Product Overview

Sylvania Octron® Curvalume® 21878 (FBO31/835/XP/ECO) U-Bend Lamp — 31W | 3500K Neutral White | 2,725 Lumens | 1-Inch Leg Spacing

The Sylvania Octron® Curvalume® 800XP® Ecologic® 21878 (FBO31/835/XP/ECO) Lamp is a commercial-grade, high-efficiency compact U-bent fluorescent bulb engineered for commercial office troffers, 2x2 modular recessed ceiling grids, medical facilities, and retail environments. Delivering 2,725 initial lumens of crisp 3500K neutral white illumination, this 31-watt specialty tube features a tight 1-inch leg spacing profile and utilizes premium tri-phosphors to achieve an 82 CRI color accuracy baseline. Outfitted with standard G13 medium bi-pin bases and an ultra-low mercury fill weight, it provides an extended service life up to 28,000 hours when driven by approved high-frequency electronic control gear.

Wattage

31W

Energy Efficient

Shape Profile

U-Bend

1" Leg Spacing

Brightness

2,725

2,560 Mean lm

Color Render

82 Ra

3500K Neutral

Max Life

28,000

Hours on PRS

ADL Supply Expert Application & Replacement Guide

The Sylvania Curvalume® FBO31/835/XP/ECO U-bent fluorescent lamp is an established industry facility maintenance baseline specified heavily for compressed 2x2 troffer grids across corporate office centers, commercial retail floors, institutional classrooms, and hospital wings. Featuring a highly tight 1-inch leg center profile, it concentrates structural illumination over a compressed layout footprint, allowing procurement teams to preserve high light level thresholds without undergoing the full labor or upfront capital expenditure of full solid-state LED luminaire conversions.

Critical Open Circuit Voltage Thresholds and Socket Shunting Rules: Field electricians executing routine building upkeep sweeps must carefully evaluate host control parameters prior to finalized ordering. This 31-watt energy-saving bulb functions when driven by approved high-frequency electronic Instant Start, Rapid Start, or Programmed Rapid Start ballasts specifically calibrated to run T8 lamps with ballast factors ranging from 0.71 to 1.20.

However, installers must align socket mechanics to the starting type: if running on an Instant Start network, shunted lampholders are mandatory, requiring both socket contacts to be bridged down a single line. Conversely, if connecting to a Programmed Start layout, un-shunted lampholders are mandatory to keep the pin tracks completely isolated, allowing a dedicated low-voltage preheating current to condition the filaments safely before full ignition strikes. Reversing this configuration will short-circuit wiring networks or bypass cathode conditioning, accelerating end-blackening and triggering premature lamp failure.

Verify Before Installing

1-Inch Leg Spacing U-Bend — 550V RMS Open Circuit Voltage Checked — Regional Shipping Restrictions

This tube incorporates a tight 1.00" Inch leg space pitch with an overall maximum length of 22.6 inches—it cannot fit into wider 6-inch spacing Curvalume troffers. If exposed to heavy drafts or temperatures below 60°F (16°C), visual striation (a rhythmic swirling light pulse rolling down the tube) may occur. This behavior is a non-damaging thermodynamic reaction; raising ambient room temperatures back above baseline values will instantly stabilize the arc path.

State Delivery Restrictions: Due to strict regional environmental laws and mercury content caps, this fluorescent product cannot be legally sold or shipped to residential or commercial destinations inside CA, CO, HI, ME, MN, OR, RI, or VT.

Detailed Product Specifications

Brand Name: Sylvania (OSRAM Sylvania Group / Ledvance Corporate Division)
Product Series Line: Octron® Curvalume® 800XP® ECOLOGIC® Series
Sylvania Factory Product Order Code SKU: 21878
Manufacturer Description Nomenclature: FBO31/835/XP/ECO (Corrected raw title string link)
UPC Barcode Number (GTIN-12): 046135218781
Core Technology Class: Fluorescent Gaseous Discharge — T8 U-Bent Discharge Tube
Primary Control Requirement: T8 Calibrated Electronic Ballast (High-Frequency with 0.71 to 1.20 Ballast Factor)
Operational Power Draw: 31 Watts
Nominal Arc Operating Voltage: Ballast Managed (Nominal 137V AC operating voltage across gas column)
Continuous Operating Amperage Draw: 0.255 Amperes continuous current profile
Initial Luminous Brightness: 2,725 Lumens (Post standard 100-hour seasoning burn at 25°C)
Mean Luminous Lifecycle Output: 2,560 Lumens (Measured post the 40% operational life mark)
Color Temperature Configuration: 3500K Neutral White (835 Premium Tri-Phosphor Chemistry Blend)
Color Rendering Index (CRI): 82 Ra
Base Type Configuration: G13 Medium Bi-Pin Base (Two individual bases spaced on 1" leg centers)
U-Bend Structural Spacing Dimension: 1-Inch Leg Center-to-Center Spacing Spanning Inside Prongs
Nominal Tube Profile Diameter: T8 Shield (1.00" Inch / 25.4mm actual outer glass shield width)
Maximum Overall Length (MOL): 22.6" Inches structural width from base face to apex arc curve
Rated Average Service Lifespan (Instant Start 3-Hr Cycles): 15,000 Hours
Rated Average Service Lifespan (Programmed Start 3-Hr Cycles): 24,000 Hours
Rated Average Service Lifespan (Instant Start 12-Hr Continuous): 22,000 Hours
Rated Average Service Lifespan (Programmed Start 12-Hr Continuous): 28,000 Hours
Chassis Burn Position Limit: Universal — Operates reliably in any horizontal flat plane orientation

Operation, Safety & Mounting Compliance

High-Frequency Electronic Signal Transformation

When retrofitted onto modern high-efficiency electronic ballasts (such as Sylvania Quicktronic networks), this lamp operates at frequencies exceeding 40 kHz, completely eliminating stroboscopic eye fatigue and rolling shadows. This module interfaces seamlessly with the patented QUICK 60 system warranty platform. Integrated anti-striation control lines inside the ballast further stabilize the gas-discharge loops, preventing the visual shimmer or mercury sloshing common when drawing tubes inside cold rooms or drafty multi-tenant ducts.

Ecologic® Low-Mercury Dosing and Safe Bulk Recycling Protocols

Sylvania Ecologic® designs certify that this linear tube utilizes an advanced tri-phosphor chemical composition combined with a tightly metered internal heavy-metal mercury fill dose (limited to 3.5 mg weight profile). This structural configuration allows spent modules to cleanly pass the strict Federal Toxic Characteristic Leaching Procedure (TCLP) test protocols per NEMA guidelines, preventing high-density environmental pollution. However, as an mercury-containing device, spent bulbs must be securely routed to certified regional commercial electronic waste processing repositories during facility maintenance sweeps rather than discharged into municipal solid landfills.

Commercial Equipment Industry Cross-References

This premium 31W T8 1-inch U-bend bulb serves as a direct drop-in replacement or equivalent for the following lines:

GE Lighting Alternative: Ecolux F31T8/SPX35/U/1 / Order Code 15814
Philips Lighting Match: Advantage FB031/ADV835/1 / USA Catalog Product Code 428755
Satco Hygrade Reference: S6551 / Hygrade 31W 1-Inch U-Bend Series

Bulk Commercial Lighting Supply & Project Support

ADL Supply handles volume distribution shipments, multi-pack logistics, and contractor project quotes for procurement teams, schools, and warehouse facilities nationwide.

For specialized contractor pricing tiers, job-site pallet deliveries, or comprehensive submittal documentation, contact our support team directly at 1-800-235-3489. We are your commercial supply partners as an authorized wholesale Lighting Distributor In Doral, Florida.