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Need some help with speed matching

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  • Member since
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  • From: Maryville IL
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Need some help with speed matching
Posted by cudaken on Sunday, April 26, 2009 9:42 AM

 OK, sorry to be a pain again. Simon 1966 has been out of town, so there is no hands on help lately.

 I have two PK F-3's that run well together. Simon speed matched at his house so I have no idea what was done to them. I all so have not figured out the PR 3, so I have not been able to read there CV's.

 All three F-3's have DH 123 decoders. I have sat CV 2, CV 3 and CV 4 to the same settings. New B unit takes off quicker and will run down the other 2 in a foot. I have been reading the Digitrax Manual and it does make my head hurt. Looks like maybe CV  5 or 6 might be the ones to try next. 

 On CV 2, 3 and 4, should I make them all 00 till I get the new B speed right?

 Thank in advances, I know you guys are getting sick of seeing my questions.

           Cuda Ken 

I hate Rust

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Posted by Hamltnblue on Sunday, April 26, 2009 12:34 PM

First adjust vstart until they just move and at the same speed on speed step 1.

Second adjust one engine's vmax. I usually set it to 200.

Then adjust the other engine to the same setting.  Vmid might not be needed or supported.

Run both engines at an increasing speed step to see if they run close. If not adjust the second engine up or down as needed.  Repeat until they match. 

If you have a 3rd engine you simply do the same thing with that one.

If there is bemf turn it off when consisting.

 

Springfield PA

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Posted by CPbuff on Sunday, April 26, 2009 4:49 PM

Good article in MR Sept 2006, should help!

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Posted by cudaken on Sunday, April 26, 2009 10:22 PM

Hamltnblue
Second adjust one engine's vmax. I usually set it to 200.

 Hamltnblue, which V Max CV 05 or CV 06?

 

 Guess Randy gave up on me.

           Cuda Ken

I hate Rust

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Posted by mfm37 on Monday, April 27, 2009 4:30 AM

CV2 is start voltage

CV6 is mid voltage

CV5 is max voltage

Not all manufacturer's decoders use all three of these CV's.

ALL Digitrax decoders use these three CV's.


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Posted by Rangerover on Monday, April 27, 2009 7:41 AM

cudaken

 OK, sorry to be a pain again. Simon 1966 has been out of town, so there is no hands on help lately.

 I have two PK F-3's that run well together. Simon speed matched at his house so I have no idea what was done to them. I all so have not figured out the PR 3, so I have not been able to read there CV's.

 All three F-3's have DH 123 decoders. I have sat CV 2, CV 3 and CV 4 to the same settings. New B unit takes off quicker and will run down the other 2 in a foot. I have been reading the Digitrax Manual and it does make my head hurt. Looks like maybe CV  5 or 6 might be the ones to try next. 

 On CV 2, 3 and 4, should I make them all 00 till I get the new B speed right?

 Thank in advances, I know you guys are getting sick of seeing my questions.

           Cuda Ken 

Ken, with the PR3 and the JMRI program, I believe it was in the 4th video, they show how to consist using JMRI, you simply adjust the speed table to match the slowest loco, and it's kind of hit and miss with readjusting a couple of times. If you  need help setting up your PR3, give me a call and I'll help you set it up. Using the Bachmann was if you recall, you just put both loco's on the program track and program to #1,2,4,5, etc, on your controller. I did speed match the old fashioned way using 2 loco's that were the same or at least close in speed and put the faster loco as head for consist. But with the PR3 it's much better, and with some patience, you can darn near get them at the same speeds.

davidmbedard , I now understand and realize the difference of the Bachmann system and it's limitations as you tried to explain in threads to guys like me who defended the system with the limited upgrades I did with mine. There are not much in the Bachmann decoders to change, apparently Lenz under the direction of what Bachmann needed to produce a cheap, extremely simple, cut down, omit, decoder system for their market to sell DCC equipped loco's for $35.00. They are a little more these days, however the same limited decoder, but it all comes down to "you get what you pay for". I'm frustrated with a pair of Spectrum Dash 8, 40 CW's I bought for a good price on eBay, brand new. I installed a digitrax decoder I had in one engine and there are 2 black or very dark blue capacitators that got angry and I smelled them burning, apparently I can only use the Bachmann decoder. It still runs fine on DC, they are good runners. LOL I rather enjoy "playing" with cv's and I'm going to call Tony's and see if he has a recommendation for a conversion light board and DCC decoder, I do like the loco and really wanted to put sound in it. Something to play with.

David, you got through my thick head and I am going to move up to one of the Digitrax systems eventually. I didn't realize what I was missing! Thanks for your patience, Jim

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Posted by simon1966 on Monday, April 27, 2009 3:23 PM

Hi Ken,

I am in Seattle this week.  At this rate I am going to be bringing my locos to you for speed matching, you are going to be the expert!

 Best wishes

Simon

Simon Modelling CB&Q and Wabash See my slowly evolving layout on my picturetrail site http://www.picturetrail.com/simontrains and our videos at http://www.youtube.com/user/MrCrispybake?feature=mhum

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  • From: Metro East St. Louis
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Posted by simon1966 on Monday, April 27, 2009 8:55 PM

The assumption with a 3 point speed match is that the motor/locos respond in a linear way.  I had real problem matching the original 3 F units because one of the A's had a totally non-linear response.  It took off like a jack rabbit at low voltages.  The only way I could get it to work was with speed curves to compensate.

Simon Modelling CB&Q and Wabash See my slowly evolving layout on my picturetrail site http://www.picturetrail.com/simontrains and our videos at http://www.youtube.com/user/MrCrispybake?feature=mhum

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Posted by Hamltnblue on Monday, April 27, 2009 9:20 PM

For the most part they are usually close enough.  I typically concentrate on the first half of the speed table since I won't run a consist past there with a large train. 

Springfield PA

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  • From: Maryville IL
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Posted by cudaken on Tuesday, April 28, 2009 10:20 AM

 David B, thanks for the answer. After I get the base line of engine 1 the way I want and find the correct CV 2 setting of the second engine, then adjust CV 5 and 6 so the second engine runs the same as engine 1. Sounds simple, bet it is harder than it sounds!

 Jim, I need to sit down and read the help section for Decoder Pro. Later today I maybe giving you a call. My computer has personal problems, and does not like USB connections. Sometimes I have to unplug the Mouse, plug back in, then unplug the keyboard and plug back in to get the keyboard to work. Ever time I plug in the PR 3 computer says it has found new hardware.

 Simon, looking forward to seeing you again.

 Thanks to all that have answered.

           Cuda Ken 

 

I hate Rust

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Posted by wjstix on Tuesday, April 28, 2009 2:02 PM

cudaken

 OK, sorry to be a pain again. Simon 1966 has been out of town, so there is no hands on help lately.

 I have two PK F-3's that run well together. Simon speed matched at his house so I have no idea what was done to them. I all so have not figured out the PR 3, so I have not been able to read there CV's.

 All three F-3's have DH 123 decoders. I have sat CV 2, CV 3 and CV 4 to the same settings. New B unit takes off quicker and will run down the other 2 in a foot. I have been reading the Digitrax Manual and it does make my head hurt. Looks like maybe CV  5 or 6 might be the ones to try next. 

 On CV 2, 3 and 4, should I make them all 00 till I get the new B speed right?

 Thank in advances, I know you guys are getting sick of seeing my questions.

           Cuda Ken 

One misconception a lot of folks have going into speed matching is that if you put the same value into the same CV's, that will somehow cause the two engines to run at the same speed. It doesn't work that way, what you're doing in speed matching is compensating for the differences in the two engines by putting different values in the CV's.

CV 2 controls the starting power - how much power the engine gets at speed step one. If one engine starts before the other, increased CV2 of the slower engine will make it start sooner - it will get more power at step 1 than the other engine.

CV 3 and 4 are the starting momentum and stopping momentum. If both engines have CV3 set at say 15 and one starts before the other, try reducing CV 3 of the slower engine to say 12 or 10. That will lessen the effect of the momentum and allow it to get up to speed sooner.

Stix

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