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Hello all,

I am about to embark on DCC, and so wish to chip some locomotives. I have read good reviews of the newer TCS M1 decoder with BEMF and also the DCX74 series decoders by CT Elektronik. My question is this - half of my models have NEM651 sockets so a DCX74 can be plugged straight in - no problem! However for hard wiring in on non-socketed locos I could use a DCX74 with wire interface or TCS M1 I understand, but the TCS M1 has seven wires instead of six. What is the extra wire (blue) for? I gather it is some kind of common positive for lighting? Is this only needed on American models because European ones are usually designed differently?

e.g. (Both models have built in directional lighting, green blobs are cuts to tracks)


Pictures from: http://leksicom.co.uk/

So no blue wire (see below) needed? Can this wire be ignored when installing a TCS M1 in a European locomotive?


Picture from: http://www.tcsdcc.com/

Thanks if anyone can clear this up for me! Does this relate in any way to subtle differences between NMRA (USA and UK) and MOROP (European NEM) standards in DCC?
 

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Just another modeller
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QUOTE (goedel @ 9 Feb 2008, 23:09) <{POST_SNAPBACK}>the TCS M1 has seven wires instead of six. What is the extra wire (blue) for? I gather it is some kind of common positive for lighting? Is this only needed on American models because European ones are usually designed differently?

e.g.

(Both models have built in directional lighting, green blobs are cuts to tracks) Pictures from: http://leksicom.co.uk/

So no blue wire needed? Can this wire be ignored when installing a TCS M1 in a European locomotive?

Thanks if anyone can clear this up for me! Does this relate in any way to subtle differences between NMRA (USA and UK) and MOROP (European NEM) standards in DCC?

**Hi Goedel

the blue wire is indeed the common positive for functions. It is actually a compromise not to use it, as the power to lighting functions is less when using a chassis earth instead of blue wire (half wave). It is better to use one if you can in other words.

N scale however has less space in the loco - some EU manufacturers therefore leave off the blue so they have one less wire to worry about... fleischmann also do this in HO, which I find really bad, as it means I have to rewire every FL loco totally to give best accessory performance under DCC!

As to your questions: any decoder with no blue wire can have one added. Any decoder with a blue wire can have it removed to use the chassis as function ground. It is your choice.

There is in reality no difference between MORP/NEM and NMRA - actually for DCC MOROP pretty well rubber stamps & adopts NMRA literally and have ample opportunity for input at the ground level if they wish for it to the NMRA standards. There has never been significant conflict there.

ONLY EU manufacturers have ever used the six pin 651 - and then only N has used it seriously it is actually very rare elsewhere.

Richard
DCCconcepts
 

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Discussion Starter · #3 ·
Thanks very much Richard, that's exactly the sort of answer I was after! By the way, the paint stripper for Mozart works very well - thanks very much for helping there too!

QUOTE (Richard Johnson @ 9 Feb 2008, 14:20) <{POST_SNAPBACK}>ONLY EU manufacturers have ever used the six pin 651 - and then only N has used it seriously it is actually very rare elsewhere.
I got this impression when looking for an explanation on the internet. Righto, I'm off to dig out the soldering iron and burn out some surface mount!
 

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QUOTE (goedel @ 10 Feb 2008, 02:18) <{POST_SNAPBACK}>Thanks very much Richard, that's exactly the sort of answer I was after! By the way, the paint stripper for Mozart works very well - thanks very much for helping there too!

I got this impression when looking for an explanation on the internet. Righto, I'm off to dig out the soldering iron and burn out some surface mount!


Cheers Geodel - I'm pleased the stripper did its job - and good luck with the installs

Richard
 
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