I cleared a long dead PK2 E-6 from the RIP track. I want to speed match it to my PK1 PA's. Problem I am having is the E-6 starts out at a higher throttle setting than the PA's. I run Digitrax SEB with a DT400. PA's start moving at 1 while the E-6's does not move till around 17.
I lubed up the E-6 and ran it on DC till I was sure it was in working order. I had the test rails blocked so the E-6 could not move and at WOT it pulled .37 amps and stalled at .65 amps. Motor seems to be in good shape I think.
Engine has a DH 163 decoder and I have sat CV 65 to 35 (Think that is kick start) CV 2 is now 30 and CV5 and 6 is still at the stock settings. Engine will lurch forward at 1 then stops till I get to 15 or 17. While this better than I started with, will not work well with the PA's. CV 3 and 4 are all so at 0.
Am I missing a CV that I should be tweeking? At what point does CV 6 kick in?
Thank you for the coming answers, Ken
I hate Rust
You might have CV65 too high. ANd you may have BEMF off in this one. Here's how to tune it (it's for a DN142 but they are all the same, same CVs)
http://www.digitrax.com/tsd/KB537/dn142-turning-on-back-emf/
Set CV2 back to 0 before doing this, once you have it running as good as it gets, then you can boost CV2 if necessary so that it starts moving at step 1.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Randy, are you saying the DH-163 might be causing the problem? What if I use a DH-123, you think that might help?
My PA's both have DH-123.
Ken
No, theoretically you should be able to get BETTER slow speed with the DH163 since it has BEMF, the DH123 does not. Default for BEMF used to be 6 (out of 0-15) for the strength, but that DN model defaults to 0, menaing no BEMF - your DH163 may be the same.
It may end up being easier to put the same decoder in - although if they are different runs they may have different gear ratios and so will be hard to match no matter what - but you really should be able to get the DH163 one to creep slower than the others on step 1 once you adjust the BEMF as outlined in the pdf file I posted.
Reminds me of the first locos I put decoders in, and why I much prefer TCS decoders these days - the first decoders i put in were DH163L0 in some Proto Geeps. They ran ok just using the defaults, but as I read the decoder manual I decided to experiment with the BEMF settins, and bit by bit, adjusting a little bit at a time as suggested in that document, I got the tweaked even better, though they always had 2 wierd jumps at about 1/3 and 2/3 throttle. This is the cumulative rounding error in the BEMF equation being collected (There are certain numbers that are not easily represented in binary as they result in repeating decimals, like 2.888888888888888... At some point it has to be cut off to be sotred in the decoder as a binary number so you lose part of the value. Do that 100 or 1000 times and the cut off portion adds up to a significant value). Anyway, the Series 6 decoders are supposed to be much better at BEMF, but now I'm entrenched with TCS so I don;t bother. With TCS, you put the decoder in, give it an address, and for the first little while it runs al ittle rough, then it settles down to where it will creep 1 tie at a time and you don't even need to put any value in CV2, unless trying to match it with another loco that leaps into action on step 1.
Randy you where right of course! Do all of Digitrax decoders come with BEMF turned off?
I sat the BEMF CV to 6, kick start is now 5 (could not help my self ) and CV 2 is at 0. Engine now moves at 4, so I will play with it latter. But 4 is a far cry from 15 to 17!
Thank you Randy, if it was not people like you I go back to DC!
It used to come set at 6 for standalone and 0 for consisting - but that only applies to CV19 consisting, so Digitrax users were unaffected. You see posts about it all the time, Digitrax decoder, using NCE, loco ran great by itself but when consisted it needs to be turned way up to move, etc. I guess the new default is off altogether. I haven't picked up any Digitrax decoders in years. The manual even says the default is 6, but there was that tech support deport article for the N scale one that said it was off by default.