Welcome Udo.
I am not sure the location but someone will tell you within 24 Hours the conversion kit that you need. On the Marklin.de web page there is a table listing the conversions. Why not go for the ESU MFX Decoder???
Welcome to the Forum
Nev

Dear DT,

I think there is a misunderstanding. The old crocodile 3015, was manufactured from 1965 to 1975. There is neither a conversion kit nor a Hamo magnet existing. The motor is the largest flat collector motor, Märklin has ever built for a H0 locomotive.

If you want to convert the motor to DC, you have to cut the stator lamination and to put a magnet into the gap as realized in the controlled high-efficiency propulsion.

I also have a 30159, and still wonder why I did not get the 36159 instead...

As you say, this is the biggest LFCM motor produced and there are no kits to replace it. In analog, this motor is a real power-sucker - when I put this on the track and started it on my sons analog layout some years ago, all other locos suddenly went much slower, so it is a real current consuming motor indeed.

A conversion with neodym or alnico magnets indeed seems like the only possible way, but what I worry about is the fact that this motor is so huge and current consuming that a LokPilot decoder might go up in smoke as soon as you reach speedstep 2 or so...

Since I have not done it, I cannot recommend how many/how powerful magnet(s) to put there... The problem is what would be the optimal for the huge 3-pole anchor/rotor, and how do you measure that? One way is of course to use thin powerful magnets and empirically measure the rough optimal values regarding performance vs current draw as good as poosible, but you will never get the exact "optimal value"...

I fully understand your question, and the problem, but have no answer... I would be very interested myself in a solution for this specific loco... I have a bunch of magnets bought especially for this type of stator conversion, some are real powerful alnico or neodym magnets, some are plain ferrite as used in Hamo stators, some thin and some "fatter" regarding size... But I haven't made a single conversion with them yet...

The motor is really big, and if anyone has a picture of it - please feel free to post it here. Otherwise, I'll have to go to my storage location and dig up the 30159 so you can see what we are talking about...

Hi Juhan,

I know a person from another forum, who made the conversion with the biggest Hamo magnet and an ESU lokpilot successfully. But I don´t know how he installed the magnet, because the Hamo magnet includes the stator lamination and the ID is not equal to the 3015 stator.

He told me that the motor runs very smoothly and the decoder does not overheat and switch off. Nevertheless there is also the Zimo MX64H decoder which can provide a current up to 1.8A and this should be more than enough for this motor.

I guess that the current will also decrease using the permanent magnet. In a first step I would compare to the controlled high-efficiency propulsion from Maerklin. I would select a neodym magnet with the same cross section as the stator lamination. For the thickness I would select 2 or 3mm.

Hi,

You may also consider to use a decoder for AC motor, such as Uhlenbrok 76200.
It gives excellent results with standard 3 poles Marklin AC motors without any modification of the motor, and may be worth trying in your case.

Fred

Hallo,

a lopi didn´t go up in smoke because the motor outputs are current limited and temperature controlled. If you teke a permanent magnet instead of the coil, the current will decrease considerably.

The results with an Uhlenbrock 76200 are not good. It´s not possible to have a good load regulation without having a permanent magnet and e.m.f.