EXFO FVA-3150 User Manual

FVA-3150

Variable Attenuator

User Guide

Copyright © 2010–2011 EXFO Inc. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form, be it electronically, mechanically, or by any other means such as photocopying, recording or otherwise, without the prior written permission of EXFO Inc. (EXFO).

Information provided by EXFO is believed to be accurate and reliable. However, no responsibility is assumed by EXFO for its use nor for any infringements of patents or other rights of third parties that may result from its use. No license is granted by implication or otherwise under any patent rights of EXFO.

EXFO’s Commerce And Government Entities (CAGE) code under the North Atlantic Treaty Organization (NATO) is 0L8C3.

The information contained in this publication is subject to change without notice.

Trademarks

EXFO’s trademarks have been identified as such. However, the presence or absence of such identification does not affect the legal status of any trademark.

Units of Measurement

Units of measurement in this publication conform to SI standards and practices.

Version number: 1.0.0

ii FVA-3150

Contents

Certification Information ........................................................................................................v

1 Introducing the FVA-3150 Variable Attenuator .......................................... 1

Main Features .........................................................................................................................1

Front Panel .............................................................................................................................2

Back Panel ..............................................................................................................................3

Available Models ....................................................................................................................4

Typical Applications ................................................................................................................4

Main Concept .........................................................................................................................5

Conventions ............................................................................................................................6

2 Safety Information ....................................................................................... 7

Laser Safety Information .........................................................................................................7

Electrical Safety Information ...................................................................................................8

3 Getting Started With Your Variable Attenuator ....................................... 11

Installing your FVA-3150 Variable Attenuator in a Rackmount .............................................11

Turning the Variable Attenuator On and Off .........................................................................13

Accessing Menus ..................................................................................................................14

4 Setting Up Your Variable Attenuator ........................................................ 15

Selecting the Display Intensity ..............................................................................................15

Locking Control Key Access ...................................................................................................16

Managing the Wavelength Shortlist .....................................................................................17

Selecting the Attenuation .....................................................................................................20

Selecting and Using an Attenuation Display Mode ...............................................................24

Saving and Recalling a Configuration ...................................................................................31

5 Operating Your Variable Attenuator ......................................................... 35

Cleaning and Connecting Optical Fibers ...............................................................................35

Installing the EXFO Universal Interface (EUI) .........................................................................37

Performing an Attenuation Routine ......................................................................................38

Operating the Shutter ...........................................................................................................44

Variable Attenuator iii

Contents

6 Controlling Your Variable Attenuator Remotely .......................................45

Setting Up the Variable Attenuator for Remote Control .......................................................45

Communication Parameters ..................................................................................................48

Standard Status Data Structure ............................................................................................49

Command Structure .............................................................................................................51

Error Messages .....................................................................................................................52

SCPI Management Errors (System Errors) ..............................................................................53

RS-232 Connector Pinout ......................................................................................................54

7 Maintenance ................................................................................................55

Cleaning EUI Connectors ......................................................................................................56

Cleaning Detector Ports ........................................................................................................58

Recalibrating the Unit ...........................................................................................................59

Recycling and Disposal (Applies to European Union Only) ....................................................60

8 Troubleshooting ..........................................................................................61

Contacting the Technical Support Group ..............................................................................61

Transportation ......................................................................................................................62

9 Warranty ......................................................................................................63

General Information .............................................................................................................63

Liability .................................................................................................................................64

Exclusions .............................................................................................................................65

Certification ..........................................................................................................................65

Service and Repairs ...............................................................................................................66

EXFO Service Centers Worldwide ..........................................................................................67

A Technical Specifications ..............................................................................69

B Remote Control Commands .......................................................................71

IEEE 488.2 Required Commands ...........................................................................................71

Specific commands-Quick Reference Command Tree ............................................................79

Index ...............................................................................................................103

iv FVA-3150

Certification Information

FCC Information

Electronic test equipment is exempt from Part 15 compliance (FCC) in the United States. However, compliance verification tests are systematically performed on most EXFO equipment.

 Information

Electronic test equipment is subject to the EMC Directive in the European Union. The EN61326 standard prescribes both emission and immunity requirements for laboratory, measurement, and control equipment. This unit has undergone extensive testing according to the European Union Directive and Standards.

CSA Information

This unit is certified by the CSA (certificate number 162451) and was evaluated according to applicable CSA and UL standards (as confirmed by “C-US” mark) as well as applicable IEC standards for use in Canada, the United States, and other countries.

Variable Attenuator v

Certification Information

Application of Council Directives: 2006/95/EC - The Low Voltage Directive 2004/108/EC - The EMC Directive 2006/66/EC - The Battery Directive

93/68/EEC - CE Marking And their amendments Manufacturer’s Name: EXFO Inc. Manufacturer’s Address: 400 Godin Avenue Quebec, Quebec Canada, G1M 2K2 Equipment Type/Environment: Test & Measurement / Industrial

Trade Name/Model No.: Variable Attenuator / FVA-3150

Standard(s) to which Conformity is Declared:

EN 61010-1:2001 Edition 2.0 Safety Requirements for Electrical Equipment for Measurement,

Control, and Laboratory Use – Part 1: General Requirements.

EN 61326-1:2006 Electrical Equipment for Measurement, Control and Laboratory

Use - EMC Requirements

EN 55022: 2006 + A1: 2007 Information technology equipment — Radio disturbance

characteristics — Limits and methods of measurement

I, the undersigned, hereby declare that the equipment specified above conforms to the above Directives and Standards.

Manufacturer

Signature:

Full Name: Stephen Bull, E. Eng

Position: Vice-President Research and

Development

Address: 400 Godin Avenue, Quebec (Quebec),

Canada, G1M 2K2

Date: June 2, 2010

DECLARATION OF CONFORMITY

vi FVA-3150

1 Introducing the FVA-3150

Variable Attenuator

Main Features

The FVA-3150 Variable Attenuator is the instrument that allows you to perform several attenuation related tasks.

The FVA-3150 Variable Attenuator is configured for singlemode and multimode fibers. It is built to offer a high spectral uniformity, an important feature which allows you to maintain the attenuation value throughout the entire WDM spectrum. Its low insertion loss allows you to minimize your loss budget.

The FVA-3150 Variable Attenuator has a program function, which allows you to create custom programs such as automatic attenuation scan.

The Variable Attenuator has the versatility of three display modes:

 Absolute, which includes the insertion loss.

 Reference, in reference to the 0.001 dB level.

 Offset, relative display to any selected reference value.

The FVA-3150 Variable Attenuator is controlled by easy-to-use software, enabling multiple-user configuration storage.

The FVA-3150 Variable Attenuator can be remotely controlled through a GPIB or RS-232 interface.

Variable Attenuator 1

Introducing the FVA-3150 Variable Attenuator

VARIABLE ATTENUATOR

FVA-3150

Offset

ENTER

Abs Up Shutter

Ref



Down Attenuation

Program

Setup

Output port

Offset mode access

Reference mode access

Confirmation button (Enter)

Absolute mode access

Wavelength control

Arrow buttons for menu navigation and parameter setting

Program menu access

Monitor port (BM and DM models only)

On/off button

Display

Shutter control

Attenuation controls

Step

In Monitor Out

Input port

Setup menu access

Shutter

Front Panel

Note: Your FVA-3150 Variable Attenuator may differ slightly from the illustration

depending on the specific model of your unit.

2 FVA-3150

Back Panel

Electro-Optical Engineering

465 Godin Avenue Vanier QC G1M 3G7 Canada

GPIB IEEE 488.2

SH1, AH1, T6, L4, SR1, RL1, PP0, DC1, DT1, C0, E2

This device complies with part 15 of th e FCC rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference and (2) this devic e must accept any interference received, including interference that may cause undesired operation.

Made in Canada

P/N

S/N

Ver.

Mfg. date

QST-151F

Serial Port

MODEL: GO LR107723

100-240 V 50/60 Hz 2 A F2AL250 V

Serial port (RS-232 DTE)

Fuse holder

Power inlet

GPIB port

Ver.

Mfg. date

S/N

FVA-3150-B-EI

12345-AB

A-1.0

ANUARY

2010

9/125 µ

1200 TO 1650

P/N

Ground

Version number

Spectral range

Manufacturing date

Part number

Fiber type

Serial number

Introducing the FVA-3150 Variable Attenuator

Back Panel

Note: Your FVA-3150 Variable Attenuator may differ slightly from the illustration

depending on the specific model of your unit.

Variable Attenuator 3

Introducing the FVA-3150 Variable Attenuator

Available Models

According to the models you own, additional options are available. The FVA-3150-CM, FVA-3150-BM, and FVA-3150-DM all come with a monitor output, which ensures accurate power-level monitoring.

Typical Applications

The FVA-3150 Variable Attenuator is ideal for:

 manufacturing and laboratory applications such as system

characterization

 EDFA

 component and system loss simulation

 instrument calibration

 power meter linearity measurement

 spectral tuning

The FVA-3150 Variable Attenuator is particularly suitable to demanding laboratory and manufacturing qualification applications.

4 FVA-3150

Introducing the FVA-3150 Variable Attenuator

Main Concept

The significance of the attenuation value displayed by an optical attenuator may differ from one manufacturer to another. At EXFO, for example, the attenuation displayed by the FVA-3150 Variable Attenuator is the actual loss or attenuation between the input and the output ports of the Variable Attenuator, including the loss of its own internal connectors, after performing a reference reading with a power meter.

IMPORTANT

The Variable Attenuator has been calibrated with a light source connected to the input port and a power meter connected to the output port. For optimum performance, do not interchange the input and output connections.

Variable Attenuator 5

Introducing the FVA-3150 Variable Attenuator

Conventions

Before using the product described in this manual, you should understand the following conventions:

WARNING

Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury. Do not proceed unless you understand and meet the required conditions.

CAUTION

Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury. Do not proceed unless you understand and meet the required conditions.

CAUTION

Indicates a potentially hazardous situation which, if not avoided, may result in component damage. Do not proceed unless you understand and meet the required conditions.

IMPORTANT

Refers to information about this product you should not overlook.

6 FVA-3150

2 Safety Information

Laser Safety Information

WARNING

Do not install or terminate fibers while a light source is active. Never look directly into a live fiber and ensure that your eyes are protected at all times.

WARNING

Use of controls, adjustments and procedures for operation and maintenance other than those specified herein may result in hazardous radiation exposure or impair the protection provided by this unit.

Variable Attenuator 7

Safety Information

Electrical Safety Information

This unit uses an international safety standard three-wire power cable. This cable serves as a ground when connected to an appropriate AC power outlet.

Note: If you need to ensure that the unit is completely powered off, disconnect the

power cable.

WARNING

 Insert the power cable plug into a power outlet with a

protective ground contact. Do not use an extension cord without a protective conductor.

 Before powering on the unit, connect all grounding terminals,

extension cords and devices to a protective ground via a ground socket. Any interruption of the protective grounding is a potential shock hazard and may cause personal injury. Whenever the ground protection is impaired, do not use the unit and secure it against any accidental operation.

 Do not tamper with the protective ground terminal.

The color coding used in the electric cable depends on the cable. New plugs should meet the local safety requirements and include:

 adequate load-carrying capacity

 ground connection

 cable clamp

IMPORTANT

EXFO assumes no liability if you attempt to perform internal service on this unit.

8 FVA-3150

Safety Information

Electrical Safety Information

WARNING

 Use this unit indoors only.

 Position the unit so that the air can circulate freely around it.

 Operation of any electrical instrument around flammable gases

or fumes constitutes a major safety hazard.

 Do not remove unit covers during operation.

 To avoid electrical shock, do not operate the unit if any part of

the outer surface (covers, panels, etc.) is damaged.

 Only authorized personnel should carry out adjustments,

maintenance or repair of opened units under voltage. A person qualified in first aid must also be present. Do not replace any components while power cable are connected.

 Use only fuses with the required rated current and specified

type (IEC, 5 mm x 20 mm (0.197 in x 0.787 in), fast-blow, 250 V, 2 A). Do not use repaired fuses or short-circuited fuse holders.

 Capacitors inside the unit may be charged even if the unit has

been disconnected from its electrical supply.

Variable Attenuator 9

Safety Information

Electrical Safety Information

Equipment Ratings

Tem pe rat ur e

 Operation

 Storage

Relative humidity

0 °C to 40 °C (32 °F to 104 °F)

-40 °C to 70 °C (-40 °F to 158 °F)

0 % to 80 % non-condensing

Maximum operation altitude 2000 m (6562 ft)

Pollution degree 2

Overvoltage category II

Power supply rating

100 V to 240 V (50 Hz/60 Hz)

maximum input power 2 A

a. Measured in 0 °C to 31 °C (32 °F to 87.8 °F) range, decreasing linearly to 50 % at 40 °C (104 °F).

b. Not exceeding

± 10 % of the nominal voltage.

The following label is located on the back panel of the unit:

10 FVA-3150

3 Getting Started With Your

Variable Attenuator

Installing your FVA-3150 Variable Attenuator in a Rackmount

You can place your FVA-3150 Variable Attenuator in a rackmount to facilitate its usage.

To install the rackmount:

1. Fix the angle iron using four flat Phillips screws.

2. Fix the rackmount bracket to the frame using two round Phillips

screws.

3. Fix the rackmount stiffener using two flat Phillips screws (for the front panel) and two round Phillips screws.

4. If your rackmount will contain only one unit, fix the rackmount cover plate to the empty part of the frame using four flat Phillips screws.

Variable Attenuator 11

Getting Started With Your Variable Attenuator

Installing your FVA-3150 Variable Attenuator in a Rackmount

To install your FVA-3150 Variable Attenuator in a rackmount:

1. Slide the benchtop unit into the rackmount and tighten it from

underneath using the four cover fixing screws.

If measurement X on the illustration exceeds 11.125 in., fix the unit into the four holes identified as A. Otherwise, use the other four holes.

2. If a second benchtop is to be installed, remove the cover plate and repeat step 1.

12 FVA-3150

Getting Started With Your Variable Attenuator

Turning the Variable Attenuator On and Off

When you turn on your unit:

 it beeps twice

 it performs a self-test

 it enters the mode that was active at the last power-off (Absolute,

Offset, or Reference)

When you turn the unit off, the following items remain in read-only memory:

 current shutter state

 current display mode

 current attenuation setting

 current wavelength

 shortlisted wavelengths

 each wavelength offsets

 step size

 remote-control settings

 programmed attenuation routine settings

 saved configurations

Note: The power cord is the most effective disconnecting device. To ensure that

the power is completely turned off, disconnect the power cord.

Variable Attenuator 13

Getting Started With Your Variable Attenuator

Program

Setup

Delay Duration

Step

ATT.

Start

Stop

Exit

Step Lambda

Offset

Dimmer GPIB-RS

Save

Recall Exit

Lockout

Accessing Menus

To turn the unit on and off:

Use the red button in the lower left corner of the front panel.

IMPORTANT

Some internal mechanisms can sometimes take a few seconds to adjust, depending on the operation performed. While the Variable Attenuator is performing internal adjustments (for example after having changed the wavelength or the attenuation setting), no buttons should be pressed while Program flashes on the display.

CAUTION

The Variable Attenuator should not be turned off while Program is flashing in the lower left corner of the display.

Accessing Menus

The blue buttons to the right of the display give access to single-level menus: Program and Setup. The following diagram shows the menus and their items.

To move (in a loop) between the menu items:

Use the left/right arrows.

To exit a menu:

Press the button that gave access to the menu;

Use the left/right arrows to move until EXIT is displayed, then press ENTER.

14 FVA-3150

4 Setting Up Your Variable

Attenuator

Selecting the Display Intensity

Display intensity may be set to high or low. You can also turn off the display without turning off the unit.

To select the display intensity:

1. Press the Setup button.

2. Use the left/right arrows to move until it displays DIMMER.

3. Press ENTER. The current dimmer state will start flashing.

4. Use the up/down arrows to modify the dimmer status: LO, HI, or OFF.

5. Press ENTER.

Note: Setting the dimmer to OFF turns off the display. Press any button to turn the

display back on.

6. To exit the Setup menu, press the Setup button.

Variable Attenuator 15

Setting Up Your Variable Attenuator

Locking Control Key Access

To prevent unintended use of the FVA-3150 Variable Attenuator during operation, you can lock the control keys (the blue buttons on the front panel of the unit).

To lock the control key access:

1. Press the Setup button.

2. Use the left/right arrows until LOCKOUT is displayed.

3. Press ENTER.

The LOCKED message is briefly displayed, then the unit reverts to the settings that were active before you entered the Setup menu. All control keys are deactivated.

To unlock the keypad:

1. Press the Setup button.

2. Press ENTER.

The UNLOCKED message is briefly displayed. All control keys are reactivated.

16 FVA-3150

Setting Up Your Variable Attenuator

Managing the Wavelength Shortlist

The FVA-3150 Variable Attenuator can test at many wavelengths. The accepted wavelengths depend on the configuration of your unit. You can store the wavelengths you use most often in a shortlist so you can quickly access them. The shortlist includes up to 20 wavelengths.

Note: When switching to a new wavelength, the attenuator motor will reposition

itself to keep the current attenuation value for the new wavelength.

Refer to Technical Specifications on page 69 for more information on the wavelength ranges that you can enter.

Variable Attenuator 17

Setting Up Your Variable Attenuator

Managing the Wavelength Shortlist

To add a wavelength to the shortlist:

1. Press the Setup button.

2. Use the left/right arrows to move until LAMBDA is displayed.

3. Use the up/down arrows to move until Add is displayed .

4. Press ENTER. A wavelength will be suggested and the first digit will

flash.

5. Use the up/down arrows to change the flashing digit and the left/right arrows to activate the next digit.

6. Once all digits are set, press ENTER.

7. To exit the Setup menu, press the Setup button.

Note: If you are trying to enter a wavelength that is outside the wavelength range,

the Variable Attenuator will beep and reject the wavelength.

18 FVA-3150

Setting Up Your Variable Attenuator

Managing the Wavelength Shortlist

To delete a wavelength from the shortlist:

1. Press the Setup button.

2. Press the left/right arrows until LAMBDA is displayed.

3. Use up/down arrows to move until the wavelength you want to delete

appears in the lower portion of the display.

4. Press ENTER. The wavelength will start flashing.

5. Set all the wavelength digits to zero. To do so, use the up/down arrows

to change the flashing digit and the left/right arrows to activate the next digit.

6. Press ENTER.

7. To exit the Setup menu, press the Setup button.

To delete all wavelengths from the shortlist:

1. Press the Setup button.

2. Press the left/right arrows until LAMBDA is displayed.

3. Press the up/down arrows until DEL ALL appears in the lower portion

of the display.

4. Press ENTER.

Variable Attenuator 19

Setting Up Your Variable Attenuator

Selecting the Attenuation

The attenuation can be set using two methods:

 By using the up and down arrows buttons, the attenuation is modified

one step (up or down) at a time.

 By using the Attenuation button, you can quickly and precisely set the

attenuation to a specific value

The available step sizes are: 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, and 50 dB.

Note: Selecting a larger step size allows for faster attenuation scanning.

To change the step size:

1. Press the Setup button.

2. Press the left/right arrows until STEP is displayed.

3. Press ENTER. The current step size will start flashing.

4. Using the up/down arrows, select one of the available step sizes.

5. Press ENTER.

6. To exit the Setup menu, press the Setup button.

20 FVA-3150

Setting Up Your Variable Attenuator

Abs

Attenuation setting

Current wavelength

Selecting the Attenuation

To enter a specific attenuation value:

1. Press the Attenuation button. The first segment of the attenuation

setting starts flashing.

2. Enter a new attenuation value. Use the up/down arrows to change the flashing digit and the left/right arrows to activate the next digit.

Note: The difference with the current attenuation must be of at least 0.002 dB for

the new attenuation setting to be valid. For more information on the variable attenuator optical resolution see Technical Specifications on page 69.

3. Once you have entered all the segments, press ENTER.

Note: If you try to set an attenuation value that is outside the attenuation range,

the Variable Attenuator will default to the minimum or maximum setting.

The attenuation range (minimum and maximum possible attenuation) of your FVA-3150 Variable Attenuator depends on the model you have at hand. Although EXFO guarantees that the minimum insertion loss is below a specified value, it may vary slightly from one wavelength to another and from one variable attenuator to another.

Variable Attenuator 21

Setting Up Your Variable Attenuator

VARIABLE ATTENUATOR

FVA-3150

Offset

ENTER

Abs Up Shutter

Ref



Down Attenuation

Program

Setup

Absolute mode access

Step

In Monitor Out

Shutter

Wavelength control Attenuation

Selecting the Attenuation

To set the minimum attenuation:

1. Select a wavelength, by pressing  until you reach the desired

wavelength.

2. Press the Abs button.

3. Press the Attenuation button and set an attenuation of 00.000 dB.

4. Press ENTER. The Variable Attenuator will default to the minimum

insertion loss.

22 FVA-3150

Setting Up Your Variable Attenuator

Selecting the Attenuation

To set the maximum attenuation:

1. Select a wavelength by pressing  until you reach the desired

wavelength.

2. Press the Abs button.

3. Press the Attenuation button and set an attenuation of -99.999 dB.

4. Press ENTER. The Variable Attenuator will default to the maximum

attenuation.

Variable Attenuator 23

Setting Up Your Variable Attenuator

Selecting and Using an Attenuation Display Mode

Note: The total or absolute attenuation referred to in this manual is the actual

optical insertion loss between the input and output ports, including the connectors.

The Variable Attenuator offers the following three attenuation display modes:

 Absolute attenuation mode

 Offset attenuation mode

 Reference attenuation mode

Display Mode Description

Absolute The displayed attenuation value takes into account both

the absolute value and the offset value.

Default mode upon initial activation.

Reference (relative)

24 FVA-3150

The displayed attenuation value is the attenuation relative to a defined reference value, which can be any value within the unit’s attenuation range and may be selected as the reference.

Setting Up Your Variable Attenuator

Selecting and Using an Attenuation Display Mode

Display Mode Description

Offset (X + B) The displayed attenuation is the sum of two components:

 X = physical attenuation introduced by the unit.

 B = correction factor or offset; it may be used to

compensate for losses along the connecting fibers or for losses displaying the attenuation as a power value.

Offset mode can be best explained by the following example:

 An optical light source with a power output of -14 dBm

at 1310 nm is connected to a variable attenuator. Because of internal losses, the minimum insertion loss at 1310 nm is approximately 2 dB. This means that the maximum optical power available at the output port of the attenuator is -16 dBm (-14 + -2). If we now set an offset value of -14 dBm, the (large digits) will display the optical power level at the output port of the attenuator. Using the above setup (that is, light source, variable attenuator, and an accurately determined offset value), EXFO has created a precise variable light source with a dynamic range of nearly 100 dB.

Note: You must define the appropriate B value for

the operating wavelength before enabling X+B mode. A different B value may be assigned to each wavelength in the wavelength box.

Note: The active display mode is always indicated on the display.

Variable Attenuator 25

Setting Up Your Variable Attenuator

Abs

Absolute attenuation

Wavelength

Selecting and Using an Attenuation Display Mode

To set Absolute attenuation mode:

Press the Abs button at any time to enable Absolute mode.

In Offset mode, the offset value is always displayed in the lower portion of the display while the upper portion (large digits) displays the sum of two values.

Before enabling the Offset mode, it is necessary to define the appropriate offset value for the operating wavelength. A different offset value can be associated with each wavelength in the shortlist.

26 FVA-3150

Setting Up Your Variable Attenuator

dBm

Current offset value for the selected wavelength

Selecting and Using an Attenuation Display Mode

To define an offset value for a specific wavelength:

1. Set the Variable Attenuator to the appropriate wavelength.

2. Select Setup.

3. Press the left/right arrows until OFFSET is displayed.

4. Press ENTER. The first segment of the current offset value will start

flashing.

5. Enter a new offset. Use the up/down arrows to change the flashing digit and the left/right arrows to activate the next digit.

Note: Offset values between -99.999 and 99.999 may be entered. Use dB when

the offset represents loss and dBm when the offset represents power.

6. Once all the segments have been entered, press ENTER.

7. To exit the Setup menu, press the Setup button.

Variable Attenuator 27

Setting Up Your Variable Attenuator

Offset

Offset attenuation (actual attenuation is -6.00 dB)

Offset value for the current wavelength

Selecting and Using an Attenuation Display Mode

To use the offset mode:

1. Ensure that the display is in Absolute mode (select Abs).

2. Select the appropriate wavelength by pressing  until you reach the

desired wavelength.

3. If necessary, set an offset value.

4. Select Offset. The display will switch to Offset mode.

Note: The offset value can be modified while Offset mode is active.

28 FVA-3150

Setting Up Your Variable Attenuator

Ref

Relative attenuation

Absolute attenuation

Selecting and Using an Attenuation Display Mode

Any value within the attenuation range may be selected as the reference. When Reference mode is enabled (by selecting Ref):

 the current absolute attenuation setting becomes the reference value

and appears in the lower portion of the display; and

 0.000 dB (relative attenuation) is displayed in the upper portion of the

display.

If the attenuation is increased by 1.0 dB, the upper digits (relative attenuation) will display -1.000 dB and the lower digits (absolute attenuation) will indicate -17.450 dB.

Variable Attenuator 29

Setting Up Your Variable Attenuator

VARIABLE ATTENUATOR

FVA-3150

Offset

ENTER

Abs Up Shutter

Ref



Down Attenuation

Program

Setup

Reference mode access

Absolute mode access

Step

In Monitor Out

Shutter

Selecting and Using an Attenuation Display Mode

To use the Reference mode:

1. Ensure that the display is in Absolute mode (select Abs).

2. Select the appropriate wavelength.

3. Set the attenuation to the desired reference value.

4. Press the Ref. button.The display will switch to Reference mode.

Note: Pressing Ref with the Reference mode already active will reset the

reference value to the current absolute attenuation setting.

30 FVA-3150

Setting Up Your Variable Attenuator

Saving and Recalling a Configuration

Once the Variable Attenuator has been customized for a specific application or user, it is possible to save the configuration. Saved parameters are:

 current wavelength and attenuation

 display mode

 step size

 shortlisted wavelengths

 each wavelength offset

 programmed attenuation routine settings

Up to ten configurations can be saved and recalled.

Variable Attenuator 31

Setting Up Your Variable Attenuator

Configuration number

Saving and Recalling a Configuration

To save a configuration:

1. Customize the Variable Attenuator as required.

2. Press the Setup button.

3. Press the left/right arrows until SAVE is displayed.

4. Press ENTER. The configuration number will start flashing.

5. Press the up/down arrows to modify the configuration number.

6. Press ENTER.

7. Press the Setup button to exit the menu.

Once you have saved a configuration (see Saving and Recalling a Configuration on page 31), you can recall it at any time.

32 FVA-3150

Setting Up Your Variable Attenuator

Configuration number

Saving and Recalling a Configuration

To recall a configuration:

1. Press the Setup button.

2. Press the left/right arrows until RECALL is displayed.

3. Press ENTER. The configuration number (bottom of the screen) will

start flashing.

4. Use the up/down arrows to select the number of the configuration you want to recall.

5. Press ENTER.

6. To ex it th e Set up menu, press the Setup button.

Variable Attenuator 33

5 Operating Your Variable

Attenuator

Cleaning and Connecting Optical Fibers

IMPORTANT

To ensure maximum power and to avoid erroneous readings:

 Always inspect fiber ends and make sure that they are clean as

explained below before inserting them into the port. EXFO is not responsible for damage or errors caused by bad fiber cleaning or handling.

 Ensure that your patchcord has appropriate connectors. Joining

mismatched connectors will damage the ferrules.

To connect the fiber-optic cable to the port:

1. Inspect the fiber using a fiber inspection microscope. If the fiber is

clean, proceed to connecting it to the port. If the fiber is dirty, clean it as explained below.

2. Clean the fiber ends as follows:

2a. Gently wipe the fiber end with a lint-free swab dipped in isopropyl

alcohol.

2b. Use compressed air to dry completely.

2c. Visually inspect the fiber end to ensure its cleanliness.

Variable Attenuator 35

Operating Your Variable Attenuator

Cleaning and Connecting Optical Fibers

3. Carefully align the connector and port to prevent the fiber end from touching the outside of the port or rubbing against other surfaces.

If your connector features a key, ensure that it is fully fitted into the port’s corresponding notch.

4. Push the connector in so that the fiber-optic cable is firmly in place, thus ensuring adequate contact.

If your connector features a screwsleeve, tighten the connector enough to firmly maintain the fiber in place. Do not overtighten, as this will damage the fiber and the port.

Note: If your fiber-optic cable is not properly aligned and/or connected, you will

notice heavy loss and reflection.

36 FVA-3150

Operating Your Variable Attenuator

Bare metal

(or blue border)

indicates UPC

option

Green border

indicates APC

option

2 3 4

Installing the EXFO Universal Interface (EUI)

The EUI fixed baseplate is available for connectors with angled (APC) or non-angled (UPC) polishing. A green border around the baseplate indicates that it is for APC-type connectors.

To install an EUI connector adapter onto the EUI baseplate:

1. Hold the EUI connector adapter so the dust cap opens downwards.

2. Close the dust cap in order to hold the connector adapter more firmly.

3. Insert the connector adapter into the baseplate.

4. While pushing firmly, turn the connector adapter clockwise on the

baseplate to lock it in place.

Variable Attenuator 37

Operating Your Variable Attenuator

Performing an Attenuation Routine

You can program the FVA-3150 Variable Attenuator to perform an attenuation routine. Once the routine is started, the variable attenuator will automatically increase or decrease the inserted attenuation (by steps), return to the initial attenuation state, and perform the routine again until you stop it. The following parameters may be set:

 delay: the beginning of the attenuation routine may be delayed by up to

999 hours, 59 minutes and 59 seconds

 duration: the variable attenuator can remain up to 999 hours,

59 minutes and 59 seconds at each attenuation step

 number of steps: the attenuation routine may comprise up to 99 steps

 attenuation difference between two steps: the difference in

attenuation between two steps may be up to 99.999 dB

Note: Once set, the routine parameters remain in memory until new ones are

entered.

The following example shows how parameters are set up, as well as how an attenuation routine works.

If you start an attenuation routine with the following settings:

 Delay: 5 minutes

 Duration: 10 seconds

 Number of steps: 3

 Attenuation difference between each step: –1 dB, and

 Initial attenuation state: –10 dB

the Variable Attenuator will:

 Wait five minutes before starting the routine

 Remain at –10 dB attenuation for 10 seconds (step 0)

38 FVA-3150

Operating Your Variable Attenuator

Hours

Seconds

Minutes

Performing an Attenuation Routine

 Switch to –11 dB attenuation for 10 seconds (step 1)

 Switch to –12 dB attenuation for 10 seconds (step 2)

 Switch to –13 dB attenuation for 10 seconds (step 3), and

 Return to the initial attenuation state (-10 dB) for 10 seconds (step 0)

and repeat the routine until you stop it

To program the attenuation routine:

1. Press the Program button.

2. Press ENTER. The first digit will start flashing. Use the up/down arrows

to change the flashing digit and the left/right arrows to activate the next digit.

Variable Attenuator 39

Operating Your Variable Attenuator

Hours

Minutes

Seconds

Performing an Attenuation Routine

3. If you do not want the routine to be delayed, leave the delay at 000.00.00.

4. Once the delay is set, press ENTER.

5. Select the duration (time for which the Variable Attenuator will remain

at each step). Press the right arrow.

6. Press ENTER. The first digit will start flashing. Use the up/down arrows to change the flashing digit and the left/right arrows to activate the next digit.

7. Once the duration is set, press ENTER.

8. Press the right arrow. You will see the following display.

40 FVA-3150

Operating Your Variable Attenuator

Performing an Attenuation Routine

9. Press ENTER. The first digit will start flashing. Use the up/down arrows to change the flashing digit and the left/right arrows to activate the next digit.

10. Once the number of steps is set, press ENTER.

11. Press the right arrow. To set the attenuation difference between the

steps.

12. Press ENTER. The first segment will start flashing. Use the up/down arrows to change the flashing digit and the left/right arrows to activate the next digit.

Note: Entering a negative value will increase the attenuation (in absolute value)

during the routine. Entering a positive value will decrease it.

13. Once the step size is set, press ENTER.

Note: The difference with the current attenuation must be of at least 0.002 dB for

the new attenuation step size to be valid.

14. Press the Program button to exit the menu.

Note: The initial attenuation state counts as a step.

Variable Attenuator 41

Operating Your Variable Attenuator

VARIABLE ATTENUATOR

FVA-3150

Offset

ENTER

Abs Up Shutter

Ref



Down Attenuation

Program

Setup

Program menu access

Step

In Monitor Out

Shutter

Wavelength control

Performing an Attenuation Routine

To start a routine:

1. Set the wavelength by pressing  until you reach the desired

wavelength.

2. Set the Variable Attenuator to the initial attenuation.

3. Press Program.

4. Press left/right ar rows until START is displayed.

5. Press ENTER. Program, in the lower left portion of the display,

indicates that an attenuation routine is in progress.

Note: During a program, if the attenuation reaches the limit of the attenuation

range, it will remain set at this value until the routine is completed.

Once you have started the routine, the display goes back to the current attenuation mode display.

42 FVA-3150

Operating Your Variable Attenuator

Performing an Attenuation Routine

To know... perform the following steps

how much time is left in the delay

how much time is left in the current step

how many steps are left in the current routine

To stop the attenuation routine:

1. Press Program.

2. Press the left/right arrows until STOP is displayed.

3. Press ENTER.

The routine completes the current attenuation step, then stops (Program disappears from the display).

Press Program

Press the left/right arrows until DELAY is displayed.

Press Program

Press the left/rigth arrows until DURATION is displayed.

Press Program

Press the left/rigth arrows until STEP is displayed.

Variable Attenuator 43

Operating Your Variable Attenuator

VARIABLE ATTENUATOR

FVA-3150

Offset

ENTER

Abs Up Shutter

Ref



Down Attenuation

Program

Setup

Shutter control

Step

In Monitor Out

Shutter

Operating the Shutter

The optical shutter is an electro-mechanical device which, when activated, totally blocks light transmission.

To block light transmission:

Use the Shutter button to turn the shutter on or off. When the shutter is activated, Shutter On appears in the lower right portion of the display.

CAUTION

Using the shutter continuously at a rate of one cycle per three seconds may damage the instrument permanently or seriously reduce its life cycle.

44 FVA-3150

6 Controlling Your Variable

GPIB setting

Attenuator Remotely

The FVA-3150 Variable Attenuator can be remotely controlled either by:

 a GPIB interface (through a GPIB cable connected to the GPIB port), or

 an RS-232 interface (through a serial cable connected to the serial

port)

The commands used in both protocols are the same and are described in the following pages. When the Variable Attenuator is being remotely controlled, Remote appears in the lower left corner of the display.

Note: If you have already designed a GPIB program to control an attenuator from

EXFO’s IQS Series (IQS-3100 or IQS-3150), you can reuse sections for the FVA-3150.

Setting Up the Variable Attenuator for Remote Control

To remotely control the Variable Attenuator, you need to set a GPIB address or activate the RS-232 port from the FVA-3150 front panel.

To set up the Variable Attenuator for remote:

1. Press Setup.

2. Use the left/right arrows to select GPIB-RS.

Variable Attenuator 45

Controlling Your Variable Attenuator Remotely

GPIB setting

GPIB address

RS-232 setting

Setting Up the Variable Attenuator for Remote Control

To select remote command mode:

1. If you have select GPIB-RS as a command mode, you only need to set

the address.

2. If you want to select the RS-232 mode, press ENTER.

3. Use the up and down arrows to reach RS-232 (before setting GPIB

address 1 or GPIB address 30).

4. Press ENTER.

5. To exit the Setup menu, press the Setup button.

46 FVA-3150

Controlling Your Variable Attenuator Remotely

GPIB Setting

GPIB address

Setting Up the Variable Attenuator for Remote Control

To select a GPIB address:

1. Once you selected GPIB as a command mode, you can set the GPIB

address you want.

2. Press ENTER. The bottom part of the displays will start flashing.

3. Using the up and down arrows, select the GPIB address you want.

Variable Attenuator 47

Controlling Your Variable Attenuator Remotely

Communication Parameters

Note: EOS means End of String. EOI means End or Identify.

For GPIB Communication

Terminate Read on EOS Yes

Set EOI with EOS on Writes Yes

Type of comparison on EOS 8-bits

EOS byte 0Ah

Sends EOI at end of Writes Yes

GPIB primary address 10

GPIB secondary address None

For RS-232 Communication

EOS bytes 0Ah

Baud rate 9600 bps

Parity None

Data bits 8 bits

Stop bits 1 bits

Flow control None

Activation see Setting Up the Variable Attenuator for

Remote Control on page 45

48 FVA-3150

Controlling Your Variable Attenuator Remotely

Standard Status Data Structure

The following page illustrates the four common status and enable registers as defined by IEEE 488.2. This diagram is a useful aid in understanding the general commands and how a service request (SRQ) is generated. The four registers are:

 Standard Event Status Register (ESR)

 Standard Event Status Enable Register (ESE)

 Status Byte Register (STB)

 Service Request Enable Register (SRE)

Bit ESR ESE STB SRE

0 Operation

Complete

Operation Complete

Source Status Source Status

1 Request Control Request Control

2 Query Error Query Error Error Bit

3 Device-

Dependent Error

DeviceDependent Error

Questionable Status

4 Execution Error Execution Error Event Status Bit Event Status Bit

5 Command Error Command Error Message

Available

6 User Request User Request Master Summary

Status

Message Available

Request Service/Master Summary Status

7 Power On Power On Operation Status Operation Status

Variable Attenuator 49

Controlling Your Variable Attenuator Remotely

Standard Event Status Register (ESR)

Standard Event Status Enable Register (ESE)

Status Byte

(STB)

Service Request Enable Register (SRE)

5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 5 4 3 2 1 0

ESB MAV EB

ESB MAV

RQS

MSS

Service Request

Generation

{

Output Queue not Empty

read by serial poll

read by *STB?

PON

OPC

URQ

RQCQYE

DDE

EXECME

PON

OPC

URQ

RQCQYE

DDE

EXECME

Standard Status Data Structure

50 FVA-3150

Controlling Your Variable Attenuator Remotely

Command Structure

An SRQ is forced when a bit is set in the STB and at the same time the corresponding SRE bit is set. When the SRQ is generated, the RQS bit is set to 1 and remains set until read by a serial poll. Once the RQS is read, it returns to 0.

Command Structure

The GPIB and RS-232 commands follow the guidelines determined by the Standard Commands for Programmable Interface (SCPI) consortium. For example, the command syntax

OUTP[:STAT]<wsp><boolean>

is used to control the FVA-3150 shutter.

In this particular example:

 OUTP identifies that the command is a part of the OUTPut subset

of commands;

 STAT is a keyword that defines the function of the command;

 [ ] indicates that a keyword or a parameter is optional;

 <wsp> indicates that a space is required and

 <boolean> is the command parameter.

All keywords must be UPPERCASE characters separated by a colon. A typical command would be

OUTP:STAT 1

This command instructs the Variable Attenuator to optically open the shutter.

Note: It is recommended to retrieve the response immediately after each query.

Variable Attenuator 51

Controlling Your Variable Attenuator Remotely

“

;

<Device dependent

“

information>

Error Messages

System and device-specific errors are managed by the FVA-3150 Variable Attenuator. The generic format for error messages is illustrated in the following figure.

As shown in the above figure, the message contains three parts: the error number, error description, and device-dependent information. All error messages are stacked in a FIFO buffer. When there is at least one message in the buffer, bit 2 of the Status Byte Register is set to 1. Use the SYST:ERR?, ERR?, or LERR? command to read the most recent message. The error message buffer is initialized when starting the Variable Attenuator, when executing the *CLS command, or by reading the last message stored in the buffer.

52 FVA-3150

Controlling Your Variable Attenuator Remotely

SCPI Management Errors (System Errors)

Error

Number

Description Probable Cause

–100 “Command Error.” An error occurred while validating a

command.

–101 “Undefined Header.” Unknown command.

–102 “Missing Parameter.” A command parameter is missing.

–103 “Parameter Not Allowed.” An extra parameter is present.

–104 “Data Type Error.” Invalid parameter format.

–200 “Execution Error.” An error occurred while executing a

command.

–300 “Device Dependent Error.” A command has taken longer than

expected to complete execution.

–300 “Invalid Attenuation.” A command has attempted to set the

internal attenuation to an invalid value.

–300 “Invalid Offset.” The reference value parameter entered

is out of range.

–300 “Program Running.” A command that will halt the currently

running program has been received, or an attempt has been made to override a program setting.

–300 “Invalid Wavelength.” The entered wavelength parameter is

out of range.

–300 “Invalid Delay Time.” The entered delay parameter is out of

range.

–300 “Invalid Duration Time.” The entered duration time parameter is

out of range.

Variable Attenuator 53

Controlling Your Variable Attenuator Remotely

1234 5

6789

RS-232 Connector Pinout

Error

Number

Description Probable Cause

–300 “Invalid Program Step.” The entered program step parameter is

out of range.

–300 “Invalid Program

Attenuation.”

The entered program attenuation parameter is out of range.

–300 “Invalid CAL Factor.” The entered calibration factor

parameter is out of range.

–400 “Query Error.” An error occurred while accessing the

output queue.

–500 “System Error.” System is out of memory.

RS-232 Connector Pinout

The RS-232 connector (serial port) at the back of the Variable Attenuator uses a DTE pinout configuration.

Pin Description Direction

2 Receive (Rx) Input

3 Transmit (Tx) Output

5 Signal ground (Gnd) —

54 FVA-3150

7 Maintenance

To help ensure long, trouble-free operation:

 Always inspect fiber-optic connectors before using them and clean

them if necessary.

 Keep the unit free of dust.

 Clean the unit casing and front panel with a cloth slightly dampened

with water.

 Store unit at room temperature in a clean and dry area. Keep the unit

out of direct sunlight.

 Avoid high humidity or significant temperature fluctuations.

 Avoid unnecessary shocks and vibrations.

 If any liquids are spilled on or into the unit, turn off the power

immediately, disconnect from any external power source, remove the batteries and let the unit dry completely.

Use of controls, adjustments, and procedures for operation and maintenance other than those specified herein may result in hazardous radiation exposure.

WARNING

Variable Attenuator 55

Maintenance

Push

Tur n

Pull

Cleaning EUI Connectors

Regular cleaning of EUI connectors will help maintain optimum performance. There is no need to disassemble the unit.

If any damage occurs to internal connectors, the module casing will have to be opened and a new calibration will be required.

To clean EUI connectors:

1. Remove the EUI from the instrument to expose the connector

baseplate and ferrule.

IMPORTANT

2. Moisten a 2.5 mm cleaning tip with one drop of isopropyl alcohol (alcohol may leave traces if used abundantly).

3. Slowly insert the cleaning tip into the EUI adapter until it comes out on the other side (a slow clockwise rotating movement may help).

4. Gently turn the cleaning tip one full turn, then continue to turn as you withdraw it.

56 FVA-3150

Cleaning EUI Connectors

5. Repeat steps 3 to 4 with a dry cleaning tip.

Note: Make sure you don’t touch the soft end of the cleaning tip.

6. Clean the ferrule in the connector port as follows:

6a. Deposit one drop of isopropyl alcohol on a lint-free wiping cloth.

IMPORTANT

Isopropyl alcohol may leave residues if used abundantly or left to evaporate (about 10 seconds).

Avoid contact between the tip of the bottle and the wiping cloth, and dry the surface quickly.

6b. Gently wipe the connector and ferrule.

6c. With a dry lint-free wiping cloth, gently wipe the same surfaces to

ensure that the connector and ferrule are perfectly dry.

6d. Verify connector surface with a portable fiber-optic microscope

(for example, EXFO’s FOMS) or fiber inspection probe (for example, EXFO’s FIP).

Maintenance

WARNING

Verifying the surface of the connector WHILE THE UNIT IS ACTIVE WILL result in permanent eye damage.

7. Put the EUI back onto the instrument (push and turn clockwise).

8. Throw out cleaning tips and wiping cloths after one use.

Variable Attenuator 57

Maintenance

Cleaning Detector Ports

Regular cleaning of detectors will help maintain measurement accuracy.

Always cover detectors with protective caps when unit is not in use.

To clean detector ports:

1. Remove the protective cap and adapter (FOA) from the detector.

2. If the detector is dusty, blow dry with compressed air.

3. Being careful not to touch the soft end of the swab, moisten a cleaning

tip with only one drop of isopropyl alcohol.

Alcohol may leave traces if used abundantly. Do not use bottles that distribute too much alcohol at a time.

IMPORTANT

4. While applying light pressure (to avoid breaking the detector window), gently rotate the cleaning tip on the detector window.

5. Repeat step 4 with a dry cleaning tip or blow dry with compressed air.

6. Discard the cleaning tips after one use.

58 FVA-3150

Maintenance

Recalibrating the Unit

Manufacturing and service center calibrations are based on the ISO/IEC 17025 Standard, which states that calibration documents must not contain a recommended calibration interval, unless this has been previously agreed upon with the customer.

Validity of specifications depends on operating conditions. For example, the calibration validity period can be longer or shorter depending on the intensity of use, environmental conditions and unit maintenance. You should determine the adequate calibration interval for your unit according to your accuracy requirements.

Under normal use, EXFO recommends calibrating your unit every year.

Variable Attenuator 59

Maintenance

Recycling and Disposal (Applies to European Union Only)

Recycle or dispose of your product (including electric and electronic accessories) properly, in accordance with local regulations. Do not dispose of it in ordinary garbage receptacles.

This equipment was sold after August 13, 2005 (as identified by the black rectangle).

 Unless otherwise noted in a separate agreement between EXFO and a

customer, distributor, or commercial partner, EXFO will cover costs related to the collection, treatment, recovery, and disposal of end-of-lifecycle waste generated by electronic equipment introduced after August 13, 2005 to an European Union member state with legislation regarding Directive 2002/96/EC.

 Except for reasons of safety or environmental benefit, equipment

manufactured by EXFO, under its brand name, is generally designed to facilitate dismantling and reclamation.

For complete recycling/disposal procedures and contact information, visit the EXFO Web site at www.exfo.com/recycle.

60 FVA-3150

8 Troubleshooting

Ver.

Mfg. date

P/N

S/N Made in Canada QST442B

465 Godin Avenue Vanier (Quebec) G1M 3G7 CANADA

**************** A

January 2020

542392-3D

Fiber

Connector code

FVA-3150-XX-XX

Contacting the Technical Support Group

To obtain after-sales service or technical support for this product, contact EXFO at one of the following numbers. The Technical Support Group is available to take your calls from Monday to Friday, 8:00 a.m. to 7:00 p.m. (Eastern Time in North America).

For detailed information about technical support, visit the EXFO Web site at

www.exfo.com.

Technical Support Group

400 Godin Avenue Quebec (Quebec) G1M 2K2 CANADA

To accelerate the process, please have information such as the name and the serial number (see the product identification label—an example is shown below), as well as a description of your problem, close at hand.

1 866 683-0155 (USA and Canada) Tel.: 1 418 683-5498 Fax: 1 418 683-9224

support@exfo.com

Variable Attenuator 61

Troubleshooting

Transportation

Maintain a temperature range within specifications when transporting the unit. Transportation damage can occur from improper handling. The following steps are recommended to minimize the possibility of damage:

 Pack the unit in its original packing material when shipping.

 Avoid high humidity or large temperature fluctuations.

 Keep the unit out of direct sunlight.

 Avoid unnecessary shocks and vibrations.

62 FVA-3150

9 Warranty

General Information

EXFO Inc. (EXFO) warrants this equipment against defects in material and workmanship for a period oftwo years from the date of original shipment. EXFO also warrants that this equipment will meet applicable specifications under normal use.

During the warranty period, EXFO will, at its discretion, repair, replace, or issue credit for any defective product, as well as verify and adjust the product free of charge should the equipment need to be repaired or if the original calibration is erroneous. If the equipment is sent back for verification of calibration during the warranty period and found to meet all published specifications, EXFO will charge standard calibration fees.

The warranty can become null and void if:

 unit has been tampered with, repaired, or worked upon by

unauthorized individuals or non-EXFO personnel.

 warranty sticker has been removed.

IMPORTANT

 case screws, other than those specified in this guide, have been

removed.

 case has been opened, other than as explained in this guide.

 unit serial number has been altered, erased, or removed.

 unit has been misused, neglected, or damaged by accident.

THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL EXFO BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.

Variable Attenuator 63

Warranty

Liability

EXFO shall not be liable for damages resulting from the use of the product, nor shall be responsible for any failure in the performance of other items to which the product is connected or the operation of any system of which the product may be a part.

EXFO shall not be liable for damages resulting from improper usage or unauthorized modification of the product, its accompanying accessories and software.

64 FVA-3150

Warranty

Exclusions

EXFO reserves the right to make changes in the design or construction of any of its products at any time without incurring obligation to make any changes whatsoever on units purchased. Accessories, including but not limited to fuses, pilot lamps, batteries and universal interfaces (EUI) used with EXFO products are not covered by this warranty.

This warranty excludes failure resulting from: improper use or installation, normal wear and tear, accident, abuse, neglect, fire, water, lightning or other acts of nature, causes external to the product or other factors beyond the control of EXFO.

IMPORTANT

EXFO will charge a fee for replacing optical connectors that were damaged due to misuse or bad cleaning.

Certification

Exclusions

EXFO certifies that this equipment met its published specifications at the time of shipment from the factory.

Variable Attenuator 65

Warranty

Service and Repairs

EXFO commits to providing product service and repair for five years following the date of purchase.

To send any equipment for service or repair:

1. Call one of EXFO’s authorized service centers (see EXFO Service

2. If equipment must be returned to EXFO or an authorized service

3. If possible, back up your data before sending the unit for repair.

4. Pack the equipment in its original shipping material. Be sure to include

5. Return the equipment, prepaid, to the address given to you by support

Centers Worldwide on page 67). Support personnel will determine if the equipment requires service, repair, or calibration.

center, support personnel will issue a Return Merchandise Authorization (RMA) number and provide an address for return.

a statement or report fully detailing the defect and the conditions under which it was observed.

personnel. Be sure to write the RMA number on the shipping slip. EXFO

will refuse and return any package that does not bear an RMA number.

Note: A test setup fee will apply to any returned unit that, after test, is found to

meet the applicable specifications.

After repair, the equipment will be returned with a repair report. If the equipment is not under warranty, you will be invoiced for the cost appearing on this report. EXFO will pay return-to-customer shipping costs for equipment under warranty. Shipping insurance is at your expense.

Routine recalibration is not included in any of the warranty plans. Since calibrations/verifications are not covered by the basic or extended warranties, you may elect to purchase FlexCare Calibration/Verification Packages for a definite period of time. Contact an authorized service center (see EXFO Service Centers Worldwide on page 67).

66 FVA-3150

Warranty

EXFO Service Centers Worldwide

If your product requires servicing, contact your nearest authorized service center.

EXFO Headquarters Service Center

400 Godin Avenue Quebec (Quebec) G1M 2K2 CANADA

EXFO Europe Service Center

Omega Enterprise Park, Electron Way Chandlers Ford, Hampshire S053 4SE ENGLAND

EXFO Telecom Equipment (Shenzhen) Ltd.

3rd Floor, Building 10, Yu Sheng Industrial Park (Gu Shu Crossing), No. 467, National Highway 107, Xixiang, Bao An District, Shenzhen, China, 518126

1 866 683-0155 (USA and Canada) Tel.: 1 418 683-5498 Fax: 1 418 683-9224

quebec.service@exfo.com

Tel.: +44 2380 246810 Fax: +44 2380 246801

europe.service@exfo.com

Tel: +86 (755) 2955 3100 Fax: +86 (755) 2955 3101

beijing.service@exfo.com

Variable Attenuator 67

A Technical Specifications

SPECIFICATIONS

SINGLEMODE CONFIGURATIONS

Description without monitor port with monitor port Models FVA-3150-B FVA-3150-BM

Fiber type (μm) 9/125 9/125 Wavelength range (nm) 1250 to 1650 1250 to 1650 Maximum attenuation (dB)

*65 *65

Insertion loss

c, d

Typical (dB) 1.0 1.5

Maximum (dB) 1.5 2.2 Attenuation setting resolution, typical (dB) ±0.002 ±0.002 Attenuation linearity (dB)

±0.1 ±0.1

Attenuation repetability (dB), 2 m

±0.01 ±0.01 Spectral uniformity, 1510 nm to 1605 nm (dB)g±0.05 ±0.05 Spectral uniformity, 1450 nm to 1630 nm, typical (dB)g±0.09 ±0.09 PDL, peak to peak (dB)

0.15 0.2

Return loss, typical (dB)

c, i

60 60 Maximum input power (dBm) 23 23 Settling time, including command 90 (for 0.1 dB step) 90 (for 0.1 dB step) processing time, typical (ms)

Transition speed, typical (dB/s) up to 23 up to 23 Shutter isolation (dB) >100 >100 Monitor ouput, typical (dB)

N/A 12.8

MULTIMODE CONFIGURATIONS

Description without monitor port with monitor port Models FVA-3150-C, D FVA-3150-CM, DM

Fiber type (μm) 50/125, 62.5/125 50/125, 62.5/125 Wavelength range (nm) 700 to 1350 700 to 1350 Maximum attenuation (dB)

*65 *65 Insertion loss

c, d

Typical (dB) 1.3 1.5

Maximum (dB) 2.0 3.0 Attenuation setting resolution, typical (dB) ±0.002 ± 0.002 Attenuation linearity (dB)

±0.1 ± 0.1

Attenuation repetability (dB)

±0.01 ± 0.01

Return loss, typical (dB)

c, d

40 40 Maximum input power (dBm) 20 20 Settling time, including command 90 (for 0.1 dB step) 90 (for 0.1 dB step) processing time, typical (ms)

Transition speed, typical (dB/s) up to 23 up to 23 Shutter isolation (dB) >100 >100 Monitor ouput, typical (dB)

NA 12.8

Notes

a. Valid at 23 °C ± 1 °C. b. Valid at 1550 nm and below. c. Measured at 1310 nm and 1550 nm for singlemode units and at 850 nm for multimode units. d. Excluding connectors. e. Measured at 1310 nm and 1550 nm (up to 60 dB) for singlemode units and at 850 nm and 1300 nm (up to 50 dB) for multimode units, with non-polarized light. f. Up to 45 dB attenuation. g. For 20 dB attenuation relative to 0 dB attenuation h. Up to 20 dB attenuation at 1550 nm. i. For FC/APC connectors. j. Includes time for command via GPIB, interpretation and attenuation settling: 185 ms for 1 dB step; 3 s for full range. k. Ratio between output port and monitor port, expressed in dB.

IMPORTANT

The following technical specifications can change without notice. The information presented in this section is provided as a reference only. To obtain this product’s most recent technical specifications, visit the EXFO Web site at www.exfo.com.

Variable Attenuator 69

Technical Specifications

GENERAL SPECIFICATIONS

Size (H X W X D) 117 mm X 222 mm X 333 mm (45/8 in X 8 3/4 in X 13 1/8 in) Weight 2.6 kg (5.8 lb) Temperature Operating 0 °C to 40 °C (32 °F to 122 °F)

Storage –40 °C to 70 °C (–40 °F to 158 °F)

Relative humidity 0 % to 80 % non-condensing

Instrument Drivers

LabVIEW™ drivers and SCPI commands.

Remote Control

GPIB (IEEE-488.1, IEEE-488.2), RS-232.

Standard Accessories

User guide, Certificate of Compliance, Certificate of Calibration and AC power cord.

70 FVA-3150

B Remote Control Commands

IEEE 488.2 Required Commands

The Variable Attenuator recognizes the main commands identified in IEEE-488.2. These commands are fully explained on the following pages.

Command Function

*CLS Clear status command

*ESE Standard event status enable command

*ESE? Standard event status enable query

*ESR? Standard event status register query

*IDN? Identification query

*OPC Operation complete command

*OPC? Operation complete query

*RST Reset command

*SRE Service request enable command

*SRE? Service request enable query

*STB? Read status byte query

*TRG Trigger command

*TST? Self-test query

*WAI Wait to continue command

The commands are fully explained in the following pages.

Variable Attenuator 71

Remote Control Commands

IEEE 488.2 Required Commands

Description This command sets the contents of the Standard Event Register

(ESR), the Status Byte Register (STB), and the Error Queue (ERR) to zero. This command is commonly used to clear the status registers before enabling SRQ. Note that the output queue, Standard Event Status Enable Register (ESE), and Service Request Enable Register (SRE) are not affected.

Syntax *CLS

Note The CLR command is equivalent to the *CLS command. Both

give the same result.

Description This command is used to set bits in the Standard Event Status

Enable Register (ESE) to a new value (default value is 255). The contents of the ESE register are logically ANDed with the ESR register. A non zero result will set the Event Summary Bit (ESB) of the Status Byte Register. This command is useful for selecting which events may generate an SRQ.

*CLS

*ESE

Syntax *ESE<wsp><value>

Parameter The <value> parameter must be between 0 and 255.

*ESE?

Description This query reads the contents of the Event Status Register.

Syntax *ESE?

Response Binary integer with a value between 0 and 255.

72 FVA-3150

Remote Control Commands

IEEE 488.2 Required Commands

*ESR?

Description This query reads the contents of the Standard Event Register.

Syntax *ESR?

Response Binary integer with a value between 0 and 255.

*IDN?

Description This query reads the FVA-3150 identification string.

Syntax *IDN?

Response “EXFO FVA-3150-XX-XX x.x.x.x”, where XX-XX is the current

product model and x.x.x.x is the current product version.

Note The SYST:VERS? and IDN? commands are equivalent to the

*IDN? command. They give the same result.

*OPC

Description This command causes the FVA-3150 to generate the operation

complete message in the Standard Event Status Register (ESR) when all pending selected FVA-3150 operations have been finished.

Syntax *OPC

Example *OPC,*IDN?

Variable Attenuator 73

Remote Control Commands

IEEE 488.2 Required Commands

Description This query puts an ASCII 1 in the output queue when the

contents of the input queue has been processed.

Syntax *OPC?

Response “1”

Note The OPC? command is equivalent to the *OPC? command.

Both give the same result.

Description This command empties the step response list. It is only seen

when it is part of another multiple command. In the example below, by adding this command after *IDN?, you will not be able to access the answer. The *RST, in this instance, erases the identification string. In addition, this command performs the following operations:

 Returns to initial state before command is sent, and not

necessarily to previous settings.

 Forces the device to enter into an Operation Complete

Command Idle State (OCIS).

 Forces the device to enter into an Operation Complete

Query Active State (OQIS).

 Initializes previous responses unless there has been a

program message terminator preceded by an *RST.

*OPC?

*RST

Syntax *RST

Example *IDN?,*RST<NL>

74 FVA-3150

Remote Control Commands

IEEE 488.2 Required Commands

*SRE

Description This command sets bits in the Service Request Enable Register

(default value is 255) and enables the corresponding bit in the Status Register. The command can be used to select which events can initiate a service request.

Syntax *SRE<wsp><value>

Parameter The <value> parameter must be between 0 and 255.

*SRE?

Description This query returns the contents of the Service Request Enable

Syntax *SRE?

Response Binary integer between 0 and 255.

*STB?

Description This query returns the contents of the Status Byte Register.

Syntax *STB?

Response A binary integer between 0 and 255.

Note The STB? command is equivalent to the *STB? command. Both

give the same result.

Variable Attenuator 75

Remote Control Commands

IEEE 488.2 Required Commands

Description This command will trigger any event that was suspended and is

waiting for a trigger.

Syntax *TRG

Parameters None

Note This command has no effect on the FVA-3150.

Description This query initiates an internal self-test and returns a binary

value indicating the results of the test.

Syntax *TST?

Response A binary value

“0” if the test is completed without error

“1” if the test is completed with errors

*TRG

*TST?

*WAI

Description This command prevents the FVA-3150 from processing any

further commands until the No-Operation-Pending Flag is set. All pending operations must be complete before processing another command.

Syntax *WAI

Parameters None

Note This command has no effect on the FVA-3150.

76 FVA-3150

Remote Control Commands

IEEE 488.2 Required Commands

The FVA-3150 Variable Attenuator also recognizes commands that can only be used with RS-232 communication. These commands are summarized below.

Command Function

*LOK Set Remote Lockout programming state

*LOK? Remote Lockout programming state query

*LOK

Description This command is used to lock and unlock the FVA-3150 keypad.

Once the FVA-3150 keypad is locked, no external input can interfere with the GPIB communication. The only way to unlock the keypad is to use the *LOK command again or turn off the unit.

Syntax *LOK <wsp><data>

Parameters The <data> parameter can be “1” to lock the keypad or “0” to

unlock the keypad.

Example *LOK 1

Note When the keypad is locked, the unit will beep twice if any key is

pressed on the keypad. The Remote indicator appears in the lower left corner of the display while the unit is being controlled remotely.

This command can only be used when working with RS-232 communication.

Variable Attenuator 77

Remote Control Commands

IEEE 488.2 Required Commands

Description This query reads the FVA-3150 keypad lock state.

Syntax *LOK?

Response “1” if the FVA-3150 keypad is locked

“0” if the FVA-3150 keypad is unlocked

Example *LOK?

Note This command can only be used when working with RS-232

communication.

*LOK?

78 FVA-3150

Remote Control Commands

Specific commands-Quick Reference Command Tree

Parameter/

Response

Description

ATT

Command

<±99.999 [DB] | MIN|MAX> set attenuation

ATT? (± 99.999) obtain attenuation

CAL

<±99.999> set offset

CAL? (± 99.999) obtain offset

<0|1> activate shutter

D? (0|1) obtain shutter state

DISP DIMM <LO | HI | OFF> adjust display

intensity

DIMM? <LO | HI | OFF> obtain display

intensity

Fiber

<1|2> set fiber type

Fiber? (1|2) obtain fiber type

INP ATT

<±99.999 [DB] | MIN|MAX> set attenuation

ATT? (± 99.999) obtain attenuation

OFFS

<±99.999 [DB]> set a reference value

DISP set ref. to display

OFFS? (±99.999) read reference value

STEP 0.01<step<50 set step

CATA? list of available steps obtain step list

Variable Attenuator 79

Remote Control Commands

Specific commands-Quick Reference Command Tree

Command

Parameter/

Response

Description

STEP? 0.01<step<50 obtain current step

WAVE

<9999.9 [NM]> set wavelength

(9999.9) obtain wavelength

OUTP APM <OFF|ON|0|1> set Absolute or

Reference

APM? (0|1) is it in Absolute

mode?

[STAT] <OFF|ON|0|1> activate shutter

[STAT]

(0|1) obtain shutter state

PROG SEL ATT ±99.999 set atten. parameter

DELA <999,59,59 set delay parameter

DURA <999,59,59 set duration

parameter

STAT <0 | 1 | START | STOP> control the program

STAT? (0|1) obtain program state

STEP <100 set step parameter

WVL

<9999.9 [NM]> set wavelength

WVL? (9999.9) obtain wavelength

a. Valid parameters are determined by the type of module.

b. This command is HPIB-compatible.

80 FVA-3150

Remote Control Commands

Specific commands-Quick Reference Command Tree

ATTenuation

Description This command sets the attenuation to a specific value. The valid

range of values depends on the configuration of the FVA-3150 and on the current wavelength. The difference with the current attenuation must be of at least 0.002 dB for the new attenuation step size to be valid.

Syntax ATT<wsp><value>[<wsp>DB]

Variable Attenuator 81

Remote Control Commands

value actual attenuation=

value actual attenuation reference value (INP:OFFS?)–=

value actual attenuation wavelength-specific offset+=

Specific commands-Quick Reference Command Tree

Parameters The <value> parameter can be

 “MIN” (to set the FVA-3150 to the minimum setting for the

current wavelength)

 “MAX” (to set the FVA-3150 to the maximum setting for the

current wavelength)

 a valid attenuation value followed by the units [DB]. Note

that, depending on the current measurement mode, the <value> parameter takes different values.

In Absolute mode:

In Reference mode:

In Offset mode:

Therefore, when in Reference or Offset mode, the range of the accepted values for the <value> parameter will change according to the current reference or offset value.

Example ATT –15.350 DB

Note This command cannot be issued while a program is running.

The ATT command is equivalent to the INP:ATT command. Both give the same result.

82 FVA-3150

Remote Control Commands

response actual attenuator general offset (CAL?)+=

response

actual

attenuation

reference value

INP:OFFS?

general offset

(CAL?)

+–=

response

actual

attenuation

wavelength-specific

offset

general offset++=

Specific commands-Quick Reference Command Tree

ATTenuation?

Description This query returns a value corresponding to the CAL parameter

value added to either the current attenuation setting, the minimum attenuation, or the maximum attenuation setting.

Syntax ATT? [<wsp><value>]

Parameters The <value> parameter is optional and can be

“MIN” to obtain the minimum setting for the current wavelength

“MAX” to obtain the maximum setting for the current wavelength

Response The attenuation value in the format “99.999”. The units are dB.

Note that, depending on the current measurement mode, the response will include different parameters:

In Absolute mode:

In Reference mode:

In Offset mode:

Example ATT? MIN

Note The ATT? command is not equivalent to the INP:ATT?

command.

Variable Attenuator 83

Remote Control Commands

Specific commands-Quick Reference Command Tree

Description This command stores an offset value that will be applied to all

wavelengths in Absolute, Reference, and Offset modes. This offset value will be included in the measurement returned by ATT? but will not be taken into account on the FVA-3150 display. This offset value is deleted when the FVA-3150 is turned off.

Syntax CAL<wsp><value>[<wsp><DB>]

Parameters The <value> parameter must be a valid attenuation value in

the format “±99.999”. The units (DB) are optional.

Example CAL 99.999 DB

Description This query returns the offset value that is applied to all

wavelengths in Absolute, Reference, and Offset modes.

CAL

CAL?

Syntax CAL?

Response The offset value that is applied to all wavelengths in Absolute,

Reference, and Offset modes in the format “±99.999”. The units are dB.

Note This offset value is included in the measurement returned by

ATT? but is not taken into account on the FVA-3150 display.

Example CAL?

84 FVA-3150

Remote Control Commands

Specific commands-Quick Reference Command Tree

Description This command controls the shutter, which can block optical

continuity.

Syntax D<wsp><numeric>

Parameters The <numeric> parameter can be

“0” to disable the shutter

“1” to enable the shutter

Example D 1

Note This command cannot be issued while a program is running.

Description This query returns the current shutter state.

Syntax D?

Response The shutter state in the format

“0” if the shutter is optically disabled

“1” if the shutter is optically enabled

Example D?

Variable Attenuator 85

Remote Control Commands

Specific commands-Quick Reference Command Tree

Description This command is used to adjust the intensity of the FVA-3150

display (high or low) or to turn off the display without turning off the unit.

Syntax DISP:DIMM<wsp><data>

Parameters The <data> parameter can be “HI”, “LO”, or “OFF”.

Example DISP:DIMM OFF

Note When the display is turned off by this command, any key

pressed on the FVA-3150 keypad will return the display to high intensity. To prevent this, lock the FVA-3150 keypad with the *LOK command.

EXFO FVA-3150 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Certification Information

Main Features

Front Panel

Back Panel

Available Models

Typical Applications

Main Concept

Conventions

2 Safety Information

Laser Safety Information

Electrical Safety Information

Installing your FVA-3150 Variable Attenuator in a Rackmount

Turning the Variable Attenuator On and Off

Accessing Menus

Selecting the Display Intensity

Locking Control Key Access

Managing the Wavelength Shortlist

Selecting the Attenuation

Selecting and Using an Attenuation Display Mode

Saving and Recalling a Configuration

Cleaning and Connecting Optical Fibers

Installing the EXFO Universal Interface (EUI)

Performing an Attenuation Routine

Operating the Shutter

Setting Up the Variable Attenuator for Remote Control

Communication Parameters

Standard Status Data Structure

Command Structure

Error Messages

SCPI Management Errors (System Errors)

RS-232 Connector Pinout

7 Maintenance

Cleaning EUI Connectors

Cleaning Detector Ports

Recalibrating the Unit

Recycling and Disposal (Applies to European Union Only)

8 Troubleshooting

Contacting the Technical Support Group

Transportation

9 Warranty

General Information

Liability

Exclusions

Certification

Service and Repairs

EXFO Service Centers Worldwide

A Technical Specifications

B Remote Control Commands

IEEE 488.2 Required Commands

Specific commands-Quick Reference Command Tree