MTS Decoders FAQs

55040 MTS Function Decoder for Special Functions

This special decoder is designed for custom Multi-Train System applications, like MTS control of sound functions in older LGB locos. However, it can also be used in a wide variety of other loco applications.
Each 55040 can control two separate functions with two built-in relays. Up to four 55040s can be used together (eight functions total). Via DIP switches, you can select the mode for each terminal set: On/Off (with timed delay), synchronous flashing, asynchronous flashing, as well as the timing of the functions. The possibilities are unlimited: Remotely controlled uncouplers, flashing lights, sound functions, or whatever your fertile imagination can conceive.
To activate the function, press the corresponding function button on your remote or press the function button of the Train Mouse the corresponding number of times (e.g., eight times for function "8"). Function numbers are programmable via DIP switches.
The 55040 must be connected to 55020 MTS Loco Decoder. The 55040 cannot be used separately.

Faq No: 1006

Advantages of LGB "Onboard" MTS Decoders on Analog Layouts

Factory-installed onboard Multi-Train System decoders are generally invisible when operating the locomotive on an analog layout. That is, the loco operates like a traditional locomotive without decoders. But the decoder is there, and it does control the locomotive.

When operating on a digital Multi-Train System layout, the decoder controls the motor based on commands received from the Central Station. However, when operating on an analog layout, the decoder controls the motor based on the track voltage. This means that many of the decoder features work with analog operation as well.

For example:

Acceleration and Braking
Abrupt polarity reversals result in high stresses on the motor and gearbox of a conventional locomotive. The onboard decoders are programmed to avoid these stresses: The loco slows smoothly, but quickly, to a stop and then accelerates in the opposite direction.
With the onboard decoders, skidding wheels when entering a "Halt" block in front of a signal are a thing of the past. As track voltage goes to 0, the motor is electrically disconnected from the tracks and does not work as a braking "generator." Instead, its rotating mass acts as a small flywheel.

Programming decoder features
You can program many features of the onboard decoders - even for analog operation. To program the decoder, you need either a 55015 Universal Remote or a 55045 MTS PC Decoder Programming Module and a PC. (You also need a transformer with at least 2 amps output.)

To program your decoder, you change the function values in so-called registers or CVs. Here are some examples:

CV3: Acceleration
If you increase the function value in this CV, your train will accelerate slowly, even if you turn up the throttle abruptly. For example, imagine a train waiting at a signal. When the signal changes to "Go" and track power is restored, the train will accelerate slowly until it reaches the pre-set speed.
(Factory pre-set value: 3, range: 1-255)

CV4: Braking
Normally, the onboard decoder cannot control deceleration, that is, braking. If track voltage is switched off, there is no power to keep the motor running, and the train will stop immediately.
However, if track polarity is reversed abruptly, there is power, but with the wrong polarity. In this situation, the train will brake with the selected deceleration and then accelerate in the other direction. In CV58 (see below), you even can select how long the train will remain stopped before restarting.
(Factory pre-set value: 3, range: 1-255)

CV5: Maximum Speed
This value adjusts the speed of the loco at all voltages. This value is factory pre-set to the maximum value. Lower values allow you to match the drive characteristics of faster locomotives to slower ones. Then you can doublehead many locomotives with different gearboxes. Or slow down your locos so they don`t derail even at full speed on tight R1 curves.
If you usually run your locomotives at lower speeds, programming the maximum speed in CV5 allows you to use the full throttle range to control your locomotive. Also, a higher voltage is on the tracks even at low speeds, which increases reliability on dirty tracks. Finally, the lights are brighter at lower speeds.
(Factory pre-set value: 255, range: 1-255)
Hint: Before double-heading locomotives, test the locomotives to make sure they start at roughly the same voltage and move a similar speeds throughout the speed range. Reprogram the maximum speed to make a loco faster or slower. However, the starting speed cannot be adjusted for analog operation.

CV29: Direction of travel
You can reverse the direction of travel of your locomotive. For example, you can program one locomotive so it runs in the opposite direction of your other trains, all on the same track block.
However, CV29 can be programmed to allow only digital operation. If your loco doesn`t run, even though the power control switch is set to the right setting, this value may have been changed accidentally. Program this value to 4 for normal direction (factory pre-set value) or 5 for inverse direction. (Other values are possible, but should not be used for operation with LGB power supplies.)

CV49: Voltage for function terminal
You can adjust the voltage for the function terminal. Usually, the smoke generator of steam locomotives is connected to this terminal.
(Factory pre-set value: 5. Values: 5 for 5 volts, 26 for 19 volts, 32 for 24 volts)

CV50: Voltage for lights
You can adjust the brightness of your lights. For example, locos with old-style carbide lights can be dimmed so they are not as bright as those of newer locos with electric lighting.
(Factory pre-set value: 5. Values: 5 for 5 volts, 26 for 19 volts, 32 for 24 volts)

CV54: Back-EMF function with analog operation
If you set this function to "On," you get a "cruise control" function even with analog operation. This function will maintain a constant speed of the loco even if the resistance changes, for example on up- or downhills and in curves. The loco will run a little slower than before to have a "reserve" when resistance increases. Using CV60, CV61 and CV62, you can adjust this function to your personal preferences.
Back-EMF for analog operation is unique to LGB locomotives and decoders. Especially for automatic operation, the trains run a lot smoother with Back-EMF.
(Factory pre-set value: 2. Program to 6 to turn on analog Back-EMF.)
Hint: The Back-EMF function works only if your transformer provides enough power reserves for your train. We recommend LGB 50110/50111 transformers or LGB 50100/50101 JUMBO power packs.

CV58: Wait time
If the polarity of the track power is reversed abruptly, the loco will brake with the selected deceleration (CV4). After the programmed wait time has elapsed, the loco will accelerate with the selected acceleration (CV3) in the opposite direction.
With two 17100 EPL Track Contacts that switch a relay consisting of a 12010 EPL Switch Drive with attached 12070 EPL Supplementary Switch, you can reverse the polarity at the ends of a line to have the train shuttle back and forth.
(Factory pre-set value: 0, range: 0-255)

CV60: Back-EMF maximum adjustment factor
If analog Back-EMF is set to "on" in CV54, you can adjust the adjustment factor. This value should be selected so that changes in load do not cause oscillations in the loco`s speed. With a poorly selected value in CV61, you get a `heavy-handed" engineer who first accelerates until the train goes too fast, then brakes until it is too slow, etc., until the correct speed has been reached.
(Factory pre-set value: 10 [early locos with onboard decoder: 48], range: 0-255)

CV61: Back-EMF adjustment frequency
If analog Back-EMF is set to "on" in CV54, you can adjust the time between when the decoder realizes that the load has changed and when the adjustment is made. The effect is as if the engineer is daydreaming and takes a little time to adjust the train`s speed.
(Factory pre-set value: 5, range: 0-255)

CV62: Back-EMF maximum adjustment
If analog Back-EMF is set to "on" in CV54, you can adjust the maximum adjustment. For example, if your locomotive is not very powerful, it should slow down somewhat on steep hills - to achieve this, you can decrease the value of CV62.
(Factory pre-set value: 255, range: 0-255)

A few hints:
- If you own a PC, we recommend the 55045 MTS PC Decoder Programming Interface for programming decoders. It makes adjusting the CVs easy and convenient. You can read all the CVs of the loco decoders and select new values as desired.
- If you would like these features for older locomotives without onboard decoders, you can equip these locomotives with the 55021 and 55022 MTS loco decoders, which have most of these features.
- The factory pre-set "CV" values stated here may vary from loco to loco.

Products, specifications and availability dates are subject to change without notice. Some products are not available in all markets and at all retailers. Some products shown are pre-production prototypes. LGB, LGB of America, LEHMANN and the LGB TOYTRAIN logotype are registered trademarks of Ernst Paul Lehmann Patentwerk, Germany. Other trademarks are the property of their owners. © 2002 Ernst Paul Lehmann Patentwerk.

Faq No: 1188

After programming MTS decoders with my 55015, I can't control trains. Why?

After you have programmed decoders with your 55015 and a programming track (see No. 1097), unplug the programming insert. Wait at least 15 seconds before plugging in the insert for normal operations. Otherwise, the display on the 55015 will show "P --" and you cannot operate trains.

Faq No: 1120

Are LGB MTS decoders identical to Lenz decoders?

No. The very earliest LGB loco decoders were made by Lenz. However, all current decoders -- including onboard decoders -- are made to our specifications by another supplier.

Faq No: 1202

Can I program advanced functions on my MTS decoders?

Yes. LGB 55020 MTS Decoders have advanced functions. To program these functions, you need a 55015 Universal Remote and a programming track. You can program the following functions, depending on the type of decoder:

V2, V3 [in brackets: factory setting]:
Register 1: Loco address (00-22) [3]
Register 2: Voltage of first speed step (01-15) [01]
Register 3: Acceleration (01-15, 01 fast, 15 gradual) [01]
Register 4: Braking (01-15, 01 fast braking, 15 gradual) [01]
Register 5: [4]; 0: normal direction, no analog operation; 1 opposite direction, no analog operation; 4 normal direction, analog operation possible; 5 opposite direction, analog operation possible.
Register 6: System settings (should be 0 or 1, otherwise programming of other registers is blocked)

ME1-1 [in brackets: factory setting]:
Register 1: Loco address (0-22) [3]
Register 2: Voltage of first speed step (0-255) [3]
Register 3: Acceleration (0-255, 0 fast acceleration, 255 gradual) [3]
Register 4: Braking (0-255, 0 fast braking, 15 gradual) [3]
Register 5: max. speed (0-127) [127]
Additional functions can be programmed. See the 55020 instructions for details.

55025 MTS Switch Decoders and 55034 MTS Function Decoders have additional functions as well. See the instructions for the MTS components for details.

See also Nos. 1011, 1080 and 1111.

Faq No: 1113

Can third-party decoders be programmed using the MTS PC Decoder Programming Module?

It may be possible, if the manufacturer of a third-party decoder obeys the NMRA standards. However, few third-party decoders can handle the maximum voltage used with LGB MTS components.

Faq No: 1208

How can I install a non-LGB decoder in an LGB loco?

Unfortunately, we do not have detailed information on installing non-LGB decoders in LGB locos. There are many different LGB locos and many more different non-LGB decoders. So the number of possible combinations is extremely high. Also, we can never know when another maker might change their decoders or connections. So we recommend contacting the decoder manufacturer for installation information.

However, many LGB locos have a standardized "four-pin" connection at the gearbox which will let you easily identify the basic motor and power connections. You can use these connections for basic installation of a non-LGB decoder.

Also, some newer LGB locos have a "DCC interface" for use with an LGB 55027 MTS Loco Decoder III or third-party DCC decoder.

Of course, you install third-party decoders at your own risk, just as you would if you installed a third-party accessory in your car.

Faq No: 1121

How can I reset my decoder-equipped locomotive to the factory pre-set function values?

You can reset most CVs of your decoder-equipped locomotive (whether factory-installed, decoder on board, or retrofitted LGB 55021 decoders). This also resets the loco address.

With the 55015 Universal Remote, insert the programming insert. When the display shows "P --", press 6, 55, then the right arrow. Then press 5, 55 and the right arrow.

With the 55045 MTS PC Decoder Programming Module, you can reset the decoder parameters directly.

Hint: Earlier versions of the MTS-PC program used with the 55045 resulted in faulty re-programming of the decoder. If this occurs, download the latest version of the program at www.lgb.com or use a 55015 for resetting the decoder.

Faq No: 1213

How do I install decoders in locos with "Direct Decoder" interfaces?

Locos with a round sticker displaying the words "Direct Decoder" on the gearbox are prepared for decoder installation. The following are NOT complete instructions for decoder installation, but guidelines:
- Open the loco and access the circuit board.
- Cut off the four wires of the decoder (don`t unsolder).
- Plug the decoder onto the loco circuit board.
- Reset the DIP switches (see loco instructions).

ATTENTION! Disassembly and reassembly of LGB locomotives should be attempted only by people with at least a moderate degree of mechanical and electrical ability.

Faq No: 1079

How many decoders are needed for the 2x232 locos?

You need two MTS decoders, one for the loco and one for the tender. Both decoders should be plugged directly onto the circuit board. The DIP switches inside loco and tender must be switched to the off position. Functions include whistle (#1), bell (#2) and lights (#9). The smoke generator and sound are always on.

Faq No: 1152

How many lights and other accessories can I connect to LGB MTS decoders?

LGB Multi-Train System decoders are equipped with three terminals where you can connect lights and accessories: a terminal each for front light, rear light and function.

55021 MTS Loco Decoder II
You can connect up to 600mA (0.6A) per terminal, but no more than 1200mA (1.2A) total to all three terminals. This allows you to connect
- up to 10 LGB 24V light bulbs, or one LGB smoke generator to each terminal,
- but no more than 20 light bulbs, or 10 light bulbs and one smoke generator, may be operating at any time for the entire decoder.

(When the voltage is re-programmed to a lower value via CV49 and CV50, the allowable load decreases a bit because of the pulse nature of the current. But because LGB 5V light bulbs and smoke generators consume a little less power than the equivalent 24V accessories, you can use the same number of accessories.)

55022 MTS Small Loco Decoder
You can connect up to 100mA (0.1A) per terminal, but no more than 200mA (0.2A) total to all three terminals. This allows you to connect:
- one LGB 24V light bulb to each terminal,
- and up to three LGB 24V light bulbs total (1 per terminal).
- You cannot connect LGB smoke generators directly to the terminals of the 55022.

(When the voltage of the 55022 is re-programmed to a lower value via CV49 and CV50, the maximum output of each terminal is lowered to 40mA (0.04A). This allows you to connect one LGB 5V light bulb to each terminal.)

Attention! If the decoder terminals are overloaded, the decoder can be destroyed!

Current draw of LGB accessories:
- LGB 24V light bulbs: approximately 60mA (0.06A).
- LGB 5V light bulbs: approximately 40mA (0.04A).
- LGB smoke generators: approximately 600mA (0.6A).
- Older screw-mount LGB light bulbs (24V): approximately 100mA (0.1A).
- Accessories from other manufacturers vary in their current draw. Check the manufacturer`s information before connecting these accessories to LGB decoders.

Faq No: 1230

Is the "Type 2" MTS Central Station compatible with older MTS decoders?

Yes. The 55005 MTS Central Station, Type 2 (23 loco addresses) is completely compatible with older MTS decoders. This upgraded Central Station also is included in the 55105 MTS Starter Pack, Type 2.

Faq No: 1095

Is the track current limited when programming MTS decoders?

No. That is why a short circuit -- as can occur when a decoder is installed incorrectly -- will destroy the Universal Remote or other programming device. So locos with newly installed decoders should always be tested before programming.

Faq No: 1207

MTS: Advanced Functions of 55025 MTS Switch Decoders

In addition to being able to set the EPL drives of LGB switches, signals and uncouplers, the 55025 features several advanced functions: On/Off (with timed delay), synchronous flashing, asynchronous flashing, as well as the timing of these functions. All of these features can be programmed with the 55015 Universal Remote or with the 55045 MTS PC Decoder Programming Module. You can use these features to create custom controls for station lights, signals and other accessories. For more information on the advanced functions, see the instructions for the 55025 MTS Switch Decoder.

Faq No: 1011

MTS: Are LGB add-on decoders "p" compatible?

No. LGB add-on Multi-Train System decoders -- including the 55020, 55021 and 55022 -- cannot understand "p" or "parallel" function commands, because they have only one function terminal. However, because the command for parallel or serial function control is set individually for each loco address, locomotives with serial function triggering and those with parallel function triggering can be used together on layouts operated with "p"-compatible controls.

When a loco not compatible with "p" receives a parallel function command, it will not react. If your loco does not react to function commands, select that locomotive with your remote and press the "F" and "9" buttons to reset the function triggering for this loco address to serial.

Faq No: 1227

MTS: Can a loco with onboard decoder run on layouts operated with third-party digital components?

If the components are compatible with the NMRA DCC standard, then you probably can control the basic loco functions -- speed and direction -- on a layout with third-party components.

However, advanced loco functions -- like sounds -- may not function as expected. LGB onboard decoders are designed to accept both NMRA "parallel" function commands and MTS "serial" function commands (F1-F8) without reprogramming.

We do not recommend or support the use of third-party components, and the user of third-party components assumes the risk for any damage.

Search for "onboard" to find other entries on this topic.

Faq No: 1149

MTS: Can an MTS decoder be installed in my loco?

Most current LGB locos are equipped with integrated "onboard" Multi-Train System decoders. MTS decoders can also be installed in most other LGB locos, new or old.

Locos with Direct Decoder Interface
Identification: These locos also have a round sticker with the words "Direct Decoder" on the gearbox.

Do-It-Yourself Installation: If you have a moderate degree of mechanical and electrical ability, you can install decoders in these locos. A Decoder Interface Cable (55026) is not required.

Locos with Decoder Interface
Identification: These locos also have a round black sticker with six white dots on the gearbox.

Do-It-Yourself Installation: If you have a moderate degree of mechanical and electrical ability, you can install decoders in these locos. A Decoder Interface Cable (55026) is required in many installations.

"D" Gearbox Locos
Identification: These older locomotives have the letter "D" molded on the underside of the gearbox.

Do-It-Yourself Installation: If you have a high degree of mechanical and electrical ability, you may be able to install decoders in these locos yourself.

"Sandwich" Gearbox Locos
Identification: These older locomotives have a gearbox with a top plate, middle box and bottom plate.

Do-It-Yourself Installation: If you have a high degree of mechanical and electrical ability, you may be able to install decoders in these locos yourself.

"Shell" Gearbox Locos
Identification: These very old locomotives have a gearbox with a seam running lengthwise across the bottom.

Do-It-Yourself Installation: If you have a high degree of mechanical and electrical ability, you may be able to install decoders in these locos yourself.

Small Locos
Identification: These include handcars, "field railway" and propeller-driven locos.

Do-It-Yourself Installation: If you have a moderate degree of mechanical and electrical ability, you can install 55022 MTS Small Loco Decoders in these locos.

Track Cleaning Locos
Identification: These are the 2067 and 20670 Track Cleaning Locomotives.
F
Do-It-Yourself Installation: Read the loco instructions for special information. For older track cleaning locos (made before 3/98), we strongly recommend professional installation of decoders.

Faq No: 1013

MTS: Can locomotives with onboard decoders run on analog layouts?

Yes. No modifications are necessary to run the loco on either an analog or a Multi-Train System layout. In fact, all MTS decoders -- onboard and add-on -- are engineered to automatically switch between digital and analog operation.

Search for "onboard" to find other answers about onboard decoders.

Faq No: 1146

MTS: Can third-party decoders be installed in locos with onboard decoders?

Installation of a third-party decoder may require removal of the main circuit board and the loss of all functions -- light control, voltage regulation, sound and so on -- provided by the main circuit board. As always, we do not recommend or support the use of third-party components, and the user of third-party components assumes the risk for any damage.

Search for "onboard" to find other answers about onboard decoders.

Faq No: 1148

MTS: Is the on-board decoder programmable?

Yes. Advanced users can program many features, including individual speed steps, output voltage for motor, lights and functions, acceleration and braking, starting voltage and many other functions. However, all this is optional. The consumer only needs to program the loco address. Everything else is factory-preset and does not need to be changed.

Search for "onboard" to find other answers about onboard decoders.

Faq No: 1150

MTS: What is an "onboard" decoder?

An onboard decoder is a LGB Multi-Train System decoder integrated into the main locomotive circuit board. The traditional, "add-on" decoder is a separate circuit board that must be installed in the loco.
So if you have an analog layout, the onboard decoder is invisible. When the decoder senses analog power, it automatically switches to analog operation. So the user can go to a friend's layout -- no matter whether it is analog or MTS digital -- and run the loco.
But if you decide to convert to digital operations at a later date, it will be easy: Just get an MTS Central Station and a remote, and you'll be ready to have fun with the Multi-Train System.
If you already have an MTS layout, the onboard decoder eliminates costs of decoder installation. Plus it eliminates installation hassles and preserves the LGB warranty.

Search for "onboard" to find other answers about onboard decoders.

Faq No: 1144

Some of my 55020 MTS decoders look different than others. What is the difference?

LGB continuously improve their product line. This includes the MTS Decoders. The main functions of all 55020 decoders are the same. However, there are some slight differences:
- V1 (labeled "LGBE1_V1," rare, only few made): Don`t connect smoke generator directly to the function pins, but use relay as shown in instructions.
- V2 (labeled "LGBE1_V2"): Connect smoke generator directly to function pins (no matter what the instructions say).
- V3 (labeled "LGBE1_V3"): Same as V2, but using different electronic components.
- ME1-1 (no "V" number, sticker with a serial number): Same as V3, but advanced functions can be programmed.
Hint: Sometimes the decoders were updated before the instructions were changed. If you have a "ME1-1" decoder with instructions that do not mention the advanced functions, you can download the current instructions at www.lgb.com

Hint: The new 55021 MTS Loco Decoders II have additional features, but the connections are the same as for the 55020.

Attention! Do not mix decoder types on the same (two-motor) locomotive.

Faq No: 1080

The MTS loco decoder instructions say that I can choose 14 or 28 drive steps. How many does the MTS actually use?

To maintain compatibility with the original "LGB/Lenz" MTS components, the MTS uses 14 drive steps. However, because of the relatively large mass and inertia of most LGB locos, the number of drive steps is not as crucial as it is with smaller scale. The 28-step option is offered for compatibility with other DCC systems only. It cannot be used with the MTS.
Also, the apparent number of drive steps can be increased through interpolation by the loco decoder to 256. If CV3 and CV4 (acceleration and braking) are adjusted appropriately, the decoder has enough time, when the drive step setting is changed, to execute every one of those 256 steps. The result is extremely smooth operation.

Faq No: 1201

What are decoder registers?

In the registers -- sometimes called CVs -- you can program various "function values" which determine the characteristics of your decoder, including the address and advanced functions.

Faq No: 1134

Where do I find instructions for installing MTS decoders and setting the DIP switches in the loco?

Very basic instructions are included with the 55020 MTS Decoder. However, we strongly recommend professional installation of decoders. There are a multitude of mechanical and electronic issues to deal with.

BUT if you are mechanically and electronically inclined, you can do many decoder installations yourself...

- The DIP switch settings are given in the instructions for many locomotives. For example, look for a "Hint" that says something like: "If this model is equipped with a decoder, the digital/analog DIP switches on the loco circuit board must be set to OFF. The DIP switches should remain in this setting, even if the model is used on an analog layout."

- There have been many articles in LGB Telegram magazine concerning specific decoder installations.
- For recent locos with "decoder interfaces" the electrical installation is relatively easy, but the mechanical issues -- disassembly and RE-assembly -- can be far more troublesome. Use the "Service" parts diagrams as a guide. They are available for many locos in the Manuals button on our site,

Faq No: 1130

Which LGB locos have integrated "onboard" MTS decoders?

Most current production LGB locos are equipped with "onboard" MTS decoders. These locos are clearly marked with a silver "Analog + Digital" sticker on the loco packaging and with the "Analog + Digital" pictograph in our online Product Library.

Also, some current production LGB locos are equipped with a "DCC Decoder Interface" and can be equipped with third-party DCC decoders.

Faq No: 1214

Frequently Asked Questions

MTS Decoders FAQs