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Model Number: OFL250-50U-ENG

The Noyes OFL250-50 is a 1550 nm single-mode OTDR with an integrated optical power meter (OPM), 1550 nm laser source (OLS), and visual fault locator (VFL) in a handheld package weighing only 0.8 kg (1.7 lb). With short dead zone and mid-range dynamic range performance, the OFL250-50 is ideal for troubleshooting dark single-mode fibers in local area, metro area, and FTTx networks.
The OFL250-50 provides automatic and manual setup, precision event analysis, 12-hour battery life, internal data storage, and USB connectivity. OTDR and OPM test ports are equipped with tool-free adapters, which can be changed in seconds. OTDR test results are saved as industry standard .SOR files, which can be transferred to a PC for viewing, printing, and analyzing with the supplied Windows® compatible software.


  • Rugged, handheld and light weight
  • 1.5m event dead zone
  • 26 dB dynamic range
  • Integrated OPM, OLS, VFL
  • Tool-free, switchable adapters for OTDR and OPM ports
  • Internal storage (>1000 OTDR traces in standard .SOR format)
  • High-contrast display is clear and bright in any lighting condition, including direct sunlight
  • Transfer test results to a PC via USB
  • Rechargeable 12-hour Li-Ion battery or AC Power
  • Windows compatible software to view, print, and archive test records


  • Locate cable cuts, open or high-loss splices, fiber bends, and high-loss/high-reflectance connections
  • Measure optical power (OPM port)
  • Short-range fault-location (VFL port)
  • Trace fibers and measure end-to-end loss at 1550 nm (working with a Noyes optical power meter or light source)
  • Identify fibers (working with a Noyes optical fiber identifier)


Emitter Type Laser
Safety Class Class I FDA 21 CFR 1040.10 and 1040.11,
IEC 60825-1: 2007-03
Fiber Type Single-mode
Center Wavelength 1550 nm
Wavelength Tolerance
± 20 nm
Dynamic Range (SNR=1)
26 dB
Event Dead Zone 1.5 m
Attenuation Dead Zone 7 m
Pulse Widths 5, 10, 30, 100, 300 ns, 1, 3, 10 μs
Range Settings 250 m to 256 km
Data Points Up to 16,000
Data Point Spacing 12.5 cm (range < 4 km),
Range/16,000 (range > 4 km)
Group Index of Refraction (GIR) 1.4000 to 1.6000
Distance Uncertainty (m) ± (1 + 0.005% x distance + data point spacing)
Trace File Format Bellcore GR-196 V.1.1
Trace File Storage Medium Internal memory (>1000 traces)
Data Transfer to PC USB cable
OTDR Modes Full Auto, End Locate, Expert, Live
1. Typical distance between the two points 1.5 dB down each side of a reflective spike caused by a -45 dB event using 5 ns pulse width.
2. Typical distance from event location to point where trace is within 0.5 dB of backscatter at 5 ns pulse width.


Optical Light Source

Emitter Type Class I FDA 21 CFR 1040.10 and 1040.11,
IEC 60825-1: 2007-03
Fiber Type Single-mode
Center Wavelength 1550 nm
Wavelength Tolerance ± 20 nm
Spectral Width (FWHM) 5 nm (max)
Internal Modulation 1 kHz, 2 kHz
Output Power Stability < ± 0.25 dB after 15 min
Output Power (nominal) – 3 dBm

Visual Fault Locator

Emitter Type Laser
Safety Class Class II FDA 21 CFR 1040.10 and 1040.11,
IEC 60825-1: 2007-03
Wavelength 650 nm
Output Power (nominal) 0.8 mW into single-mode fiber


Size (in boot) 19 x 11.2 x 4.7 cm (7.5 x 4.4 x 1.9 in)
Weight 0.8 kg (1.7 lb)
Operational Temperature -10 to +50°C, 0 to 95% RH (non-condensing)
Storage Temperature -20 to +60°C, 0 to 95% RH (non-condensing)
Power Rechargeable Li-Ion or AC adapter
Battery Life 12 hours, backlight ON, continuous operation
Display LCD, 320 x 240, 3.5 inch (89 mm), color, high-performance transflective with backlight and AR coating
Optical Power Meter
Calibrated Wavelengths 1310, 1490, 1550, 1625 nm
Detector Type Filtered InGaAs
Measurement Range +23 to - 45 dBm
Tone Detect Range +3 to -35 dBm
Wavelength ID range +3 to -35 dBm
Accuracy ± 0.25 dB
Resolution 0.01 dB
Measurement Units dB, dBm, mW, nW