Question: Re-Walthers HO Scale GP9

[mdq]

I have a question in regards to the HO scale Walthers Mainline
 EMD GP9 Phase II with Chopped Nose - ESU Sound and DCC 

Does anyone know how to remove the momentum?

I check the instruction and ESU website, but did not find out how to do (or was blind to it)

Thank you

[jonklein611]

s3.amazonaws.com/aws.walthers.com/WalthersMainline+ESU+Sound+and+DCC+Decoder+CV-List.pdf

CV 3 and 4.

Set them to zero for no momentum.

[Funnelfan]

The ESU decoders also have a delay engine start feature that won't allow the locomotive to move until the sound has revved up. That can get really annoying with switching.

[jonklein611]

Jan 8, 2021 7:46:14 GMT -8 Funnelfan said:

The ESU decoders also have a delay engine start feature that won't allow the locomotive to move until the sound has revved up. That can get really annoying with switching.

Per the sheet, that's off by default.

CV 124 - 0

[mdq]

Thanks for the replies

I did CV3=0, CV4=0, CV 124=0, and it reduced it, however,
when it slows down (almost to a stop) it continue forward
a bit, like lurching..

Very annoying for switching or coming to a stop

[Mark R.]

The ESU Auto-Tune feature will correct that .... assuming it's in the Essential Sound Unit ESU decoder Walthers uses.

IF it does, Place the locomotive on a clear, straight section of track at least (4) feet long. Be sure the current selected direction is forward. When you initiate the procedure, the loco will take off at full speed instantly in the last direction of travel.

Simply set the value of CV54 = 0. Return to operations mode, and select function key F1. The loco will take off on its own and travel a few feet. When it comes to a stop, the bell will be ringing so select F1 again to turn it off.

This usually eliminates any of that jerkiness you are seeing. As a recommendation, I suggest you run the engine for a bit before permorming this as the results will be different whether the engine is cold or warmed up.

Mark.

[edwardsutorik]

Usually, when I do Auto Tune, CV 54 reads "0000". Doesn't matter. Enter "0".


Ed

[mdq]

Yup! CV 54 did not work. Actually it made things worse.
I have reset the decoder to factory default.
I'll do the CV3, 4 = 0 again and CV 124 as well

Not easy to fix [ eliminate] this "momentum" effect on this loco!

[Mark R.]

You could try to de-tune your decoder even further by turning the BEMF off completely and see how it performs - change CV49 to 0. You will probably have to set your starting voltage (CV2) a bit higher to still get it to move at speed step one.

Mark.

[mdq]

Mark that worked!

CV3=0
CV4=0
CV124=0
and
CV49=0

That took care of the momentum. It's gone and it's much better. Big improvement.
I'll check if I can find something for CV2= (?) because it does need more "power" to get going.


Thanks

[Mark R.]

Just read the current value in CV2, then keep raising that value until the engine just begins to move on speed step one.

Mark.