Hi everyone,

I am aiming to use a function decoder in order to control interior passenger car lighting. The load on a set of passenger cars. (LED, current conducting couplers, each car with its own ground spring/return) is too many milliamps for the function decoder to supply on its own.

The good solution for this to use a relay, which simply turns the power to the current conducting couplers "on" and "off"

I have procured ESU relays, number 51963, to do this: https://www.esu.eu/en/pr...sories/miniature-relays/

My challenge: in case of momentary power interruption, the relay will unlatch and need to be re-activated via the function decoder to turn the lights on again.

So my question: I'd like to use a capacitor to buffer against this, but don't know where to wire it in line? Would I be correct in placing it between the decoder function outputs and the relay? Meaning: F1 output - Capacitor - Relay - Lighting (via current conducting couplers)

Thanks in advance! In theory this works the same for any decoder, but the subject in question is an old marklin accessory decoder number 60960

Did exactly the same in my coaches
The relay however is in my lok's and turned on/off via F1 from the lok decoder, "main power" to the relay comes from the pickup slider of the lok
As you found out, no need for a cap on the relay, the cap on the LED strips keep the lights on even when the relay opens up intermittent....

Regards
Jean-Pierre

Thanks for this thread John (5HorizonsRR).

I have a decoder (used in Marklin ALCO PA) that powers the lok for movement and also for the sound. However, the decoder is slightly malfunctioning and allows sound on all the time when the lok address is used. Function F1 - does not work and the locomotive running diesel sound is on all the time. Can be annoying.

I need a relay that will allow current to pass to the speaker and also to disconnect current to the speaker. I can cut one of the speaker wire that connects from the speaker and to the decoder. I can then connect the 2 cut ends of the wire (white here) to this relay. All I want is to allow/not allow current to go the speaker. How would I solder the 2 wires (one from the decoder, and one from the speaker).

Since this is an ESU relay, I have a spare ESU 60760 decoder to use for this.

Thanks.

One note if it helps, as I've now done my second set and found a few details of note:

- Marklin decoders use ~12v for the functions (typically, I'm not sure about all Marklin decoders)
- The ESU relay is designed for 12-16v, so you should be fine if using a Marklin decoder.

- Some NEM DCC decoder function outputs are 5v- which might make for a slow and noisy ESU relay. (they do still work though- which surprised me)
- Your ESU 60760 decoder might be putting out 5v per the NEM standard, creating the (minor) issue above. Something to check, or get a lower voltage relay for.

I am working through this challenge myself, the subject of another forum thread. Perhaps a 5.5v coin capacitor will buffer the relay and then you will only have the noise at initial startup. Or you can use a lower voltage relay.

I'll report back once I've made more progress on this....

Edited by user 04 March 2025 18:51:12(UTC)  | Reason: Not specified

With the MS or CS, you can select for each function whether it is a momentary (when pushed), duration or switch operation, so you can toot a horn, sound a long blast or trip a switch (lights on).
When you are running a consist with lights/function via a decoder, normally you run wires from the decoder, so you are no longer using ground or live from each car/coach. For this type of setup, a two or multi-pole coupling allows you to provide power for lights and functions.
A multi-pole allows you to have control of lights on/off and also have elements like tail lights or special feature controlled separately.

@Bill, I am pretty certain you wired something incorrectly. You should be able to have sounds and operation separately. The outputs from the motor connections and the speaker connections should be separate and you should make sure that you are not using a common ground.
You should make sure that the speaker circuit is connected to the proper outputs. You should also check because some decoders may have settings allowing you to select operation in analog mode, where the sound would be on all the time and your decoder might think that this was the setting in digital use too.

Both you and 5Horizons have good questions that can possibly be asked to digital(at)marklin.com to see what Curtis and Rick have to say.

Regards

Mike C