EXFO EUI-91 SC OTDR Adapter – SC Connector for EXFO MAX-715B, MAX-720B, MAX-730, MAX-720, FTB-1 & FTB-2
The EXFO EUI-91 is the genuine SC OTDR port adapter designed for EXFO MAX-series and FTB-series OTDRs. It connects directly to the OTDR’s optical port and accepts standard SC connectors, enabling insertion loss, return loss, and fiber length measurements on SC-terminated fiber links — the most widely deployed connector type in FTTH, telecom OSP, and enterprise fiber networks.
When your EXFO OTDR’s SC adapter is worn, damaged, or missing, the EUI-91 is the correct OEM-specified replacement. A dirty or damaged OTDR adapter is one of the most common causes of poor OTDR traces, high dead zones, and inaccurate loss measurements — replacing it with the correct adapter restores measurement accuracy immediately.
Compatible EXFO OTDR Models
| Series | Compatible Models |
|---|---|
| EXFO MAX Series | MAX-715B, MAX-720, MAX-720B, MAX-730 |
| EXFO FTB Series | FTB-1, FTB-2 |
If you are unsure whether the EUI-91 is compatible with your specific EXFO OTDR model, please contact us before ordering and we will confirm compatibility.
Key Features
- SC Connector Interface: Accepts standard SC/PC and SC/APC connectors — the most common connector type in FTTH, PON, and telecom singlemode fiber networks.
- OEM EXFO Part – EUI-91: Correct OEM-specified adapter for EXFO MAX and FTB series OTDRs — ensures proper optical alignment and measurement accuracy.
- Direct OTDR Port Fit: Designed to connect directly to the EXFO OTDR optical port without adapters or modifications — plug-and-play replacement.
- Restores Measurement Accuracy: A worn or contaminated OTDR adapter increases the event dead zone and introduces measurement errors. Replacing with a new EUI-91 restores the OTDR’s specified performance.
- Compact & Lightweight: Fits in any OTDR carry case or tool bag — carry a spare EUI-91 for field use to avoid job site delays caused by a damaged adapter.
What Is an OTDR Adapter and Why Does It Matter?
An OTDR adapter (also called an OTDR connector interface or OTDR port adapter) is the removable optical interface that connects the OTDR’s internal optical port to the fiber under test. It determines which connector type the OTDR can accept — SC, FC, LC, ST, etc. The adapter is a wear item: repeated connector insertions gradually degrade the ceramic ferrule alignment sleeve, increasing insertion loss at the OTDR port and degrading trace quality.
Key reasons to replace a worn OTDR adapter:
- Increased event dead zone: A worn adapter increases reflectance at the OTDR launch point, extending the dead zone and masking near-end events
- Inaccurate loss measurements: Poor optical contact at the OTDR port introduces measurement uncertainty across the entire trace
- Contamination risk: A damaged adapter ferrule sleeve is harder to clean and more likely to contaminate the OTDR’s internal optical port
- Connector type flexibility: Swapping adapters allows the same OTDR to test SC, FC, LC, and ST fiber links — the EUI-91 is the SC adapter for this purpose
When to Replace Your EXFO OTDR SC Adapter
- OTDR traces show unusually high launch reflectance or extended dead zones
- Loss measurements are inconsistent or higher than expected on known-good fiber links
- The adapter ferrule sleeve is visibly worn, cracked, or contaminated and cannot be cleaned
- You need to switch from FC or LC testing to SC connector testing on the same OTDR
- Preventive replacement after high-volume field use (recommended every 500–1000 insertions)
Ideal Applications
- FTTH / PON network testing — SC connectors are the standard interface in FTTH OLT and ONT equipment; the EUI-91 enables direct OTDR testing of SC-terminated drop fibers
- Telecom OSP fiber characterization — insertion loss, return loss, and fiber length measurement on SC-terminated outside plant cables
- Enterprise and data center fiber testing — OTDR testing of SC-terminated structured cabling and backbone fiber
- OTDR adapter replacement and maintenance — restoring EXFO MAX or FTB OTDR measurement accuracy after adapter wear or damage
- Field spare — carrying a spare EUI-91 prevents job site delays caused by a damaged or lost SC adapter
Frequently Asked Questions
Q: What is the EXFO EUI-91?
A: The EXFO EUI-91 is an SC OTDR port adapter designed for EXFO MAX-series and FTB-series OTDRs. It connects to the OTDR’s optical port and accepts standard SC connectors for fiber optic testing.
Q: Which EXFO OTDR models is the EUI-91 compatible with?
A: The EUI-91 is compatible with the EXFO MAX-715B, MAX-720, MAX-720B, MAX-730, FTB-1, and FTB-2. If you are unsure about compatibility with your specific model, please contact us before ordering.
Q: What connector type does the EUI-91 accept?
A: The EUI-91 accepts SC connectors (SC/PC and SC/APC), the most widely deployed connector type in FTTH, PON, and telecom singlemode fiber networks.
Q: Why does my OTDR need a new SC adapter?
A: OTDR adapters are wear items. Repeated connector insertions degrade the ceramic ferrule alignment sleeve, increasing insertion loss at the OTDR port, extending the event dead zone, and reducing measurement accuracy. Replacing the adapter with a new EUI-91 restores the OTDR’s specified performance.
Q: Can I use the EUI-91 on EXFO OTDRs not listed above?
A: The EUI-91 is specified for the EXFO MAX and FTB series listed above. Compatibility with other EXFO OTDR models is not guaranteed. Please contact us with your OTDR model number to confirm before ordering.
Q: Is the EUI-91 an OEM EXFO part?
A: Yes. The EUI-91 is the OEM-specified SC adapter for the listed EXFO OTDR models, ensuring correct optical alignment and measurement accuracy.
Q: How many EUI-91 adapters come in one package?
A: Each package contains one (1) EUI-91 SC OTDR adapter. For bulk or B2B orders, please contact us at info@splicermarket.com for volume pricing.
Package Contents
- EXFO EUI-91 SC OTDR Adapter ×1