Nevion EDFA-B-C 17dBm User Manual

EDFA-B-C 17dBm

SDI optimized Erbium Doped Fiber Amplifier

User manual

Rev. B

Nevion

Nordre Kullerød 1
3241 Sandefjord
Norway
Tel: [phone]

nevion.com

EDFA-B-C 17dBm Rev. B

Nevion Europe

P.O. Box 1020

3204 Sandefjord, Norway
Support phone 1: [phone]
Support phone 2: [phone]

Nevion USA

1600 Emerson Avenue

Oxnard, CA 93033, USA

Toll free North America: [phone]

Outside North America: [phone]

E-mail: [e-mail]

See http://www.nevion.com/support/ for service hours for customer support globally.

Rev.

Repl.

Date

Sign

Change description

B 0 2014-05-21

OEH

Added LED chapter

0 A 2012-01-11

SHH

Initial revision.

A - 2008-02-01

Initial revision (not published)

Nevion Support

Revision history

Current revision of this document is the uppermost in the table below.

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EDFA-B-C 17dBm Rev. B

Contents

Revision history ........................................................................................................ 2

1 Product overview ................................................................................................... 4

2 Specifications ........................................................................................................ 5

2.1 Optical Characteristics .................................................................................................. 5

2.2 Power consumption ....................................................................................................... 5

2.3 Environmental conditions ................................................................ .............................. 5

3 Cautions ................................................................................................................ 6

3.1 Laser Safety ................................................................................................ .................. 6

4 Configuration ......................................................................................................... 7

4.1 Dip switch settings ........................................................................................................ 7

4.1.1 Common dip switches ................................................................................................ 7

4.1.2 Constant power mode ................................................................................................ 7

4.1.3 Constant gain mode ................................................................................................... 7

4.2 Status by LED’s ............................................................................................................. 8

4.2.1 LED status description ............................................................................................... 8

4.3 GPI ................................................................................................................................ 9

4.4 RS232 control ..............................................................................................................10

4.5 Lid operated switches...................................................................................................11

4.6 Key switch ....................................................................................................................11

5 Connections ........................................................................................................ 12

6 Operation ............................................................................................................. 13

6.1 Introduction ..................................................................................................................13

6.2 EDFA theory ................................................................................................................13

6.3 Operation modes ..........................................................................................................13

General environmental requirements for Nevion equipment .................................. 15

Product Warranty.................................................................................................... 16

Appendix A Materials declaration and recycling information .................................. 17

A.1 Materials declaration ....................................................................................................17

A.2 Recycling information ...................................................................................................17

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EDFA-B-C 17dBm Rev. B

1 Product overview

The Flashlink EDFA-B-C 17dBm is an erbium doped fiber amplifier with a special control
circuit making it better for SDI signals than normal EDFAs. It is a +17dBm booster that is
typically used at the beginning or in the middle of a link. At the receiving end of a link, a low
power / low noise preamp would typically be needed instead.

The EDFA is unidirectional by nature, but can amplify up to 40 DWDM channels on a single
fiber, at 100GHz spacing. Ideal gain flatness is achieved with input power close to the
nominal input power.

Various safety measures are implemented, like automatic shutdown if rear lid is opened to
access the fiber connectors, or manual shutdown by the use of GPI, GYDA, RS422 or

turning the safety key to the “off” position. There is also a reduced output power mode that

can be entered with the use of GPI, GYDA or RS422 control.
EDFA can also be directly controlled over RS232, bypassing the Flashlink features. The

key, lid, GPI and GYDA/RS422 still operate the shutdown and reduced output power
modes, even when using direct RS232 control.

EDFA status is monitored by use of LEDs, GPIO and RS422/GYDA.

Figure 1: EDFA block diagram

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EDFA-B-C 17dBm Rev. B

Nominal input power

-6dBm

Maximum input power

+4dBm

Minimum input power

-10dBm

Total output power

17dBm +/- 1.5dBm at Pin from -10dBm to 0dBm

Gain flatness

Max. 1.0dB at Pin=-6dBm, Pout=17dBm
Max. 5.0dB at Pin from -10dBm to 0dBm

Noise figure

Max. 6.0dB at Pin=-6dBm, Pout=17dBm

Wavelength range

Full C-band, 1529 to 1562nm

Number of DWDM ch.

Min. 40 channels at 100GHz spacing

Polarization dependant gain

Max. 0.5dB

Polarization Mode
Dispersion

Max. 0.5ps

Input/Output return loss
(pump off)

Min. 35dB

Maximum power
consumption:

<9W (+5V)

Operation temperature
range

0°C – 45°C

Operation without damage
temperature range

0°C – 55°C

2 Specifications

2.1 Optical Characteristics

2.2 Power consumption

2.3 Environmental conditions

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EDFA-B-C 17dBm Rev. B

3 Cautions

3.1 Laser Safety

This unit is capable of emitting dangerous levels of light.
DO NOT UNDER ANY CIRCUMSTANCES LOOK AT THE OUTPUT OF THE

UNIT OR FIBRE ATTACHED TO THE UNIT!
Containing a Class IIIb assembly, use the utmost case when changing

connections, and always turn the unit completely off before inspecting or
cleaning any connectors which are attached to the unit’s output.

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EDFA-B-C 17dBm Rev. B

Pos

Name

Function ON

Function OFF

Comment

1

G_P

Constant Gain

Constant Power

Fundamental working mode for
EDFA.

7

A_M

Autonomous
and/or
GYDA/DIP
control

Manual RS232
control

Set OFF to use the RS232 port in the
front of the EDFA to control
parameters like function (constant
power, gain or drive),

8

OVR

Dip switches
active

GYDA active

When ON, only dip switches can
change configuration. GYDA can only
monitor. To control with GYDA, set to
OFF.

Pos

Name

Function ON

Function OFF

Comment

2

S_T

SDI optimised

Telco optimised

Chooses between signal types
present on the fiber. For a low number
of SDI signals which might display
pathological signals (shifts in average
power), set dip ON. For many
channels with fast adaptation to
varying input levels, set dip OFF.

3

G3

Add 14dBm

Add 10dBm

These dip switches set the output
power, from a minimum of +10dBm to
a maximum of +17.5dBm (0.5dB
step).

4

G3

Add 2dBm

Add 0dBm

5

G2

Add 1dBm

Add 0dBm

6

G1

Add 0.5dBm

Add 0dBm

Pos

Name

Function ON

Function OFF

Comment

2

S_T

Not used

Not used

No effect in Constant Gain mode.

3

G3

Add 18dB

Add 10dB

These dip switches set the gain, from
a minimum of 10dB to a maximum of
25dB (1dB step).

4

G2

Add 4dB

Add 0dB

5

G1

Add 2dB

Add 0dB

6

G0

Add 1dB

Add 0dB

4 Configuration

4.1 Dip switch settings

The dip switches are also documented on the front of the EDFA
The following dip switches change the meaning of the other dip switches:

4.1.1 Common dip switches

4.1.2 Constant power mode

In this mode, dip switch 1, 7 and 8 is set ON.

4.1.3 Constant gain mode

In this mode, dip switch 1 is set OFF, while switches 7 and 8 are set ON.

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EDFA-B-C 17dBm Rev. B

Diode \ state

Red LED

Yellow LED

Green LED

No light

Status

Module is faulty

Module is OK
Module has power

Module has
no power

TEMP

Laser
temperature
alarm

Ambient
temperature alarm

Temperature is OK

LOS & LOP

Loss of input
signal

Loss out output
signal
(mute/bypass)

Signal is OK
LASER

Laser fail

Laser disabled
(mute/bypass)

Laser is OK.

Status

TEMP

LOS & LOP

LASER

4.2 Status by LED’s

The status of the module can be easily monitored visually by the LEDs at the front of the
module. The LEDs are visible through the front panel as shown below.

Figure 2: Panel indicator overview (Text not printed on the front panel)

4.2.1 LED status description

The functions of the different LEDs are described in table below.

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EDFA-B-C 17dBm Rev. B

Signal

Name

Pin #

Mode

Direction

STATUS

Pin 1

Open Collector

Output

LOS

Loss of input signal/power

Pin 2

Open Collector

Output

LOP

Loss of output
signal/power

Pin 3

Open Collector

Output
TERM

Temperature out of range

Pin 4

Open Collector

Output

LASER

Laser bias current out of
range

Pin 5

Open Collector

Output

DIS

DISABLE (completely shut
off bias current to the
laser).

Pin 6

TTL, 0V =
active level

Input
MUTE

MUTE (output power goes
below class 1 limits).

Pin 7

TTL, 0V =
active level

Input
Ground

0 volt pin

Pin 8

0V.

4.3 GPI

These outputs can be used for wiring up alarms for third party control systems. The GPI
outputs are open collector outputs, sinking to ground when an alarm is triggered. The GPI
connector is shown in figure 7.

There are two GPI inputs, one for muting output power (power goes to below safe limit) and
one for complete disable (same function as key switch, lid and software disable command).

Electrical Maximums for GPI outputs

Max current: 100mA
Max voltage: 30V

EDFA-B-C 17dBm module GPI pinning:

Figure 3: GPI Outlet

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EDFA-B-C 17dBm Rev. B

Command

Example response

Comment

GET_STATUS

MODULE:DISABLED DI
CONTROL: AGC
ALARMS: NORMAL
LD: NORMAL

GET_INFO

GET_BAUD

Bit rate of serial port.

SET_BAUD [4800,9600,
14400,19200,38400]

OK
GET_ECHO

SET_ECHO [ON,OFF]

OK

Echoes characters back to the
terminal. Off by default

GET_MODE

MODE: G 18.80 dB

SET_MODE [P,G,C,M]<value>

OK

Power in dBm, Gain in dB, Current in
mA or M***MISSING***

GET_LD_POW

Laser diode power measurement

GET_MPD [1,2,ALL]

MPD1: -1.82 dBm, 6.58E-01 mW
MPD2: -8.29 dBm, 1.48E-01 mW

1: input, 2: output
GET_LD_CRNT

Laser diode bias current measurement

GET_ALARM_LD_CRNT

Alarm limit for laser diode bias current

SET_ALARM_LD_CRNT
<value,D>

GET_LD_TEC

Laser diode thermal stabiliser current

GET_TPUMP

TPUMP: 25.47 C

GET_ALARM_TPUMP_HI

ALARM_TPUMP_HI: 30.00 C

SET_ALARM_TPUMP_HI
<value,D>

OK
GET_ALARM_TPUMP_LO

ALARM_TPUMP_LO: 20.00 C

SET_ALARM_TPUMP_LO
<value,D>

OK
GET_TCASE

TCASE: 31.03 C

Ambient temperature

GET_ALARM_TCASE_HI

ALARM_ TCASE_HI: 70.00 C

Upper alarm limit

SET_ALARM_TCASE_HI
<value,D>

OK
GET_ALARM_TCASE_LO

ALARM_ TCASE_LO: 0.00 C

SET_ALARM_TCASE_LO
<value,D>

OK
GET_LOS_SWD

SET_LOS_SWD [ON,OFF,CP]

GET_LOS

Threshold for loss of signal. Input
power below this triggers muting of
output power.

SET_LOS <value>

HELP

…

The complete list of commands

4.4 RS232 control

If dip switch 7 (“A_M”) is set OFF (Manual), the GYDA/dip switch control over the EDFA will
halt and the RS232 input will be enabled (RS232 output is always on). Bitrate 9600, 8N1 (8
databits, no parity, 1 stop bit). A typical prompt will be “MSA::EDFA>”. When the prompt
returns, the module is ready for a new command. There is an option to set the bitrate of the
EDFA module to something else than 9600, but this will disable autonomous/GYDA
operation until reset back to 9600.

The following table lists the most useful commands (the HELP command will list all
commands):

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EDFA-B-C 17dBm Rev. B

4.5 Lid operated switches

If the lid covering the fiber connectors on the backplane should be opened, the EDFA will
automatically disable. This is done both by a switch in direct contact with the lid, and by
software through the use of an optical sensor.

4.6 Key switch

The key switch in the front of EDFA-B-C 17dBm can be used to disable the EDFA. The key
can only be removed when the switch is in the OFF position.

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EDFA-B-C 17dBm Rev. B

5 Connections

The backplane module EDFA-C1 has 3 connectors (GPI, RX and TX) and a lid covering the
optical ports.

To connect or disconnect fiber patch cords to the optical ports, the lid must be opened. This
is done by unscrewing the thumb screw and lifting the lid up. Even though opening the lid
automatically disables the EDFA, we recommend always disabling the EDFA by turning the
key before opening the lid.

The RX port is on the right, TX on the left.
The third port (to the left of the thumb screw) is the GPI port, with pinout as described in

chapter 4.3.

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EDFA-B-C 17dBm Rev. B

1
2

6 Operation

6.1 Introduction

The EDFA-B-C 17dBm will typically be used as a midway booster when there are many
signals on the fiber, or directly after the transmitter / DWDM multiplexer if there are few
signals. The reason for this is that optimum input power on the EDFA for DWDM
applications is -6dBm.

A full 40-channel system based on the flashlink DWDM-40C together with 0dBm flashlink
transmitters will already have approximately +14dBm1 at the output, thereby requiring a
20dB attenuator to get +17dBm (just 3dB up) with a flat gain response out of the EDFA-B-C
17dBm.

On the other hand, a narrow band DWDM system (up to 8 channels) will not experience
problems with the gain/frequency response of the EDFA-B-C 17dBm, and can therefore
directly benefit from the +17dBm output power (compared to the app. +7dBm1 from 8
channels in a DWDM-8C).

6.2 EDFA theory

Understanding the way the erbium doped fiber amplifier works can lead to easier handling
of problems that occur, such as wideband noise, signal dependent noise (bit errors under
certain signal conditions) etc.

The pump laser at 1480nm (980nm would be used for a low-noise preamp with low output
power) and a short piece of fiber with a small amount of SiO2 (glass) molecules in the
structure replaced by Er2O3 are the central elements of an EDFA. The photons at 1480nm
emitted from the laser excite electrons belonging to the erbium atoms. The excited state
(called 11/2, actually a broad range of sub states and thermic variations in energy) has a
limited life span, but if a photon at the appropriate wavelength (energy) comes close to this
electron, it will collapse down to the ground state (15/2) with a new photon emitted at the
excact same phase and direction as the original photon. If no photon passes by within the
life span of the excited state, the electron will collapse by itself, and a photon will be
generated at the wavelength matching the energy level, in a random direction. Some of
these photons will have a direction along the signal path of the fiber, and will therefore be
amplified by other excited electrons at the same energy level. This is called amplified
spontaneous emission (ASE) and is the primary source of noise introduced in an EDFA.

6.3 Operation modes

An EDFA can normally be operated in one of three modes: AGC, ACC or APC. The EDFA­B-C 17dBm has dip switch and GYDA settings for two of these, AGC (referred to in this

document as “Constant Gain”) and APC (“Constant Power”).

In “Constant Power” mode, the output power is regulated independently of input power. In

“Constant Gain” mode, the output power varies with input power.

In addition, there are two different versions of “Constant Power”. For use with a relatively

low number of SDI links which might transport a pathological signal2, there is a special SDI
mode. When using this mode, the EDFA should not be used near saturation (full output

power). Recommended output power in “SDI optimised Constant Power” mode is +14dBm.

There are two reasons for this. First, the regulation loop is slower in this mode, therefore
adding or subtracting optical channels from the fiber can lead to bit errors in other channels

Example values, not for performance indications.
Specifically the EQ stressing 19-1 sequence that comes from displaying a uniform purple colour over several whole video

lines.

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EDFA-B-C 17dBm Rev. B

if the overhead is insufficient. Second, an EDFA driven to saturation will not handle long
streams of either 0 or 1.

When the number of channels running on the fiber is high and the signals are uncorrelated,

the recommended operating mode is “Telco optimised Constant Power”. In this mode, the

EDFA will have a very fast regulation loop that ensures error free operation on other
channels when one or more channels are added/subtracted from the fiber. For this mode,
operation in saturation (full output power) is recommended.

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EDFA-B-C 17dBm Rev. B

1.

The equipment will meet the guaranteed performance specification under the following
environmental conditions:

-

Operating room temperature range:

0°C to 40°C

-

Operating relative humidity range:

up to 90% (non-condensing)

2.

The equipment will operate without damage under the following environmental
conditions:

-

Temperature range:

0°C to 50°C

-

Relative humidity range:

up to 90% (non-condensing)

General environmental requirements for Nevion equipment

nevion.com | 15

EDFA-B-C 17dBm Rev. B

Product Warranty

The warranty terms and conditions for the product(s) covered by this manual follow the
General Sales Conditions by Nevion, which are available on the company web site:

www.nevion.com

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EDFA-B-C 17dBm Rev. B

組成名稱

Part Name

Toxic or hazardous substances and elements

鉛

Lead

(Pb)

汞

Mercury

(Hg)

镉

Cadmium

(Cd)

六价铬

Hexavalent

Chromium

(Cr(VI))

多溴联苯

Polybrominated

biphenyls

(PBB)

多溴二苯醚

Polybrominated

diphenyl ethers

(PBDE)

EDFA-B-C 17dBm

O O O O O

O

O: Indicates that this toxic or hazardous substance contained in all of the homogeneous materials for this part is
below the limit requirement in SJ/T11363-2006.

X: Indicates that this toxic or hazardous substance contained in at least one of the homogeneous materials used
for this part is above the limit requirement in SJ/T11363-2006.

Appendix A Materials declaration and recycling
information

A.1 Materials declaration

For product sold into China after 1st March 2007, we comply with the “Administrative
Measure on the Control of Pollution by Electronic Information Products”. In the first stage of

this legislation, content of six hazardous materials has to be declared. The table below
shows the required information.

This is indicated by the product marking:

A.2 Recycling information

Nevion provides assistance to customers and recyclers through our web site

http://www.nevion.com/. Please contact Nevion’s Customer Support for assistance with

recycling if this site does not show the information you require.
Where it is not possible to return the product to Nevion or its agents for recycling, the

following general information may be of assistance:

 Before attempting disassembly, ensure the product is completely disconnected from

power and signal connections.

 All major parts are marked or labeled to show their material content.
 Depending on the date of manufacture, this product may contain lead in solder.
 Some circuit boards may contain battery-backed memory devices.

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