Hi,

Last evening I was running some trains in my layout. After some minutes I heard one of the transformers making
that "ding" sound when there is a short some where. A quick glanse around the track... and WHAT??? Smoke rising
from 4078 "Kakadu" restaurant/luggage wagon at the station. Quickly power off and I pulled wagons with loco towards me.
I took the smoking Kakadu to side and started to investigate what has happened. The tin body was warm nearly hot!
I took the roof away and the smell was terrible. Led bulb had gone short and melted the light diffusor, burned the white
cardboard to brown and made a black burn mark inside the roof.

I have had problem with these led bulbs before. Two have just made a snapping sound and went dead but never something like that!



Let's be careful out there

Åke

Edited by user 08 January 2016 10:34:31(UTC)  | Reason: Edited wrong item number

They are for 16-22V and my layout is analog. Power supply is white 32VA Märklin transformer 6647.

Best regards

Åke

Yes, but there is a single LED per bulb, and for 16-22V supply there will be a reasonable size resistor in there, or the resistor is too low a value and the LEDs are running at excessive current. This is where the modern 'LED strip' is much better as the dissipation is distributed.

I am a little confused. The 4087 is a TEE Restaurant coach. It is not a Kakadu, nor is it a luggage coach. The coach is equipped with a seating area and a kitchen. The kitchen has an access door which you might have misinterpreted as a luggage area. Or did you mistakenly write 4087 instead of 4078?
WRmz132 4087: https://az95169.vo.msecn.../images/marklin/4087.jpg
The Kakadu (ARm) 4078: https://www.marklin-user...cs/rayf/4078%20-%201.JPG

Are the LED bulbs made by Maerklin or approved by Maerklin? I have had at least one occasion where a bulb overheated and melted the light channel. Fortunately, it was discovered before the heat did any damage to the plastic coach shell.

I am glad that the damage was primarily limited to the light channel. You should be able to find a replacement. Have you considered replacing the original lights with a LED strip that you could attach to the inside of the roof with two sided tape. this might be a better solution that using a LED in the socket designed for the original bulbs.

Regards

Mike C

Thanks for the warning! I have installed them in some of my coaches, but I do not really like them, as the light they emit has a greenish colour. I bought them from Conrad.
Do they get hot during normal use, or only if they malfunction (internal shortcut or something similar)?

I can't check right now because my layout is covered in plastic. I am redoing my layout room.... Haven't run my trains since October...
Gregor

Hello/Terve!
Must pay attention to this maximum LED current. You can measure the LED current(20mA typ) in the normal operating voltage. If the current is approximately 20mA, then put in addition to a series resistor. 1kOhm/0,25W probaly suffice. The power need not be exatly 20mA, may be less, when only the light going to.
www.veturitalli.fi and www.rautatieasema.org -pages of these stories. Also the interior light flicker.


se on moro vaan

ealab

Edited by user 16 January 2016 20:37:49(UTC)  | Reason: Not specified