Engine speed

[MikeN8FWD]

Hello,

I am using a MRC Prodigy Advance Square and some of my decoders will not move until my throttle is on 12 or 14. for example using a digitrax dh-123 in a switcher sw1500 Athearn ready to roll and on default settings it has to be on 14 to go and I have tried the settings for a switcher and no luck. Is it because it is an older decoder as I have a few older engines with older decoders.

Thanks Big Mike

[MisterBeasley]

How much voltage is going to the track?  Some DCC systems allow different voltage levels depending on the scale of your trains.  Also, does your system use a separate power supply and is it up to the task?

Are these new engines with new decoders?  Old engines might be gummed up with dried grease and a previous owner might have played with decoder settings.

[gregc]

MikeN8FWD

I am using a MRC Prodigy Advance Square and some of my decoders will not move until my throttle is on 12 or 14

most motors won't starting moving until there are at least a few volts on the rails.  CVs can be set to set the starting voltage.  (see DCC CV 3,5 and 6)

the decoder setting is more of an speed setting if the encoder has BEMF and it is enabled.   at setting 1, the decoder will monitor BEMF to set some minimum voltage that causes the motor to move. 

[tstage]

Mike,

Are you able to read CVs with your Prodigy Advance Square?  Read what the value is for CV2, which is call Vstart.  If you raise the value slightly you should notice that your locomotive still start out at a lower setting on your MRC PA² throttle.  Continue to raise the value until your switcher just begins moving at setting "1" then save that value in your decoder.

Digitrax has good motor-control.  If you really want exceptional motor-control, go with a TCS or ESU motor-only decoder.  Yes, it will cost you a little bit more but it's worth it for slow speed switching, which is what you really want with a switcher.

Tom