Living on the continent – in “Europe” as our British friends would say – the UK remains as exotic as the US in terms of rolling stock. German manufacturers tend to ignore UK trains, but while in London I was reminded how different EMUs and DMUs are on the other side of the Channel.
Here is a DCC conversion of the Dapol Class 156 DMU, with sound and interior lighting.

Dapol ND-112A - Northern Rail Class 156

Dapol ND-112A – Northern Rail Class 156

The model

What strikes me in this unit (Dapol part no ND-112A), is that it actually looks like passenger cars. The driving cabin is on the side, so that the car can still be connected to another unit while letting passengers go through. It is not as elegant as some recent UK trains or continental DMUs, but it’s original.
The Dapol Class 156 comes with a motorized and a dummy unit.

Opening a model from a manufacturer you don’t know is always interesting. I must say I was rather impressed by the apparent quality. It seems I must stop only trusting models from the ex-Axis (Germany & Japan) 🙂 It deserved both sound and interior lighting add-ons.

All 8 wheels are feeding the car with track power, and red/white front headlights are present, with a NEM 651 plug. There is a separate connector for a “light bar” next to the NEM 651 plug. As explained in the manual, this is to be connected to an interior lighting board. I thought this was great, but as said in multiple online forums (e.g. here) the light bars are directly connected to the tracks, not to the DCC decoder. That means neither on/off function, nor flickering protection. That won’t be good for me so I will bypass this light bar connector.

The dummy unit is made on the exact same basis as the motor car, this is quite obvious as the wheels have gears (that run free) in the bogies. Headlights, NEM 651, the interior is exactly the same, just without a motor.

The only weak point is the coupling system. The attached coupling mechanism is an old “hook” system, that requires manual intervention for coupling/uncoupling. Not only that, but there is no “short coupling” mechanism: the hook is attached directly to the bogie. Dapol does deliver a shorter “hook” that can replace the default one. But without a proper short coupling mechanism, as they say in the manual, this will only work if you have large curves. If you were to replace the coupling, Dapol also includes 2 new  & thinner “accordions” sections (the piece allowing passengers to move between cars).

Converting the dummy unit

Decoder install disclaimer:

I am a hobbyist, my installs are for information only, as I am still "learning by doing". If you are afraid to damage your vehicle, or expensive DCC decoders, leave your DCC conversions to a professional Model Railroad expert!

I decided to fit this unit with a cheap LED-board (part no. 246880 at Conrad): at €2,90 per board, I can live with only 3 LEDs.
My best choice as an accessory decoder is the FD-R Basic from Tams Elektronik (part no. 246917 at Conrad). It has 2 function outputs, and also is Railcom-compatible. In the case of a car with 2 headlights and interior lighting, I would really need 3 outputs; but the FD-R costs less than €11 and is very very small.
As for the NEM 651 plug (which the FD-R doesn’t have), I didn’t want to touch the interface from the Dapol, although there are soldering points for people who want to bypass the NEM interface. So I used a Lenz NEM 651 board (part no. 80015) and soldered the outputs of the FD-R to it.

Below is a drawing of the installation I did. This is a classic setup but here is a summary just in case, with Conrad part no.:

  • The FD-R supports an added capacitor to avoid flickering, I added one of 220uF  (445477)
  • With 2 functions only (both used for rear and front lights already on board the car), the interior lighting board will be connected to Aux 1 & 2 (front & rear light outputs), to be on no matter in which direction the engine is running. Since those 2 outputs also are connected to the actual front & rear lights – via the NEM 651 interface –  we need 2 diodes to avoid a power loopback and keep those turning on discretely (2x 162280)
  • We need a resistor, the LED board has none (e.g. 404047)
Tams Elektronik FD-R Basic DCC, interior lighting led board (in Dapol Class 156 DMU) on NEM651 plug

Tams Elektronik FD-R Basic decoder used to power
interior lighting (led board) and front/rear lights (via NEM plug)

Here is a quick picture of the LED board (resistor and diodes on the left), with the decoder (on the right), connected to the on-board NEM651 plug:

Dapol ND-112A Dummy with led board and Tams FD-R Basic

Dapol ND-112A Dummy with led board and Tams FD-R Basic

Converting the motor car

I will install my usual decoder, an ESU Loksound Micro v4.0. It comes with cables on a NEM651, so basic installation will be easy. I will add a small round speaker also from ESU (part no 50328), it is not very powerful so purists will prefer a better speaker.

As for the interior lighting, I will be using the same one as for the dummy car. The Loksound already has soldered cables for 2 auxiliary outputs, and the common (+) pole. Connection will be easy (I’ll just need to add a resistor), and I even have an extra unused AUX output.

ESU Loksound Micro v4.0 & Dapol ND-112A

ESU Loksound Micro v4.0 & Dapol ND-112A

What I like about this Dapol model is that motor and transmission are fully under the interior furniture plastic piece. Not only does this look better, there is also no risk to block the motor with cables or glue.
As usual, I take a conservative approach to modifying my trains. I want to limit my modifications as much as possible. For this reason, I will install the Loksound without changing the cable length or removing the NEM 651 plug. The decoder fits well under the roof, in the middle of the car; I just added a very small dose of hot glue:

Loksound Micro v4.0, led board on Dapol DMU

Loksound Micro v4.0 and led board with added resistor

As for the LED board, it was easy to connect thanks to the cables of the Loksound:

Loksound Micro v4.0, led board

Loksound Micro v4.0 connection to led board (with added resistor)

Placing the board was more of a problem, well the easiest solution was to stick it on the decoder. The sound decoder itself is quite thick (about 4mm), so that means the LED board will sit quite low in the car once the roof back in place. Luckily, it still sits high enough not to be visible from outside. As for the speaker, it fitted perfectly in the front of the car (the side that will be coupled with the dummy):

Dapol ND-112A, ESU Loksound Micro v4.0, led board

Dapol ND-112A with ESU Loksound Micro v4.0 and led board

Since the motor is on the floor, I couldn’t make a hole at the bottom of the car for the sound to be heard. I also didn’t want to remove a windows or two on the sides (too obvious). So I removed the window from the “accordion”, on the side that will be (most of the time) coupled with the dummy car.

Suppression de la fenêtre de l'espace inter-wagon.

Programming the decoders

In the dummy, I programmed the Tams decoder with my ESU ECOS II. Unfortunately, the LED board isn’t enough of a load for the decoder to “confirm” CV changes to the central station. It works, but the command station shows an error as it receives no confirmation. Remember in classic DCC programming, the decoder sends a  confirmation by simply consuming a given amount of power: this is why trains with motors “hop” during programming. I gave the dummy a different address than the main car, just in case I want to control the lights separately.

As for the power car, I used my ESU Lokprogrammer and its software. I couldn’t find any “sound project” to download on the ESU website (in fact, there is not a single UK sound project available!). I am not a purist, so I picked up a sound project from a Belgian DMU that seemed to sound right. All functions where programmed as usual, and I mapped the AUX 1 output (interior lighting LED board) so it remains on along with the headlights (F0).


Dapol has given me a good first impression. If you forget the old fashioned coupling system, this railcar really looks and runs good, even at small speeds. Although I don’t really mind an extra millimeter between cars, not being able to uncouple the cars with a standard track uncoupler is a disadvantage.

Adding sound and lighting was (for once) not too complicated, so I’ll definitely be running this DMU in a very unrealistic fashion: along with my French or German rolling stock. Below is a last picture (please note a yellow accessory that goes on the front hasn’t been attached yet).

Dapol ND-112A, ESU Loksound Micro v4.0, Tams FD-R Basic Railcom

Dapol ND-112A with Loksound Pilot Micro v4.0 in motor car, and Tams FD-R Basic in dummy car; both with led boards for int. lighting

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