I would like to convert and upgrade my Marklin locomotives to digital. Why do I have to change the motor, and what are the options?
Older Marklin locomotives have AC ( Alternating Current) motors. You can recognize them by the electromagnetic spool on the side of the motor.
You will also see a reverse relay mounted in the locomotive. This reverse relay is activated when you push the speedknob on the transformer counter clockwise against the springloaded stop.
Digital locomotives receive AC power from the track, but the digital decoder “converts” that to DC power, to feed the motor. Thus the old AC motor will no longer work, a DC motor is needed to connect to the digital decoder. Luckily, the old AC motor can be converted to DC.
Converting the motor is relatively easy. You exchange the electro magnet for a permanent magnet, and also remove the reverse relay, as it is no longer needed.
In the most basic conversion you only change the magnet. Both Marklin and Esu offer them, and we stock them. Esu also has decoder sets with the magnet already included. There are three different motor types (DCM, SFCM, LFCM) and three different magnets, we explain that in another post.
Your second option is to upgrade the motor. In an upgrade, you not only convert the motor to DC, you also exchange the armature from 3- pole to a 5-pole. This improves running characteristics of the motor. Marklin offers upgrade kits for this purpose. Most people who convert their locomotives to digital end up upgrading the motor to a 5-pole motor.
After installing the upgrade kit, an upgraded Marklin 5-pole motor will look like this. The electro magnetic spool is no longer there. The permanent magnet does not need it. The green things that look like resistors are actually inductors.
