Model Railway Forum banner
1 - 6 of 6 Posts

·
Registered
Joined
·
356 Posts
Discussion Starter · #1 ·
Hi,

I have just chipped an old hornby 4-4-0 compound 4P (R376) that has a smoke unit. I have used a TCS M1 fitting in in the limited space in the tender (tender drive). Worked OK but would not read in the CV's (Using the ESU ). In taking the body off the loco found it had a smoke unit fitted. By dis-connecting the smoke unit it reads in decoder no problem. When the smoke unit is reconnected it appears to run ok with slow acceleration and slow deceleration. As the smoke unit is across the rail pickup is this causing the ESU to trip due to the current when reading the decoder. The decoder is rated at 1.3 amp with peak of 2.0 amps. Is there a suitable decoder to run just the smoke unit, I assume the FL lighting decoders will not provide enough power to drive the smoke unit. I am not able to run the loco other than on the test track as nearly finished the baseboards and start on the track laying.

Ian
 

·
Registered
Joined
·
526 Posts
I would imagine that a smoke unit in parallel with a decoder would confuse it some and give the symptoms you describe. The smoke unit should be hooked into a function on the decoder. One can link two or three functions together to get the necessary power but the M1 instructions will give a figure for the total power output. Blue wire is common positive and yellow and white are for lights and are directional. This leaves green and possibly purple. You will then need to switch on all the outputs using the function mapping CV's.

Older smoke units might well require more power than the M1's outputs can stand. This will require another accessory decoder that can.

The power ratings you are stating in your post are related to the motor power. The function outputs give a lot less.
 

·
Registered
Joined
·
356 Posts
Discussion Starter · #3 ·
Thanks,

The M1 is a 2 function so only has the yellow and white (plus blue) for lights.
I had assumed the power rating was the maximum it would draw from the input power (rails) to supply motor and lights.
Am I understanding your instructions right in that the multiple functions should be connected essentially in parrallel that is common on one side of smoke unit and two or three function wires to the other side and then turn on all these functions.

Ian
 

·
Registered
Joined
·
526 Posts
QUOTE (enM @ 1 Mar 2009, 19:34) <{POST_SNAPBACK}>Thanks,

The M1 is a 2 function so only has the yellow and white (plus blue) for lights.
I had assumed the power rating was the maximum it would draw from the input power (rails) to supply motor and lights.
Am I understanding your instructions right in that the multiple functions should be connected essentially in parrallel that is common on one side of smoke unit and two or three function wires to the other side and then turn on all these functions.

Ian

Essentially yes. It is a blow that only the yellow and white are available as they are directional. White powers forward and yellow powers reverse lights (or vice versa). I am fairly sure that one could map them to other functions if the CV's are in the decoder but I have to admit I am a bit out of my depth with that and would want a good look at both the instructions and DecodePro before altering anything.

In general, the smaller the decoder, the smaller the power available and smoke units need a lot of power.

The alternative is to source another decoder that has suitable function power either as a main decoder or as a piggy back accessory decoder. If the latter, you have the option to have the smoke unit separately switched. No bad thing for longer operating sessions.
 

·
Registered
Joined
·
356 Posts
Discussion Starter · #5 ·
Fine I know the CV's to alter so can make them flash, 50% brightness, reverse connection, etc. I am chipping these for a friend so a bit cagey with experimenting with his decoders. As its a TCS will play and then use the goof warranty if i manage to blow it.
Thanks for your help.
Ian
 

·
Paul Hamilton aka &quot;Lancashire Fusilier&quot;
Joined
·
844 Posts
For what its worth I did exactly as proposed with the same decoder and altered the function output to operate on both fwd and reverse for bothe functions. That way the unit gets enough poer to smoke easily and regardless of the direction the loco is travelling in.
 
1 - 6 of 6 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top