Re: Difficulting reading back CV's in N-scale locomotives


wirefordcc <wire4dcc_admin@...>
 

They didn't say a whole lot, did they?

Their phrase "the decoder must see a load" is partially correct.
Since the decoder is connected to the motor, you can say that the
decoder sees the motor. But the decoder doesn't do anything with
this. It merely causes a load to be seen by your command station.
Your command station is what registers the presence of the motor.

I do agree that if the decoder works with another motor, the decoder
is working correctly.

Their advice about connecting a resistor across the motor is also
valid. It would have been nice if they suggested a value. I'd
start with 100 ohms and work down to say 20 ohms if need be. Since
you are talking N-scale, you probably don't have room inside the
locomotive to leave the resistor. Use AT LEAST 1/2W resistor.
Don't leave it attached, it will smoke.

There was something else I intended to say earlier, but forgot.
There are only 2 sets of CVs you need to program in the program
mode. 1. The address CVs (either CV 01 for short addresses or CV 17
& 18 for long addresses) and 2. the configuration CV 29. Everything
else you can program on the main in Ops mode, which does not try to
read back CVs. You won't be able to read CVs back in Ops mode, but
you also won't get noPG or noID in this mode.

Allan

Mike,

You asked some very good questions. I'm curious as to what
Digitrax
told you. They should have answered your questions.
This was Digitrax's answer:

To program, the decoder must see a load on the motor outputs.
We are not aware of the programming problem with this particular
motor with the DZ143.
That the decoder programs with another type motor proves that the
decoder is OK.
You might add an additional resistor across the motor leads to
increase the load and lave it in place for future programming
changes or remove after programming.

Hope this helps

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