16. USER CABLES INTERFACE Ed1

Field connectors arrangement (front view)

All the field connectors are located in front of the equipment

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16. USER CABLES INTERFACE Ed2

Field connectors arrangement (front view)

All the field connectors are located in front of the equipment

PowerSupply

M3 LF1Sp/Sig/L2

M2 LF0Sp/Sig/L2

M5 LF1MTU

M4 LF0MTU

M37O.C. ALARMS

M38ALARMS

M9TPS

M7INSU R.C.

M6P.C.

J4TESTPOINT

J1HF LINE

M38 J5COAX. CABLE

J2PLC HF

LINE

J3PLC DUMMY

LOAD

M10 LF0TELEGRAPH

3 x I/O

M32 LF1TELEGRAPH

3 x I/O

M40 LF0TELEGRAPH

1 x I/O

M41 LF0TELEGRAPH

1 x I/O

M13-M14

M15-M16

M17-M18

RA

CK

ALA

RM

S

(-) A (+) BPowerSupplyGround

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16. USER CABLES INTERFACE

Field connectors arrangement (front view)

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