Buyer Guide · FTTH / ODN

PLC Splitter Ratio Selection Guide: Loss Budget, Package and RFQ Lines

Choose a PLC splitter ratio from the optical loss budget of your PON, not from the number of homes alone: every doubling of outputs adds about 3 dB of loss. Once the ratio fits the budget, choose the package for the place it will be installed, then the connector, fiber and lead lengths. This guide gives the loss figures, a worked budget example, a package comparison and the line format we use to quote 1x8, 1x16, 1x32 and 2xN splitters.

Send Splitter RFQ View PLC Splitters

Published 2026-07-17 · Updated 2026-11-10 · By the Lumafyn Technical Team

Rack-mounted fiber patch panel with rows of aqua LC adapters

Why the Ratio Is a Loss-Budget Decision

A passive splitter divides the optical power of one input fiber across N outputs. The ideal loss per output is 10 × log₁₀(N) dB, so a 1x2 loses about 3 dB and each further doubling adds another 3 dB. Real devices add excess loss and some unevenness between ports, which is why datasheets publish a maximum insertion loss above the theoretical figure.

PLC splitter ratio and insertion loss
Ratio	Theoretical split loss	Example published max IL (no connectors)*
1x2	3.0 dB	3.8 dB
1x4	6.0 dB	7.1 dB
1x8	9.0 dB	10.2 dB
1x16	12.0 dB	13.5 dB
1x32	15.1 dB	16.8 dB
1x64	18.1 dB	20.2 dB

*Example values from a publicly available PLC splitter datasheet (see sources). They show the typical gap between theory and a real device; they are not Lumafyn product data. Connectorized versions add the loss of each mated connector pair. Your quotation and test report state the values for the exact configuration you order.

2xN splitters (2x8, 2x16, 2x32) have two inputs, typically used for protection or to bring in a second feeder. Their per-output loss is similar to the 1xN version with the same output count.

Worked Example: Does a 1x32 Fit the Budget?

GPON optics are grouped by power-budget class in ITU-T G.984.2; Class B+ allows 28 dB and Class C+ 32 dB between OLT and ONT. A simple check for a single-stage 1x32 design:

Example GPON loss budget, single-stage 1x32
Item	Assumption	Loss
Splitter	1x32, published max IL example	16.8 dB
Feeder + drop fiber	12 km singlemode at an assumed 0.35 dB/km (1310 nm)	4.2 dB
Connectors	4 mated pairs at an assumed 0.3 dB each	1.2 dB
Splices	6 fusion splices at an assumed 0.1 dB each	0.6 dB
Total		22.8 dB
Margin vs Class B+ (28 dB)		5.2 dB

The assumptions are illustrative; use your own route lengths, the attenuation of the fiber you buy and the loss limits in your design rules. If the margin is thin, consider a lower ratio, a two-stage design (for example 1x4 in a cabinet feeding 1x8 at the building) or higher-class optics. A two-stage 1x4 + 1x8 serves 32 outputs like a single 1x32 but splits the loss across two locations and adds one more connector point.

Common Ratios and Where They Are Used

Typical splitter ratio by application
Ratio	Typical use	What to check
1x2 / 1x4	First stage in a cascaded design, small branches, test links	Which second-stage ratio follows it
1x8	Small MDU floors, rural clusters, second stage after a 1x4	Number of outputs actually lit
1x16	Mid-size MDU or FAT/NAP boxes	Box capacity and drop count
1x32	Single-stage GPON distribution, the most common FTTH design	Loss budget and reach
1x64	Dense designs with higher-class optics	Optics class and margin
2xN	Protected feeders or dual-OLT designs	Which input is primary

Choose the Package for the Installation Point

The same splitter chip is sold in very different housings. Quote the package that fits the place it will live, and say where that is.

PLC splitter package types
Package	Leads	Best fit
Bare fiber	250 µm fibers, no connectors	Inside splice trays of closures where the tray protects the fibers
Mini steel tube (blockless)	0.9 mm tight-buffer leads, spliced or connectorized	Compact boxes and trays with limited space
ABS box	2.0 or 3.0 mm leads, usually connectorized	Wall boxes, cabinets and ODFs where leads need protection
LGX / plug-in cassette	Adapters on the faceplate	Rack frames and cabinets that need quick replacement
Rack mount (1U/2U)	Adapters on the front panel	Central office or POP rooms with many splitters
Fiber distribution box splitter	Pre-installed in a terminal box	Outdoor FAT/NAP points

"Insert type" or "LGX" describes a package class, not a universal size. When a splitter must fit an existing frame or box, send the frame model or the slot dimensions.

Blue SC simplex fiber adapter with dust cap and laser warning label

Connector, Fiber and Lead Lengths

Connector and polish. SC/APC is the usual choice in PON networks because the angled end face keeps back-reflection low; LC/APC or LC/UPC appears in dense cabinets. State input and output connectors separately if they differ.
Fiber. Bend-insensitive G.657.A1 or A2 is common for splitter leads in boxes; G.652.D is common in rack modules. State it if your network standard requires one.
Lead lengths. Record input and output lengths separately, with the tolerance you need. A 1 m output lead and a 1.5 m input lead on the same splitter is a normal request, but it has to be written down.
Lead diameter. 0.9 mm, 2.0 mm or 3.0 mm; this must match the box routing.
Port identification. Output numbering, colored boots or labels if technicians must trace outputs.

Test Items to Ask For

For acceptance, ask for per-port records rather than one summary number. Common items on a PLC splitter test sheet:

PLC splitter test items
Item	Why it matters
Insertion loss per output	Feeds directly into your loss budget; check the worst port, not only the average
Uniformity	Difference between best and worst output; matters more as N grows
Return loss	Back-reflection, especially with connectorized leads
Polarization dependent loss (PDL)	Stability of loss with polarization
Wavelength range	PON uses several wavelengths; confirm the stated operating range covers them
End-face inspection	For connectorized versions, clean and undamaged ferrules

Generic requirements for passive splitters are described in ITU-T G.671 and Telcordia GR-1209-CORE, with reliability testing in GR-1221-CORE. If your operator specifies one of these, put it in the RFQ so the quotation states how it will be met.

A Quote-Ready PLC Splitter Line Schedule

A short request such as "quote 1x8, 1x16 and 1x32 splitters" leaves most of the fields open. Give each configuration its own row; never combine ratios on one line, even when quantities are small.

PLC splitter RFQ fields
Field	What to send	Example
Line ID and revision	Your line number, BOM revision and date	SPL-02, Rev A
Ratio	1xN or 2xN	1x16
Package	Bare, steel tube, ABS box, LGX, rack	ABS box
Input side	Connector/polish, lead diameter and length	SC/APC, 2.0 mm, 1.5 m
Output side	Connector/polish, lead diameter and length	SC/APC, 2.0 mm, 1.0 m
Fiber	G.657.A1/A2, G.652.D	G.657.A1
Installation point	Box, cabinet, ODF or closure reference	FAT-B12
Connected lines	Related ODF, pigtail, adapter or drop cable line IDs	ODF-01, DROP-05
Commercial	Quantity, labels, packing, destination	200 pcs, export carton, Mexico

Leave a field marked "to be confirmed" rather than guessing; it is faster to settle an open field before quoting than to re-quote after a wrong assumption.

Common PLC Splitter RFQ Mistakes

Ratio without package. A 1x8 can be a bare-fiber device or a rack cassette; prices and fit are completely different.
One length for both sides. Input and output leads are often different lengths.
Mixing ratios on one line. Each ratio, package and connector combination needs its own quantity.
No installation point. Without the box or ODF reference nobody can confirm the splitter fits.
Budget not checked. Choosing 1x64 without confirming optics class and reach.

FAQ

PLC Splitter Ratio FAQ

How much loss does a 1x32 PLC splitter add?

The theoretical split loss is about 15 dB; real devices add excess loss, and published maximum values are typically around 16.5–17 dB without connectors. Add the loss of each connector pair if the splitter is connectorized, and use the value on your test report for the final budget.

Is 1x32 or 1x64 better for GPON?

1x32 is the most common single-stage GPON ratio because it fits comfortably inside a Class B+ (28 dB) budget for typical reach. 1x64 adds about 3 dB more loss and usually needs higher-class optics or shorter routes. Run the budget for your own route before choosing.

What is the difference between PLC and FBT splitters?

PLC splitters are made on a planar waveguide chip and give even splitting across a wide wavelength range, which suits PON networks with many outputs. FBT (fused biconical taper) splitters are made by fusing fibers; they are common for low ratios and custom unequal splits.

Which package should I choose?

Choose by installation point: bare fiber or steel tube inside splice trays and compact boxes, ABS box for wall boxes and cabinets, LGX cassette or rack mount for central offices and ODF frames. Send the frame or box model when the splitter must fit existing hardware.

What information do you need to quote PLC splitters?

For each line: ratio, package, input and output connector and polish, lead diameter and lengths, fiber type, installation point, quantity and destination. A BOM revision and drawing help when splitters connect to ODFs or terminal boxes.

Sources and Further Reading

Standards and public references describe definitions and industry practice; they are not Lumafyn product data. Optical values, MOQ and lead time for your order are confirmed in your quotation and test records.