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The EXFO ELS-50 is a professional dual-wavelength optical light source designed for fiber optic insertion loss testing in FTTH, telecom, and CATV networks. Trusted by field technicians worldwide, it delivers ±0.10dB output stability at both 1310nm and 1550nm — the two standard singlemode wavelengths — powered entirely by standard AA batteries for up to 60 hours of continuous operation. No charging, no proprietary packs. Just reliable, repeatable measurements all day in the field.
Pair it with the EXFO EPM-50 Optical Power Meter for a complete, matched insertion loss test set from a single trusted brand.
| Parameter | ELS-50 (Model 23BL) |
|---|---|
| Wavelengths | 1310nm / 1550nm (singlemode) |
| Output Power | ≥ −5 dBm |
| Power Stability | ±0.10 dB |
| Spectral Width | ≥ 5nm |
| Tone Generation | 270Hz / 1kHz / 2kHz |
| Battery Life | 60 hours (standard AA) |
| Connector | Interchangeable: FC, SC, ST, LC |
| Dimensions | 189 × 78 × 37 mm |
| Weight | 400g (0.9 lb) |
| Operating Temp | −10°C to +50°C |
| Warranty | 1 Year |
The ELS-50 is the light source half of a two-instrument optical loss test set (OLTS). It injects stable optical power into the fiber under test; a calibrated power meter (such as the EXFO EPM-50) at the far end measures received power. The difference — in dB — is the insertion loss of the fiber link. This test is required for:
The ELS-50 is engineered to pair with the EXFO FiberBasix EPM-50 Optical Power Meter. Together they form a complete, matched OLTS:
See our EXFO EPM-50 listing to complete your test set.
Q: What is the EXFO ELS-50?
A: The EXFO ELS-50 is a professional dual-wavelength optical light source that outputs stable optical power at 1310nm and 1550nm for fiber optic insertion loss testing. It is part of the EXFO FiberBasix series and is designed to pair with the EXFO EPM-50 power meter.
Q: What power meter is compatible with the EXFO ELS-50?
A: The ELS-50 is designed to pair with the EXFO FiberBasix EPM-50 Optical Power Meter for a complete insertion loss test set.
Q: How long does the battery last on the EXFO ELS-50?
A: The ELS-50 runs on standard AA batteries with 60 hours of continuous operation — over 2.5 days of uninterrupted field testing.
Q: What connector types does the EXFO ELS-50 support?
A: The ELS-50 features interchangeable connector adapters supporting FC, SC, ST, and LC connector types. The FC adapter is included; additional adapters are available separately.
Q: What is tone generation on the ELS-50 and how is it used?
A: The ELS-50 modulates its optical output at 270Hz, 1kHz, or 2kHz. When used with a compatible power meter or fiber identifier, this tone allows technicians to identify and trace specific fibers within a multi-fiber cable without interrupting live service.
Q: Is the EXFO ELS-50 suitable for FTTH testing?
A: Yes. The ELS-50 is widely used for FTTH/FTTx network installation and acceptance testing, verifying that fiber links meet operator loss budgets at both 1310nm and 1550nm before service activation.
Q: What is the output power stability of the EXFO ELS-50?
A: The ELS-50 delivers ±0.10dB power stability, ensuring consistent and repeatable insertion loss measurements across all test conditions and operating temperatures.
Q: What is included in the EXFO ELS-50 package?
A: The package includes the ELS-50 light source main unit, AA batteries, FC connector adapter, quick reference sticker, certificate of compliance, and soft carrying pouch.
Q: What warranty does the EXFO ELS-50 come with?
A: The ELS-50 comes with a 1-year warranty and certificate of compliance. For support or bulk/B2B pricing, contact us at info@cpostore.com.
