More than AC, DC or a manufacturer name
Will this model work on your layout?
Two products are not automatically compatible merely because both are labelled H0, TT or N. The nominal size initially describes the scale and model track gauge. The conductor system, current pickup, wheelsets, digital protocol, decoder interface, coupling and minimum radius must also work together.
In H0, the terms “AC” and “DC” are frequently used as convenient abbreviations. H0 AC normally describes a centre-conductor vehicle with a pickup shoe, whereas H0 DC usually describes a two-rail vehicle with electrically isolated wheel sides. DCC, mfx, Motorola and Selectrix are digital control languages. A locomotive can therefore understand DCC while still using centre-conductor current pickup.
Products from different manufacturers can be combined when their technical specifications match. Older vehicles, special circuit boards, lighting systems and feedback equipment may require additional work. This database therefore provides a preliminary result: directly compatible, compatible after checking or conversion, or unsuitable in the selected configuration.
Interactive preliminary check
Check compatibility in a few steps
Record the technical profile of your layout first and then enter the item you want to use. Unknown details deliberately produce a check notice rather than an unjustified approval.
Track, command stations and connector systems
Search systems, command stations and interfaces
Filter the overview by product group, gauge, manufacturer, protocol or interface name. The classification describes the technical core of each system but does not replace the complete product specification.
| Area | System or interface | Gauge | Electrical classification | Protocols | Compatibility core | Details |
|---|---|---|---|---|---|---|
| Track | Märklin H0 C Track | H0 | Centre conductor | Independent | For centre-conductor vehicles; not electrically identical to Trix C Track. | View C Track |
| Track | Märklin H0 K Track | H0 | Centre conductor | Independent | Centre-conductor track without fixed roadbed; plan transition geometry carefully. | View K Track |
| Track | Trix H0 C Track | H0 | Two-rail | Independent | Related geometry, but a different conductor system from Märklin C Track. | View Trix Range |
| Track | ROCO LINE H0 Track with Roadbed | H0 | Two-rail | Independent | For two-rail vehicles; check rail-profile height and transition geometry. | Compare Track Systems |
| Track | PIKO A-Track | H0 | Two-rail | Independent | Available with or without roadbed; align transitions to other systems carefully. | View PIKO A-Track |
| Track | Tillig TT Track | TT | Two-rail | Independent | Distinguish roadbed track from model track and compare joiners and rail profiles. | View Tillig TT Track |
| Track | Minitrix Track | N | Two-rail | Independent | N-gauge system; check turnout geometry and system-specific connectors. | View Minitrix Track |
| Track | Kato UNITRACK | N | Two-rail | Independent | Dedicated roadbed and connection system; transitions require suitable adapters. | View Kato UNITRACK |
| Track | Märklin Z Gauge Track | Z | Two-rail | Depends on the item | Small gauge: pay particular attention to wheel contacts, voltage and installation space. | View Z Gauge Track |
| Track | Märklin Gauge 1 Track | 1 | Two-rail | Vehicle-dependent | Large scale: check current demand, power supply, boosters, wiring and radius. | View Gauge 1 Track |
| Track | LGB G Gauge Track | G / IIm | Two-rail | Vehicle-dependent | 45 mm large-scale track; consider radius, outdoor use and current capacity. | View LGB Track |
| Command station | Märklin Central Station 3 | Several | Check separately from the vehicle conductor system | mfx, mfx+, MM, DCC | Multiprotocol station; size the power supply, output and track connection correctly. | CS3 Guide |
| Command station | Roco Z21 and z21 | Several | Typically focused on two-rail operation | DCC, model-dependent MM | Network and app control; check RailCom and feedback components separately. | Z21 Guide |
| Command station | PIKO SmartControl | Several | Typically focused on two-rail operation | DCC | For DCC decoders; verify Wi-Fi, accessory bus and output for the exact model. | SmartControl Guide |
| Command station | ESU ECoS | Several | Conductor system checked separately | DCC, MM, SX, M4 | Multiprotocol station; M4 provides an mfx-compatible operating mode. | ESU Brand World |
| Command station | Uhlenbrock Intellibox | Several | Conductor system checked separately | DCC, mfx, MM, SX | Multiprotocol and LocoNet functions; verify the precise Intellibox version. | Intellibox Guide |
| Command station | Lenz Digital plus | Several | Typically focused on two-rail operation | DCC | Modular DCC system; select XpressNet and ABC components deliberately. | Lenz Guide |
| Command station | ZIMO Digital System | Several | Output depends on the model | DCC and system functions | Compare DCC, RailCom and ZIMO functions across device generations. | ZIMO Guide |
| Command station | Massoth DiMAX | G / several | Large and garden railways | DCC | Designed for higher-current applications; plan power supplies and booster districts. | Massoth Brand World |
| Interface | NEM 651 | N, TT and small vehicles | 6-pin connector | Independent of connector | Check pin allocation, orientation, current capacity and available installation space. | NEM 651 Explained |
| Interface | NEM 652 | H0 and others | 8-pin connector | Independent of connector | Check plug orientation, available functions and installation space. | NEM 652 Explained |
| Interface | Next18 and Next18S | N, TT and H0 | Compact plug connection | Independent of connector | Do not assume that Next18 and Next18S are interchangeable. | Compare Interfaces |
| Interface | PluX12, PluX16 and PluX22 | TT, H0 and others | PluX connector family | Independent of connector | Compare the exact PluX variant, pin allocation and required function outputs. | PluX22 Explained |
| Interface | 21MTC | H0 and others | 21-contact circuit-board connection | Independent of connector | Check logic-level and amplified outputs on the vehicle circuit board. | 21MTC Explained |
| No matching entries were found. Change the search term or filters. | ||||||
Technical decision instead of a brand assumption
Six levels determine safe operation
Work through these criteria in order. Compatibility at only one level is not enough to approve the complete combination.
Nominal size and model track gauge
H0, H0m and H0e use the same scale but different model track gauges. Similar distinctions exist between standard, metre, narrow and field railway gauges in other nominal sizes.
Two-rail, centre conductor and current pickup
Powered vehicles require the correct current pickup. A common digital protocol cannot replace a pickup shoe, electrically isolated wheel sides or suitable internal wiring.
Wheelsets, turnouts and feedback
Coaches and wagons may roll mechanically but still cause problems at turnouts, feedback sections or interior-lighting contacts. Wheel insulation, flange profile and back-to-back dimensions remain important.
DCC, mfx, Motorola and Selectrix
The command station and decoder require at least one common control protocol. RailCom adds feedback to DCC but requires suitable components throughout the relevant signal chain.
NEM interfaces and decoder output
NEM 651, NEM 652, Next18, PluX and 21MTC describe electrical connections, not the digital language. Motor current, function outputs, pin allocation and available space must also be checked.
Coupling, vehicle length and minimum radius
A standard coupling pocket makes replacement easier but does not guarantee matching height or correct close-coupling movement. Long vehicles require sufficiently generous curves and clearances.
Standard gauge, narrow gauge and large scale
Classify gauges from Zm to IIm correctly
The database covers common European nominal sizes, narrow-gauge suffixes and a selection option for special or manufacturer-specific dimensions.
- Z and Zm
- N, Nm and Ne
- TT, TTm, TTe and TTf
- H0, H0m, H0e and H0f
- S gauge
- 0, 0m, 0e and 0f
- 1, 1m and 1e
- II, IIm, IIe, IIf and G
The suffix m commonly identifies a metre-gauge prototype, e a narrower narrow-gauge prototype and f a field or industrial railway. H0e is built to 1:87 scale but does not run on standard H0 track.
For Z, N and TT, available space, clean wheel-to-rail contact and carefully limited current are especially important. H0 offers a wide variety of two-rail, centre-conductor and narrow-gauge combinations. Gauge 0, Gauge 1 and G require more attention to vehicle weight, current demand, power supplies, cable cross-sections and radius.
Gauge alone does not determine whether a system is analogue or digital. DCC is used across many nominal sizes, mfx is widespread in the Märklin environment, and Selectrix is found particularly in older N- and TT-gauge systems. The decoder and command-station specifications are decisive.
On garden railways, distinguish the 45 mm model track gauge from the prototype represented by the model. G is commonly used for metre- and narrow-gauge models and should not automatically be treated as identical to standard-gauge Gauge 1.
Select technology that fits
Suitable product groups for conversion and expansion
Use complete product groups when selecting components. The following examples show typical combinations of command station, digital protocol and decoder interface. Always confirm the current product data before ordering.
Digital command stations and control systems
Select a command station first by the protocols used by your decoders, then by output, operating concept, feedback system, network connection and expansion bus.
Multiprotocol control
Märklin 60226 Central Station 3
Command station for mfx, mfx+, Motorola and DCC. Conductor system, approved power supply and required output remain separate checks.
Open Product DetailsNetwork-enabled digital system
Roco 10820 Z21 Digital Command Station
Command station with DCC, Motorola, network, app and RailCom functions. Select suitable feedback modules and system-bus components for the intended layout.
Open Product DetailsEight-pin retrofit
PIKO 56503 SmartDecoder XP 5.1
H0 decoder with an eight-pin NEM 652 connector and DCC, mfx and Motorola support. Compare motor current, available installation space and required function assignments.
Open Product DetailsDecoders, track, wheelsets and couplings
A conversion may require components from several product groups. A suitable decoder cannot compensate for an incorrect pickup shoe, unsuitable wheelsets or a different coupling mount.
Digital Command Stations
Compare command stations, handheld controllers and complete digital systems.
Decoders and Modules
Select by interface, protocol, gauge, motor load and required functions.
Track and Turnouts
Compare track systems, rail profiles, roadbeds, geometry and conductor types.
Wheelsets and Couplings
Check insulation, diameter, wheel spacing, coupling mount and replacement parts.
Brand worlds at Modellbahnshop
Manufacturers of track, digital and decoder technology
The manufacturer is a useful filter, but it is not a complete compatibility guarantee. Different gauges, conductor systems, interfaces and product generations may exist within a single brand.
Answers for a safe choice
Frequently asked questions about model railway compatibility
These answers cover common combinations of vehicles, track systems, command stations, decoders, wheelsets and coupling systems.
Can locomotives from different manufacturers run together?
Yes. When the nominal size, conductor system, current pickup and at least one digital protocol match, the manufacturer name is normally not an obstacle. Also compare the minimum radius and wheelset specification.
Do all H0 vehicles fit every H0 track system?
No. Two-rail and centre-conductor H0 systems must be distinguished. H0m, H0e and H0f use the same 1:87 scale but different model track gauges from standard H0.
Can a DCC locomotive run on a centre-conductor layout?
It can when the command station and decoder both support DCC and the locomotive has a suitable centre pickup. DCC compatibility alone does not replace the required pickup shoe or wheelset wiring.
Are Märklin C Track and Trix C Track identical?
No. Their appearance and geometry are related, but they use different electrical systems: Märklin C Track has a centre conductor, while Trix C Track is a two-rail system.
Can unlit H0 coaches and wagons roll on both systems?
Many can roll mechanically, but wheel insulation, flange dimensions, turnout geometry, feedback sections, axle pickups and a possible later installation of interior lighting must be checked.
Does PluX22 automatically mean that a decoder supports DCC and mfx?
No. PluX22 defines the electrical connection. A decoder may support only DCC or several formats. Read the protocol and interface specifications separately.
Which command station is suitable for a mixed fleet?
A multiprotocol station is often appropriate when the fleet contains DCC, mfx, Motorola or Selectrix decoders. Also compare operation, output, feedback bus, network functions and expansion options.
Can an analogue locomotive be placed directly on digital track?
A purely analogue locomotive should not be operated on digital track unless the manufacturer explicitly permits it. A conversion normally requires a suitable decoder and correct electrical isolation.
Can track from different manufacturers be connected?
It is often possible when the model track gauge and conductor system match. Rail profile, height, joiners, roadbed, geometry and power feeds still require suitable transitions.
Is a matching decoder plug enough?
No. Protocol support, motor current, function outputs, installation space, speaker connection, energy storage and the vehicle circuit board must also be compatible.
Plan the complete system
From compatibility check to a complete layout concept
Discover further guidance on gauges, digital technology, track planning, vehicles, maintenance, wiring and layout construction in the central English Model Railway Guide.
Go to the Model Railway Guide