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Control Märklin transfer taible without modification with switching decoder

This manual show how you can use the Märklin transfer taible in Rocrail with a simple switching decoder manually and also in automatic mode. You can use this for a turntable too, but then you need feedback sensors at every (used) track of the turntable.

Different decoder have different port connections. Connect your decoder everytime as shown in the manual of your decoder! Please do the same with the power supply.

In this example I used the Tams SD-34 switching decoder.

Wireing shown in one picture:

Connectors 1-3 (Port 2) of the SD-34 are used for the driving direction. If you use a driving transformer, you can regulate the speed of transfering the bridge. This is necessary if your transfer table likes to overdrive stop points. Particulary transfer taibles with changed motors are affected by it.

  • Therefor connectors 1 and 3 have to be connected with blocking diodes to connector "B" of the Märklin transormer as shown in the picture.
  • From transformer connector "0" to transfer taible motor connector "M1".
  • Decoder connector 2 has to be connected with decoder conector 12.

Instead of transformer Connector "B" you can use connector "L". However then without possibility to regulate the transfer speed.

Port 1 of the decoder (Connectors 10-12) is used to start the motor.

  • Therefor connector 12 has to be connected to "M2" at the transfer taible.
  • Connector 11 to ground connection of the tt-motor.
  • Connector 10 is not used.
  • Connector "B1" of the transfer taible has to be connected with digital plus (Märklin middle power line).

If you want to realize digitalisation without modifications, you can use a current watch feeback between "B1" and the power line.
CAUTION: Do not use a feedback sensor modul which switch to gound connection!

  • Connect "B2" and "0" to your tracks (digital ground connection).

This construction realize to use the connectors for catenary from each track of the transfer taible for feedback. This connectors can be connected to a ground connection feedback sensor modul. For the 2 opposite tracks 0 & 24 you´ll need only one feedback signal.

Important: Witout modification, the transfer taible will connect every track with power. If you connect every track itself and use more than one booster circuit, you have to note this!

Hint: Instead of Port 2 & 1 you can also use Port 4 & 3. Significant is the correct assignment for direction and motorstart. Other ports needs different digital adresses.

Setup in Rocrail

After the transfer taible is added and a identifier name is given, the interface is the next step. Decodertyp is "accdec"

In this example the decoder has adresse 205. adress 1 is accordingly 817 and the adress 2 is 818.

Important: With decodertype "AccDec" it can be necessary to use different adresses. Please have a look in the central window and compare with real sent adresses.

Example with decoderadresse 205: If instead of 817 a 409 and instead of 818 a 410 is transmitted, you´ll have to set adress 1 to 1632, and second adress to 1634 like shown in the picture. In this case correct values with other Ports oder decoder adresses have to be find out seperately, based to the sent adresses. A benchark is round about twice as high.

Field feedback sensor 1 is the feedback of bridge occupation. The example shows 2 sensors, cause my bridge is modified with 2 photoelectric barriers.


Last specific configuration are the tracks. The Märklin transfer taible only has 2 opposite tracks and the rest is offset. To realize a possible best presentation and that all tracks will be reached correct, a special order of tracknumbers is needed. In Rocrail the transfer taible is based on a turn table. Through this the Rocrail trac 0 is opposite of Rocrail trac 24, etc… This results in following assignment: left side contains tracks 0, 1, 3, 5 7, and right side contains 24, 26, 28, 30, 31.

There are some more arrangements, but then no clear order of numbers is possible.

Only visual a bit unattractive, the bridge at position track 32 can´t be presented, cause it is outside the transfer taible. It would be possible to present at last position, but then the turn taible will not move to track 7, or to all other tracks.

Track 0 and 24 are listed seperate, so you can assign different blocks. Both tracks can be choosen and both will drive the bridge to upper position.

The transfer taible is configurated - don´t forget the driveways.

Hint: Have a look at a uniformly + and - arrangement of your blocks. This make it easier to create driveways. If a loco left bridge at the wrong side, you should check if + and - is set correct in driveways.

Hint: Due to design of the transfer taible the connectors of the bridge and tracks can let start the loco, before the bridge has stoped. Enter a value higher than 0 at „Delay“ within Interface options of the transfer taible. 1 second should be enough.

If driveways start the transfer taible, sometimes when a loco has arrived it take a few seconds to start the transfer. Track before will drive downside (numbers counting up), next track will do opposite.

Known problems during configuration: Some changes in Rocrail interface can cause, that the doubling effect of needed adresses will occur. I don´t was able to find out what causes this and it seems impossible to make undone. In this case use a backup workstation.

userpages/mikeh/msb-en.txt · Last modified: 2022/05/17 22:48 by mikeh