LEDs in Märklin System
Since Märklin is an AC system (3 rail), some unique characteristics of LEDs have to be kept in mind when using them. This is because LEDs are polarity sensitive. LEDs can replace the bulbs in Switches/Turnouts/Points and can be used in various other locations.
Traditional incandescent bulbs get hot and use much more electricity than LEDs. For example, an LED has a life expectancy of 50,000 hours versus 10,000 of a good bulb. In our effort to help customers get what they want and also to be more "Green", we introduced LEDs that can replace bulbs.
At present we have three types of LED products that can be used in train cars.
- E5 with older threaded/screw-type sockets
- C5 for turnout motors and similar (flange based) sockets
- S12 LED strips for passenger cars, in buildings, background, under layout and the flexible ones in tunnels etc.
Others types that we have, can be used in place of headlights, elsewhere in the locomotive or at the end of train as well. All LEDs are polarity sensitive and care should be taken in connecting them to the power. We also have mini rectifiers that can be introduced in-line to control polarity.
All LEDs except the C5 & CR5 are suitable for Märklin
voltage/power, as E5 and the S12 trips have the correct resistances
built in. The C5 and CR5 do not have any room inside the body for a
mini resistance to be incorporated. Hence they are sold with the
appropriate resistances in the package for adding externally in the
positive polarity feed. C5, CR5 and all our LEDs are available in our Shop.
Replacing Bulbs with LEDs in older turnouts/switches/points/
Click on images for an enlarged view.
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An older Turnout mechanism in Märklin K track. |
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Opened view of the turnout mechanism showing the incandescent bulbs which came as standard. |
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The older bulbs had a "flange" type base. As the size is small, the term used for this is "mini flange" base. Note that the bottom terminal is connected to the positive "yellow" wire. These also come in reverse polarity version called CR5. In the reverse polarity version the bottom is negative and the sides are positive. |
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The bulb is replaced with the C5 type LED, with normal polarity. But it cannot be powered up as such. |
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A resistor is needed to control the power to the C5 LEDs. A suitable one is 620R, which should be placed in-line as indicated. It would be easier to place it outside the mechanism. The C5 LED, does not come with a suitable resistance built in for use with voltage such as in the Marklin system, as in the case of E5. |
Alternate Solution ![]() |
To avoid the additional step of adding a resistance, an E5 type LED can be used. This is also suitable for light sockets in older passenger cars & comes in various colors, as shown in the LED section. Picture below shows an E5 type LED in place and also lighted up. It is tight enough and does not move easily. |
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Since the LED has a screw-thread base, and has no flange to snap into the socket, there is a possibility that it may loosen. Even though the cover of the mechanism keeps it pressed in place, a folded piece of paper may be placed between the LED and the cover, to additionally secure the LED. For clarity in photograph, we have used a "yellow" colored LED for this demonstration. |






