EXFO FVA-3100-BEA Single-Mode Variable Optical Attenuator with APC Interface

EXFO FVA-3100-BEA Single-Mode Variable Optical Attenuator

The EXFO FVA-3100-BEA is a precision variable optical attenuator designed for controlled signal-level adjustment in single-mode fiber optic test systems. It provides accurate, repeatable attenuation for optical component characterization, receiver testing, system loss simulation, instrument calibration, power-meter linearity testing, and telecommunications research.

The BEA configuration combines the FVA-3100-B single-mode optical platform with an EXFO APC universal connector interface. The instrument uses 9/125 µm single-mode fiber and covers wavelengths from 1200 nm to 1650 nm, supporting common optical test applications near 1310 nm, 1490 nm, 1550 nm, and 1625 nm.

The FVA-3100-B provides wavelength-dependent maximum attenuation reaching at least 100 dB between 1200 nm and 1350 nm. It provides at least 80 dB from 1350 nm to 1600 nm and at least 70 dB from 1600 nm to 1650 nm. Attenuation is adjustable with 0.005 dB resolution for precise optical-level control.

Typical insertion loss is only 1.5 dB, helping preserve the available optical power and system loss budget. Standard GPIB and RS-232 interfaces enable remote operation from a compatible computer or automated test station, while the programmable sequence function supports repeatable attenuation profiles for bit-error-rate testing and other automated procedures.

Features and Benefits of the EXFO FVA-3100-BEA

• Single-mode optical configuration: Uses 9/125 µm fiber for compatible telecommunications and laboratory applications.
• Wide wavelength coverage: Supports optical signals from 1200 nm to 1650 nm.
• High maximum attenuation: Provides wavelength-dependent attenuation reaching at least 100 dB.
• Fine setting resolution: Allows attenuation to be adjusted in 0.005 dB increments.
• Low insertion loss: Provides 1.5 dB typical and 1.8 dB maximum insertion loss under the documented conditions.
• Accurate attenuation control: Provides ±0.1 dB linearity under the specified calibration and measurement conditions.
• Excellent repeatability: Supports attenuation-setting repeatability within ±0.03 dB.
• Low polarization-dependent loss: Provides 0.2 dB maximum peak-to-peak PDL at documented 20 dB and 50 dB attenuation settings.
• APC universal interface: The EA configuration supports compatible angled physical-contact optical connections.
• High optical input capability: Accepts input power up to +25 dBm under the documented conditions.
• High shutter isolation: Provides more than 100 dB of optical isolation when the shutter is active.
• Three attenuation modes: Supports absolute, relative, and X+B attenuation displays.
• Programmable operation: Stores repeatable sequences containing as many as 100 attenuation steps.
• Long programmable dwell times: Supports dwell times as long as 1000 hours per attenuation step.
• Remote communication: Includes standard GPIB and RS-232 interfaces for automated test integration.

1200 nm to 1650 nm Wavelength Range

The EXFO FVA-3100-BEA supports optical signals across wavelengths from 1200 nm to 1650 nm. This range covers several important single-mode transmission regions used in fiber optic telecommunications, optical component manufacturing, laboratory testing, and network equipment development.

The broad wavelength range allows the attenuator to support measurements near 1310 nm and 1550 nm as well as compatible applications at 1490 nm and 1625 nm. The instrument is calibrated at 1310 nm and 1550 nm for its single-mode fiber configuration.

The source, patch cords, removable connector adapters, device under test, detectors, receivers, and other equipment in the optical path should support the selected wavelength.

Wavelength-Dependent Attenuation Range

The maximum available attenuation depends on the operating wavelength. From 1200 nm to 1350 nm, the FVA-3100-B provides at least 100 dB of attenuation. From 1350 nm to 1600 nm, it provides at least 80 dB. From 1600 nm to 1650 nm, it provides at least 70 dB.

This broad attenuation capability supports receiver sensitivity testing, weak-signal simulation, component loss evaluation, system loss-budget testing, and controlled reduction of amplified optical signals.

The attenuation range should not be confused with shutter isolation. The optical shutter provides more than 100 dB of isolation and is intended to interrupt the optical path rather than provide a calibrated attenuation setting.

0.005 dB Attenuation Resolution

The FVA-3100-BEA provides 0.005 dB attenuation-setting resolution. This fine adjustment supports applications where small and repeatable optical-level changes are required.

Attenuation can be changed manually using user-defined increments or direct on-display value editing. The instrument can also be controlled remotely through GPIB or RS-232 for automated optical-level sweeps and production test sequences.

The setting resolution represents the smallest programmable increment. Actual optical uncertainty also depends on attenuation linearity, repeatability, source stability, wavelength, connector condition, polarization, patch-cord loss, and the measurement reference plane.

Low Insertion Loss

Typical insertion loss for the FVA-3100-B is 1.5 dB, with a documented maximum of 1.8 dB. These values are measured at 1310 nm and 1550 nm using the documented single-mode test configuration.

Low insertion loss helps preserve optical power and measurement dynamic range, especially in systems containing several switches, couplers, patch cords, adapters, or other passive components.

The total loss through the complete test system includes the attenuator, removable connector adapters, patch cords, mating connectors, and all other devices in the optical path.

Attenuation Linearity and Repeatability

Attenuation linearity is specified at ±0.1 dB under the documented conditions. The specification applies using a light source with 0.002 dB stability over a 15-minute period, wavelength accuracy of ±0.5 nm, non-polarized light, a calibrated wavelength, and attenuation settings up to 60 dB.

Maximum attenuation repeatability is ±0.03 dB. Repeatable optical settings are important for receiver testing, calibration procedures, production screening, and automated measurements that revisit the same attenuation points.

For best results, the optical source and attenuator should be allowed to stabilize before precision measurements are recorded. Fiber routing and connectors should remain mechanically stable throughout the measurement sequence.

Attenuation Display Modes

The FVA-3100 provides three attenuation display and operating modes:

• Absolute mode: Displays attenuation including the instrument insertion loss.
• Relative mode: Displays attenuation relative to the established 0.00 dB reference level.
• X+B mode: Displays attenuation relative to a user-selected reference value.

These modes allow the instrument to be adapted to different test procedures. Absolute mode is useful when total path attenuation is required, while relative and X+B modes support comparative measurements and user-defined reference planes.

Programmable Attenuation Sequences

The programmable mode allows the FVA-3100 to cycle through a repeatable sequence of as many as 100 attenuation steps. Each step can have a programmed dwell time of up to 1000 hours.

This capability is useful for automated bit-error-rate testing, receiver response measurements, long-duration stability tests, optical-level cycling, and production qualification.

A computer is not required for every programmed sequence once the applicable values are configured in the instrument. More complex test procedures can be controlled through the standard GPIB or RS-232 interfaces.

GPIB and RS-232 Remote Control

The FVA-3100 includes standard GPIB and RS-232 communication interfaces. These connections support remote control from a compatible computer, test station, or automated measurement system.

Remote control can coordinate the attenuator with optical sources, power meters, bit-error-rate testers, receivers, spectrum analyzers, transceiver fixtures, switches, and other supported equipment.

LabVIEW drivers and OCX controls were available for the FVA-3100 platform. Compatibility with a specific operating system, software revision, interface controller, and automation environment should be verified before integration.

EA APC Universal Optical Interface

The EA option identifies the EXFO APC universal optical interface. A compatible removable EUI connector adapter is required to complete the optical connection.

Available removable EUI adapters include DIN 47256, SC, FC narrow key, and E-2000 connector formats. The specific EUI adapter installed on the individual instrument should be confirmed before patch cords are selected.

Only compatible APC patch cords should be connected to the EA interface. APC and non-angled PC or UPC connectors must not be directly intermated because their ferrule geometries are incompatible.

Optical Input Power and Shutter Isolation

The maximum optical input power is +25 dBm. Optical input above this level may damage the instrument and can cause attenuation linearity to exceed the specified limits.

An input level of +25 dBm corresponds to approximately 316 mW. The limits of external fibers, adapters, receivers, power meters, and devices under test must also be observed.

The internal shutter provides more than 100 dB of optical isolation. The shutter can interrupt the signal during device changes, dark measurements, receiver protection, and automated test sequences.

Typical Applications

• Optical receiver sensitivity testing
• Bit-error-rate testing
• Single-mode component characterization
• Optical system loss simulation
• Power meter linearity measurement
• Optical instrument calibration
• Transceiver testing
• Optical amplifier testing
• Fiber transmission-system evaluation
• Automated optical-level sweeps
• Production and quality-control testing
• Telecommunications research and development

Product Overview

Brand	EXFO
Model	FVA-3100-BEA
Product Series	FVA-3100
Product Category	Variable Optical Attenuator
Fiber Type	9/125 µm single-mode fiber
Optical Interface	EXFO APC universal interface
Wavelength Range	1200 nm to 1650 nm
Maximum Attenuation	Wavelength dependent, reaching at least 100 dB
Communication Interfaces	GPIB and RS-232
Primary Application	Precise single-mode optical attenuation and automated signal-level control

 

Optical Specifications

Specification	Details
Fiber Type	9/125 µm single-mode fiber
Wavelength Range	1200 nm to 1650 nm
Wavelength Resolution	0.1 nm
Maximum Attenuation from 1200 nm to 1350 nm	At least 100 dB
Maximum Attenuation from 1350 nm to 1600 nm	At least 80 dB
Maximum Attenuation from 1600 nm to 1650 nm	At least 70 dB
Attenuation Resolution	0.005 dB
Linearity	±0.1 dB under the documented conditions
Maximum Repeatability	±0.03 dB
Typical Insertion Loss	1.5 dB
Maximum Insertion Loss	1.8 dB
Maximum Input Power	+25 dBm
Shutter Isolation	Greater than 100 dB

 

Polarization and Return-Loss Specifications

Specification	Details
Maximum PDL at 20 dB Attenuation	0.2 dB peak-to-peak
Maximum PDL at 50 dB Attenuation	0.2 dB peak-to-peak
Typical Return Loss for the B Optical Configuration	At least 55 dB with the documented connector arrangement
Optical Interface Finish	APC universal interface for the EA configuration

 

Programming and Communication Specifications

Function	Details
Attenuation Modes	Absolute, relative, and X+B
Maximum Program Steps	100 attenuation steps
Maximum Dwell Time	1000 hours per step
Standard Remote Interfaces	GPIB and RS-232
Available Instrument Drivers	LabVIEW drivers and OCX controls
Installation Format	Benchtop or optional 19-inch rack mounting

 

Compatible Removable EUI Adapters

Adapter Model	Connector Format
EUI-28	DIN 47256
EUI-91	SC
EUI-89	FC narrow key
EUI-95	E-2000

 

Physical and Environmental Specifications

Specification	Details
Height	11.7 cm, or 4 5/8 in
Width	22.2 cm, or 8 3/4 in
Depth	33.3 cm, or 13 1/8 in
Weight	2.6 kg, or 5.8 lb
Operating Temperature	0 °C to 40 °C
Storage Temperature	-40 °C to 70 °C
Relative Humidity	10% to 80%, non-condensing, decreasing linearly to 50% at 40 °C

 

Measurement Setup

The FVA-3100-BEA should be installed on a stable laboratory bench or in a compatible 19-inch rack using the appropriate optional hardware. Adequate clearance should be maintained for optical patch cords, communication cables, power, and ventilation.

The correct removable EUI adapter should be installed for the connector format being used. Both optical ports, removable adapters, and mating patch cords should be inspected and cleaned before connection.

The input source should remain below the documented +25 dBm maximum. When connecting a sensitive receiver or detector, the attenuator should initially be set to a high attenuation value before the optical source is enabled.

The attenuation can then be reduced gradually while optical power and the device under test are monitored. The instrument should be allowed to stabilize before precision attenuation measurements are recorded.

Comprehensive Functional and Performance Testing

The EXFO FVA-3100-BEA receives comprehensive functional and performance testing before shipment. Evaluation may include AC power operation, startup, display response, keypad controls, rotary adjustment controls, shutter operation, wavelength entry, attenuation modes, manually selected attenuation settings, and programmable sequences.

Communication testing may include GPIB and RS-232 operation. Remote attenuation commands, status queries, program control, and interaction with compatible automation software may be evaluated when suitable hardware is available.

Optical testing may include input-to-output continuity, insertion loss, representative attenuation settings, attenuation range, repeatability, linearity, polarization-dependent loss, return loss, and shutter isolation using appropriate calibrated equipment.

The APC optical interfaces, removable EUI adapters, display, controls, communication ports, enclosure, AC connection, labels, protective caps, and installed accessories may be inspected for contamination, damage, corrosion, or excessive wear.

The exact testing scope depends on the installed EUI adapters, available optical sources, calibrated power meters, return-loss equipment, polarization test equipment, communication hardware, and requested wavelengths and attenuation points.

Calibration Before Shipment

When technically applicable and selected, the EXFO FVA-3100-BEA can be calibrated or performance-verified before shipment. Evaluation may include insertion loss, attenuation accuracy, attenuation linearity, repeatability, wavelength response, polarization-dependent loss, return loss, and shutter isolation.

Calibration documentation should identify the attenuator model and serial number, EA connector interface, installed EUI adapters, test wavelength, input optical power, attenuation settings, reference patch cords, measurement equipment, environmental conditions, recorded results, and applicable measurement uncertainty.

Buyers requiring formal calibration should specify the desired wavelengths, attenuation points, optical input level, connector configuration, return-loss tests, certificate format, recorded data, and required measurement uncertainty before purchase.

Buyer Considerations

Buyers should confirm the complete model as EXFO FVA-3100-BEA. The B designation identifies 9/125 µm single-mode fiber, while EA identifies the EXFO APC universal optical interface.

This configuration does not include the monitor output associated with the BM and BWM models. A monitor port should not be assigned to the FVA-3100-BEA unless a separate physical option is specifically verified.

The product listing should identify the removable EUI adapters, protective caps, GPIB cable, RS-232 cable, rack hardware, power cord, instruction manual, Certificate of Compliance, software, test records, and calibration documentation that are included.

Only the EXFO FVA-3100-BEA variable attenuator and accessories specifically identified in the product listing should be considered included.

Why Buy from AssetRelay?

AssetRelay supplies professional equipment and product solutions for fiber optic, telecommunications, optical testing, photonics, laboratory, production, inspection, electronic testing, RF/microwave, and technical research applications. The EXFO FVA-3100-BEA provides precise single-mode optical attenuation for component manufacturers, receiver developers, telecommunications laboratories, production facilities, system integrators, universities, and research organizations.

Buyers should review the single-mode B configuration, EA APC interfaces, installed EUI adapters, attenuation range, insertion loss, repeatability, shutter operation, GPIB and RS-232 communication, functional test results, calibration status, and included accessories before purchase.