The Exfo FOS-125A is a portable LED light source purpose-built for fiber optic network installation and maintenance in field environments. It delivers stable output across dual wavelengths with switchable continuous wave and modulated signal modes, enabling both power/loss measurements and fiber identification tasks. The instrument combines compact dimensions with extended battery runtime, making it practical for technicians working across diverse site conditions.
Technical Specifications
Optical Performance
• Wavelengths: 1310 nm and 1550 nm
• Spectral Width: 70 nm FWHM (both wavelengths)
• Launch Power (typical):
– 9/125 µm fiber: -7 dBm
– 50/125 µm fiber: -20 dBm
Signal Modes
• Continuous Wave (CW) for power and loss measurements
• 2 kHz modulated signal for fiber identification
Power Supply
• 9 V battery or standard AC adapter
• Battery runtime: minimum 7 hours continuous operation
• Auto-off timer: 10 minutes
Physical & Mechanical
• Dimensions: 22.2 cm (H) × 10.3 cm (W) × 5.9 cm (D)
• Weight: 0.6 kg
• Shockproof PVC holster with carrying strap included
• Rigid carrying case provided
– Key Features
• EXFO Universal Interface for direct connection to compatible detectors
• Dual-wavelength operation addresses both short-reach and long-haul fiber testing
• Field-optimized form factor and protective accessories reduce setup time
• Battery-backed operation with extended hold time supports remote installations
– Typical Applications
• Fiber optic cable plant commissioning
• Maintenance and troubleshooting of installed networks
• Power loss budgeting during system design validation
• Non-destructive fiber identification in congested ducts or cable trays
– Compatibility & Integration
The FOS-125A integrates with EXFO’s ecosystem of optical test instruments via the Universal Interface, allowing pairing with compatible power meters and optical loss test sets. Included connector set (SC, ST, FC) supports standard industry fiber terminations.
