Conversion parts:
For the 28502 I used the mfx conversion kit 60921.
Updated 15.06.2009
Märklin 28502, RCT 36 274:
Conversion parts:
For the 28502 I used the mfx conversion kit 60921.
Decoder:
The decoder is installed at the same place as the original Delta decoder. It is installed in the holder
456200.
The mfx decoder in 28502:
Motor:
Installation of the motor itself is not very difficult, but requires some
mechanical work in the locomotives with two light bulbs. After removing
all the existing parts (motors, delta decoder, bulbs etc.), clean the chassis
and make sure that everything (transmission and wheels etc.) is turning
smoothly. Before installing the new motor:
The top of the motor cover (brush holder) is a little bit lower than the top
of the magnetic field part of the motor. In the V36 locomotives with two
light bulbs in the center, the light guide leading to the rear lamps will hit
the magnetic field part, as it is wider than the similar part for the old motor.
The four metal plates making this width difference must be filed or grinded
down to the same height as the motor cover to give space for the rear light
guide. It is best to remove the field top from the magnet. It is difficult to
get rid of all the filing dust sticking to the strong magnet. Leave the
magnet on the lower part of the magnetic field, to make sure it is installed the
correct way. If installed the wrong way the motor will rotate the wrong
way. If so, the blue and green wires to the brushes must be swapped.
Hold the magnetic field metal plates tight together with a vice or pliers when
working on them. Otherwise small metal particles may be forced down
between the metal plates, making the part
too thick. Be careful with the guide pins. Be sure that all filing
dust is removed. I normally rinse the part with hot water and dry it carefully.
The modification can be seen in the below photo.
Install the new motor to the locomotive, firstly without the brushes. Check once more that everything revolves effortless. Install the brushes.
The motor in 28502:
Lamps:
The original lamps holders in the locomotive is used, now with 610080 bulbs.
The interior light are two 610080 bulbs connected in series. A small
mono-stable relay is installed for light power supply to the connected cars.
Wire connections:
| Wire colour | function | Connecting to |
|---|---|---|
| Red | B (center contacts) | pick-up shoe connector and relay switch |
| Brown | 0 (tracks) | locomotive ground |
| Blue | Motor brush | rear brush holder |
| Green | Motor brush | front brush holder |
| Orange | Common + | bulbs, in total four (front lamps and interior light) and relay coil |
| Grey | Forward lights | front lamp holder (decoder side) |
| Yellow | Reverse light | rear lamp holder (motor side) |
| Brown/red | function 1 | relay coil, for power supply to connected cars |
| Brown/green | function 2 | interior light, two 610080 in series |
My setting of the decoder:
| Decoder settings, 28502 | Default | Mine | ||
|---|---|---|---|---|
| Analog settings: | ||||
| Enable analog mode | check | < | ||
| Starting voltage | 7,300 | < | ||
| Maximum voltage | 23,000 | < | ||
| Control settings : | ||||
| Swap directions | uncheck | < | ||
| Max speed | 255 | 77 | ||
| Min speed | 4,000 | < | ||
| Acc time | 7,000 | 10,000 | ||
| Dec. time | 3,750 | 10,000 | ||
| Forward trim | 1,000 | < | ||
| Reverse trim | 1,000 | < | ||
| Motor settings: | ||||
| Motor PWM-frequency: | ||||
| Low frequency | uncheck | < | ||
| High frequency | check | < | ||
| Load Control | ||||
| Reference parameter | 11,300 | < | ||
| Control parameter K | 60 | < | ||
| Control parameter I | 120 | < | ||
| Control influence | 255 | < | ||
| Special options: | ||||
| Preserve direction | check | < | ||
| Persistent acceleration | uncheck | < | ||
| Persistent speed | check | < | ||
| Persistent functions | check | < | ||
An x-ray shot of my 28502:
