Ubiquiti UACC-OM-QSFP28-SR4 100G SR4 Multi-Mode Optical Module
Overview
The Ubiquiti UACC-OM-QSFP28-SR4 is a QSFP28 form-factor optical transceiver that delivers 100 Gbps data rates over multi-mode fiber at 850 nm wavelength. This is a high-density interconnect module purpose-built for enterprise and carrier-class network infrastructure where QSFP28 optical uplinks are required. The 100-meter reach over cost-effective multi-mode cabling makes it suitable for campus backbones and data center interconnection where fiber distance and bandwidth density matter.
Key Features
- Dual-Rate Operation (40/100 Gbps): Supports both 40G and 100G line rates, giving you flexibility to deploy the module in mixed-speed network environments without requiring separate inventory. Useful if you're upgrading infrastructure incrementally rather than forking-lift replacing.
- 850 nm Multi-Mode Wavelength: Operating at 850 nm over OM3/OM4 multi-mode fiber keeps cable costs substantially lower than single-mode alternatives. For 100-meter reach, multi-mode fiber is the economics play — you trade distance for affordability and easier termination in campus environments.
- 100-Meter Maximum Reach: Covers typical data center pod-to-pod and building-to-building campus distances without requiring signal regeneration. Verify your actual fiber plant distance before specifying — 100 m is the hard limit; longer runs require single-mode modules or active inline equipment.
- MPO-12 Type B UPC Connector: Standardized fiber connector interface ensures interoperability with modern switching fabric. Type B orientation is the common standard for Ubiquiti and most vendor QSFP28 modules — confirm your switch uplink ports use Type B, not Type A.
- Low Power Draw (2.5 W Max): Thermal footprint is negligible in dense switch lineups. Unlike some older transceiver designs, you won't need to worry about cooling or power budgeting strain on your switch chassis — total power consumption stays well within typical optics budget allocations.
- CLASS 1 LASER PRODUCT Certification: Complies with IEC/EN 60825-1:2014 laser safety standards. This is not optional in regulated environments; the certification is present and documented, but fiber-end safety protocols (never look into fiber ends while powered) remain your responsibility during installation and troubleshooting.
Integration & Compatibility
The UACC-OM-QSFP28-SR4 is designed for Ubiquiti UniFi Cloud Gateway and compatible switching infrastructure that provides QSFP28 optical uplink ports. Typical deployments include data center fabric uplinks, campus fiber backbone segments, and high-speed network interconnection where you need to avoid electrical interference and achieve longer distances than copper cabling permits. Confirm your switch supports QSFP28 optics and that your fiber plant uses OM3 or OM4 multi-mode cable before purchase.
Deployment Considerations
Install and operate this module in climate-controlled network closets or data centers. The 0–70°C operating range is standard for indoor networking equipment — if your switch room lacks cooling or you're deploying near heat sources (HVAC exhausts, direct sunlight), derating may apply. Fiber connectors require periodic cleaning; MPO-12 end-face inspection and connector maintenance are mandatory before installation and during troubleshooting. Stock a few fiber cleaning supplies and an optical power meter if you deploy multiples of these modules.
Frequently Asked Questions
Q: Can I use the UACC-OM-QSFP28-SR4 with single-mode fiber?
A: No. This module is optimized for multi-mode fiber (OM3/OM4) at 850 nm. Single-mode fiber operates at different wavelengths (1310 nm, 1550 nm) and requires different transceiver modules. Installing this module with single-mode fiber will not work.
Q: What's the difference between SR4 and LR4 variants?
A: SR4 (Short Reach) operates at 850 nm over multi-mode fiber up to 100 m. LR4 (Long Reach) typically operates at 1310 nm over single-mode fiber for much longer distances (10 km+). Choose based on your fiber plant type and distance requirement.
Q: Does the UACC-OM-QSFP28-SR4 require firmware updates?
A: Optical transceivers are passive or semi-passive devices with no firmware. No updates are needed. Once installed in a compatible QSFP28 port, they operate immediately without configuration.
Q: Is there a Type A version of this module?
A: The UACC-OM-QSFP28-SR4 uses MPO-12 Type B UPC connectors. Confirm your switch supports Type B before ordering. Type A and Type B are not interchangeable physically.
Q: What is the warranty on this transceiver?
A: Warranty terms are not specified in the available documentation. Contact the manufacturer or your vendor for warranty and support details.
Q: Can I mix 40G and 100G speeds on the same switch with this module?
A: Yes. The UACC-OM-QSFP28-SR4 supports both 40G and 100G line rates. Your switch must support dual-rate operation on the same port or line card — verify your switch documentation for compatibility.
Ted PerryPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
The UACC-OM-QSFP28-SR4 is a straightforward play for campus fiber backbone work where you need 100G density without the cost and complexity of single-mode optics. At 2.5 W power draw and 100 m effective reach over OM3/OM4 multi-mode fiber, this module handles pod-to-pod and building-to-building interconnection efficiently. The dual-rate capability (40/100 Gbps) gives you a bit of runway if your switch infrastructure is mixed-generation.
Technical Highlights:
- 850 nm Multi-Mode Operation: Keeps fiber plant costs substantially lower than single-mode alternatives. OM3/OM4 cable is cheaper to install, easier to terminate, and tolerates slight bends better than single-mode — real advantages in campus runs where you're pulling through existing conduit.
- 100-Meter Effective Distance: Covers standard data center and campus segments without regeneration. Don't spec this for longer runs — if you need 500 m+ reach, you're into single-mode LR4 or longer-wavelength modules.
- Passive MPO-12 Connector: No active electronics in the connector itself, meaning no field programming, no pairing dance, no vendor lock-in. Swap it from one switch to another without reconfiguration.
Deployment Considerations:
- Confirm your switch supports QSFP28 and that the uplink ports accept Type B MPO-12 connectors. Type A and Type B are physically incompatible — a wrongly-ordered module is an expensive paperweight.
- Fiber-end cleanliness is non-negotiable. MPO-12 interfaces have tight tolerances; dust, fingerprints, or micro-scratches on ferrule ends cause signal loss or complete link failure. Budget for a fiber inspection scope and cleaning kit if you don't already own them.
- The 0–70°C operating window is tight for outdoor or semi-outdoor cabinets. If your switch room lacks reliable cooling, verify ambient conditions before installation.
Use the UACC-OM-QSFP28-SR4 for data center uplinks in OM3/OM4 fiber plants up to 100 m where you want 100G bandwidth without single-mode fiber cost. If your campus fiber is already single-mode or exceeds 100 m, look at longer-reach transceiver alternatives.
