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Aside from the regular quirky fault messages, my MTH steam locomotives do this really weird thing during operation. I turn the DCS handheld to get the locomotive to a given speed.  Then, when the locomotives get to certain areas along the rail they will slow themselves down and then a few seconds later speed themselves back up to the set speed (almost like they are hesitating due to a momentary drop in power). Every time they go around the rail they will do this same thing at the same spots.  Here are some other data points if it helps diagnose the issue:

  • I star pattern wired as closely to MTH/Barry's recommendations as possible;
  • the problem happens within a given track block, not in transition between two track blocks - and, most importantly, the locomotives slow themselves down at different spots on the layout during different operating sessions;
  • I used these same engines when laying the track and tested the entire layout for DCS signal strength, which was "10" throughout;
  • Every time this occurs, I test the areas where these locomotives slow down and then speed up and the multimeter shows the voltage (each main line has independent power coming via its own Lionel Powerhouse 180 brick) is a constant 18+ volts and DCS signal strength is always "10;"
  • The rails are perfectly clean and these are PS2 engines that have a battery in them so even a momentary drop in power (not that there is one) should not matter; and
  • all my Lionel locomotives run just fine over the entire layout at any speed every time - and they don't have batteries as would a PS2 locomotive. 

 

Thanks for any advice. 

Peter 

Last edited by PJB
Original Post

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Peter,

There are some things of which you should be aware:

  • The battery in a PS2 engine does not maintain the engine's speed when power is momentarily interrupted, rather, it keeps it making sounds and keeps it in DCS mode.
  • If it's all of your PS2 engines, it's unlikely that the issue is related to a defect in the engines.
  • I'm not aware of anything in DCS that could cause the issues that you're experiencing.
  • The fact that your other, non-MTH engines don't have batteries has no bearing on the problem.
  • What you're experiencing is power-related, not DCS-related, so DCS signal strength isn't at all a factor.

I suggest that you look at the spacing of the pickup rollers and also at the non-traction tired wheels of your offending engines. It's possible that you may be momentarily losing either Hot (center rail) or Common (outside rails) due to the engine's wheel and pickup roller geometry.

Further, some steamers may not have a good Common connection via the tether between the wheels on the tender and the engine itself.

If the problem happens most often around switch tracks or uncoupling/unloading tracks, loss of Hot or Common is a reasonable possibility.

It would also help to know exactly which PS2 engines exhibit the offensive behavior, as well as more information about the track topology where the issues occur.

Are you running them with the smoke on? Try turning it off.

When you say "Every time this occurs, I test the areas where these locomotives slow down ...."

You test them after running with your meter. Do you have any transformers with amp and volt meters built in? Can you borrow one or install meters?

What gauge wire goes to these blocks? how long is it? how are they connected to the tracks?

how long are these blocks and how many joints?

what type of track are you using?

What type of power?

Does your Lionel engines that run fine, include newer larger steamers with chuffing smoke?

 

Last edited by Engineer-Joe

Thanks for helping me trouble-shoot.  Here's additional data to help:

  • I typically run the steamers with smoke off, although this occurs whether smoke is on or off. 
  • 5 different Premier locomotives including N&W J, Allegheny, Daylight and Mohawk. 
  • Atlas track throughout. 
  • As I said, the issue happens wherever. Usually on areas where there is uninterrupted rail (I don't have uncoupling/loading track and the issue rarely happens, if ever, where there is a turnout). 
  • As I said, I wired as closely as possible per MTH/Barry recommendations, so I have one centrally located drop in each track block that is composed of 9-11 track sections.  Mostly 40" straights with minimum 072 curves, and often 081, 090, 099 and 0108. 
  • The power drops are equidistant OGR wire of 14AWG wire of varying lengths, with none longer than 20', soldered to the track - although this sort of seems irrelevant given the problem happens randomly all over the layout and in track blocks that can have 6' wire runs or 20' wire runs. 
  • Barry - I think your tether point would be a good place to look - but I would point out that I just had MTH replace the tether on the N&W J (the existing one decided to just fall apart during operation).  Maybe this is the problem (?) but to me it seems rather unlikely given the mathematical probability that I could buy 5 different steamers (from 4 dealers) over the course of 4 years and each and every single one having the exact same tether issue from almost day 1. 
  • Barry - per your comment "I suggest you look at the spacing of your pickup rollers and...," can you elaborate?  I'd like to follow up on this, but don't exactly know what to do.  Also, I'd point out that distance between pickup rollers is not the same between steamers (and I've replaced them on 2 steamers in the past year with the more robust version sold by MTH - and this has made no difference), and wheels geometry is also different between steamers. Also, as mentioned, today the issue could happen for (say) steamer 1 every time it is in track block 3 (straight track only) and steamer 2 will experience this today in block 6 (straight leading into 081 curve). Tomorrow, steamer 1 experiences it only every time it is in block 5 (099 curve and some straight) and steamer 2 only every time it is in block 4 (just straight track). 
  • Barry - if by "track topography" you mean straights, curves, etc., then I think the data is above. If, however, you mean are there inclines and declines, then the answer is yes and no.  I have very gentle inclines and declines on the layout but again, this issue happens everywhere.  On perfectly flat areas as well as elsewhere.  There is no increased occurrence level in blocks with inclines/declines over perfectly level blocks. 
  • TIU is rev. L. 

 

Thanks again for for the help

Peter

Last edited by PJB

Peter,

Atlas track throughout.

Do you have both outside rails connected together? If not, try jumpering them together in one of the offending blocks.

Also, meter connectivity between each rail and the adjacent rails within each offending block.

Your problem is almost certainly a loss of contact between the engine's pickup rollers or wheels, and the track, or a loss of connectivity between a power wire and the track..

Barry Broskowitz posted:

Peter,

Atlas track throughout.

Do you have both outside rails connected together? If not, try jumpering them together in one of the offending blocks.

Also, meter connectivity between each rail and the adjacent rails within each offending block.

Your problem is almost certainly a loss of contact between the engine's pickup rollers or wheels, and the track, or a loss of connectivity between a power wire and the track..

Barry,

Thanks again.  All three rails are wired (jumper between commons) in most track blocks and I've run 2 multimeters over each and every piece of track (measured twice - using center and each outside rail) with zero power drops. Also ran 2 Premier locos over the entire layout at 2-3 smph to check for voltage as well as DCS signal strength. Voltage is per multimeters (18+ v) and signal is 10 throughout.  But I'm thinking you're right about power drop.  Can you elaborate on "spacing of pickup rollers/geometry of wheels" comment?  Any other suggestions?  By the way, I know we're trouble-shooting, but keep in mind that my RK Scale and Premier diesels and every Lionel locomotive I own does not experience this issue.  That's what has me thinking it might be a power/tether issue? 

Susan - thanks, but there is zero metal interference - other than the rails themselves and the Atlas screws that hold it down (the TIU is vertical and sits equidistant in the layout). Purposely designed it this way given some such issues discussed wrt Legacy and Lionel locomotives (since we also own several of these). 

Peter

Last edited by PJB
Gregg posted:

Is this happening with lash-ups or long heavy trains?  You may be pushing the limits  of the engine. Does it happen  with just  the engine?

Engineer-Joe and Gregg - just the locomotive. No lash-ups, no cars at all. Going anywhere from 10 smph to 60 smph.  Thanks for your help.

Peter

Last edited by PJB
Barry Broskowitz posted:

Peter,

There are some things of which you should be aware:

  • The battery in a PS2 engine does not maintain the engine's speed when power is momentarily interrupted, rather, it keeps it making sounds and keeps it in DCS mode.

 

Not to derail getting advice on my issue, but I just re-read the above quoted piece  and I'm confused.  According to the MTH DVD from a few years back that intros its products and DCS, there is a scene where they have an MTH train on a track and a non-MTH train on a parallel track.  Along each track there are sections of rail covered with tape, meant to purposely cause a loss of power and signal. The narrator indicates (and the accompanying footage demonstrates) how the MTH PS2 locomotive, with its battery back-up, will keep going - at the same speed - despite the intermittent loss of power. The other train, as expected, craps out.  So, is the purpose of the battery misstated in the MTH DVD or ...? 

Thanks

Last edited by PJB

Sounds like poor conductance at center or outside rail pins.  If the latter, locos pulling different length trains may behave differently.

If a running train loses signal but not power, it will continue running at the same speed until (1) collision, (2) power shut down, or (3) regaining signal and receiving a command.

Last edited by RJR
RJR posted:

Sounds like poor conductance at center or outside rail pins.  If the latter, locos pulling different length trains may behave differently.

If a running train loses signal but not power, it will continue running at the same speed until (1) collision, (2) power shut down, or (3) regaining signal and receiving a command.

Or (4), derailment.

Have you made any observations if you:

1a) turn the engines around and head them in the other direction

1b) run the engines in reverse

Since this doesn't occur on diesels (no tether), 1a) might reveal if "bending" the tether into a left vs. right turn might be in play.  1b) might reveal if the roller/wheel spacing relative to bumps, "potholes", worn-spots on particular sections of track might be in play.

Also, since this apparently occurs at 10 sMPH (or so), when the steamers slow down do the chuffing sounds also slow down and exactly follow the 4-per revolution cadence?  I realize you say the slowdown is only for a few seconds but it might be a diagnostically useful to note if the engine "thinks" it's going at the commanded speed (chuffing sounds don't change cadence) but the mechanics slow down due to a gear slip or some other mechanical anomaly.

If you have a real short 0-4-0, like a Docksider, run it around the layout, deadhead with no cars, in conventional mode.  This will show up any bad grounds.

Barry did ask you to post the loco model numbers, with good reason.

Do any of the problem locos NOT have a ground wiper on the rear truck, or NOT have a rear truck.

Thanks for the responses. Unfortunately, my first two posts aleady answer all of the questions or diagnoses in RJR's and every subsequent response, including: (a) the issue happens everywhere and anywhere on the layout (more detail in my first 2 posts), so "tether angle" is sort of irrelevant given the issue happens randomly on straightaways, curves to the left and right; (b) a power drop is not likely, as every other locomotive - even all my MTH diesels - do not experience the issue, not to mention my consistent 18+ volt multimeter readings throughout (confirmed even by these same steamers' electrical power readings); (c) not the black on the center rail given I already said that signal strength is 10 throughout; and (d) well, I think it's obvious from the list of locomotives I provided that every one of them had a trailing truck, given the smallest wheel arrangement stated in 4-8-2.  

RJR - good question about a conventional test!  I have a Polar Express conventional locomotive and ran it around the tracks repeatedly - it does not experience this issue when run around the track at any speed.

I'm far from an expert in this stuff, but I'm wondering if it has something to do with the wheels on these things not being firmly to spec (as measured by my O scale NMRA metal measuring device thingy) and this variance causing electrical gaps as these things chug down the track? 

Thanks

Peter

You did say originally that it happened in same spots. "Every time they go around the rail they will do this same thing at the same spots."

A steam loco is too long to run the conventional test.  Tender wheels could bridge a ground gap.  My layout had been up for years with no problems, until I ran a deadhead Docksider and found two very short groundless spots.

Reason I asked about a trailing truck is that some locos, with neither trailing trucks nor axle wipers, have experienced ground issues.

Are you sure rolling stock isn't fouling on something?

 

If you can attach a conventional transformer to the layout, run the offending steamers in conventional with speed control TURNED OFF (whistle-bell-bell followed by the 2 toot acknowledgement).  This applies track voltage "directly" to the motor without speed control.  If the engine still slows down then the engine is receiving a reduced voltage or possibly intermittent contact which effectively averages to a reduced voltage.  I suspect you were measuring track voltage on the rail?  What would be useful to know is the voltage the engine gets through the roller/wheel connection; this could be a hassle so the above experiment is a proxy.

Last edited by stan2004
RJR posted:

You did say originally that it happened in same spots. "Every time they go around the rail they will do this same thing at the same spots."

A steam loco is too long to run the conventional test.  Tender wheels could bridge a ground gap.  My layout had been up for years with no problems, until I ran a deadhead Docksider and found two very short groundless spots.

Reason I asked about a trailing truck is that some locos, with neither trailing trucks nor axle wipers, have experienced ground issues.

Are you sure rolling stock isn't fouling on something?

 

Yes, I think I said that in a given running session, a locomotive will experience this issue every time it goes through (say) track block 1 and 3 AND that in the next running session, this same locomotive will only experience this when running through (say) track block 2 and 5.  So the same locomotive that has a problem in one session in one track block has no problem in that same track block in another session. 

I forgot to mention that I have my first locomotive, a beat-to-crap 1973 Lionel Southern Express (2-4-0), which is tiny and doesn't require a tender. It doesn't experience any problems either. 

I think I mentioned above that I am using just the locomotives.  No rolling stock at all. 

Thanks

Peter

Last edited by PJB
stan2004 posted:

If you can attach a conventional transformer to the layout, run the offending steamers in conventional with speed control TURNED OFF (whistle-bell-bell followed by the 2 toot acknowledgement).  This applies track voltage "directly" to the motor without speed control.  If the engine still slows down then the engine is receiving a reduced voltage or possibly intermittent contact which effectively averages to a reduced voltage.  I suspect you were measuring track voltage on the rail?  What would be useful to know is the voltage the engine gets through the roller/wheel connection; this could be a hassle so the above experiment is a proxy.

Stan - thanks for this!  I'll try to do this later or tomorrow and see how it goes. 

Peter

Frankly, the more we're discussing this, the more I'm thinking that it has nothing to do with track or power to track.  If so, it would seem that locomotives other than just my 5 MTH steamers (e.g. MTH diesels and Lionel steamers) would also experience the issue - even if sporadically.  

And, if it's a power drop in track block (say) 2 causing the issue every time the locomotive goes through block 2 (and only through block 2) during session 1, how is it that no other MTH steamer experiences this issue during this same session?  And that the issue miraculously disappears when the locomotive that did experience the issue during session 1 goes through block 2 during session 2 - but has the same issue this time in (say) block 5 (and only block 5)?  And then next running session only in (say) block 7? 

Peter

Last edited by PJB

Peter after reading your topic. I think you are having voltage drop on your track and i will try to explain. This what i have found on my track. I would check voltage it would be fine all the way around my loop but what i found out when i was running the train on the track and check voltage at the same time the voltage would be 1 to 3 volts difference fatherest away from the transformer so i run feeder wires and made sure my track was making good connection. I don't have anymore problems with mine. Even thou you have blocks i say you have that problem in block 5.          

chessie1971 posted:

Peter after reading your topic. I think you are having voltage drop on your track and i will try to explain. This what i have found on my track. I would check voltage it would be fine all the way around my loop but what i found out when i was running the train on the track and check voltage at the same time the voltage would be 1 to 3 volts difference fatherest away from the transformer so i run feeder wires and made sure my track was making good connection. I don't have anymore problems with mine. Even thou you have blocks i say you have that problem in block 5.          

What are "feeder wires?" My current set-up is star pattern wired (14AWG) to each block's central-most piece of track (each block is 9-11 pieces of track). In most blocks, I have a jumper wire (16 AWG) on one piece of track connecting its outside rails.  Thanks. 

Peter

 

Last edited by PJB
RJR posted:

Peter, I suggest that you do your testing with the same train, or better still deadhead, because there are possible effects caused by a train.  There is no reason why only an MTH loco should be affected by the condition.

RJR - good point, I need to attack the issue with a "problem" locomotive.  Problem is, all 5 Premier steamers have the same issue. Each does the same thing - randomly. As an example: Today loco1 slows down/speeds up in track block 1, loco2 slows down/speeds up in block 3 and so on. Tomorrow, loco1 only slows down/speeds up in block 5, loco2 only slows down/speeds up in block 8, and so on.  What is the "control" in all this, given the issue disappears and then appears elsewhere?  I mean, this is a constantly moving target!

I guess I could start with just one of these locomotives and test by running it conventionally.  Just don't know what to do if either (a) it runs into this issue but all testing shows the "offending track area" is getting proper juice and no other locomotive has an issue in that spot; or (b) in testing, it does not experience any problems....

Thanks. 

Peter

Peter feeder wire is running from your power to your section of track. I would check your wiring could have bad solder joint or wire could be corrded inside or broken inside and i would spray electric contact cleaner to your track joints.I don't believe its your engines being all five doing it. Its in your wiring somewhere and i would hook up temporary wires to that section to power supply see if that helps.    

Early on PBJ said the slowdowns occur even with at 10 sMPH.  Even if there were huge voltage drops from wiring or whatever, it's hard to believe this drop would be more than a few Volts.  Any PS engine (with no rolling stock load) will run 10 sMPH in command mode with only 12V on the track.  So for it to slow down in command mode (i.e., when commanded to 10 sMPH), the voltage the PS boards receive (after going thru the wheels and rollers) would have to drop below 10V or so.

Hence, I'm curious what happens with the problem engines when run in conventional with speed control TURNED OFF. 

chessie1971 posted:

Peter feeder wire is running from your power to your section of track. I would check your wiring could have bad solder joint or wire could be corrded inside or broken inside and i would spray electric contact cleaner to your track joints.I don't believe its your engines being all five doing it. Its in your wiring somewhere and i would hook up temporary wires to that section to power supply see if that helps.    

chessie1971 - as I mentioned in my OP, I have electrically isolated track blocks and only one power drop in each block.  Forgive my ignorance, but if that one power drop in a given block is not supplying power, then the block is getting zero power. How is it possible for my multimeters (and the DCS data coming from the locomotive) to be showing 18+ volts (and DCS signal strength a perfect 10) and the engine itself deciding to resolve the issue in that same track block - a block with no power?  Also, no other locomotive in that same session experiences any problems in that block, nor does that same locomotive (usually) during the next session.  

FYI - I checked the solder points throughout and they all look good. All power drops run through the homasote and plywood to a "secure" point that does not allow them to be snagged or pulled, and they are secured all the way to the power board to avoid any kind of internal wire breakage or "flickering" due to being loose. 

Thanks 

 

 

 

Last edited by PJB
stan2004 posted:

Early on PBJ said the slowdowns occur even with at 10 sMPH.  Even if there were huge voltage drops from wiring or whatever, it's hard to believe this drop would be more than a few Volts.  Any PS engine (with no rolling stock load) will run 10 sMPH in command mode with only 12V on the track.  So for it to slow down in command mode (i.e., when commanded to 10 sMPH), the voltage the PS boards receive (after going thru the wheels and rollers) would have to drop below 10V or so.

Hence, I'm curious what happens with the problem engines when run in conventional with speed control TURNED OFF. 

I guess I should mention too that the slow down/speed up issue often occurs all in the same electrically isolated block. Meaning, the issue starts in one block and resolves itself in that same block.  The locomotive doesn't need to leave that block and enter the next one for the issue to resolve itself.  Not saying it always occurs in one block, but it often does.  

C. Jones - no, I haven't done this and will (thanks), but I will say that I had this issue from before we even owned Legacy.  What I can't recall is if we had it before we had TMCC.  Will def check.  

Thanks

 

 

Peter

Last edited by PJB
PJB posted:
Gregg posted:

Is this happening with lash-ups or long heavy trains?  You may be pushing the limits  of the engine. Does it happen  with just  the engine?

Engineer-Joe and Gregg - just the locomotive. No lash-ups, no cars at all. Going anywhere from 10 smph to 60 smph.  Thanks for your help.

Peter

whaaatt?

I asked if you tested the track under load, not the engine.

Casey Jones2 posted:

I don't know about this...I've never tried using it but it almost sounds like the problem locos have been programmed with the route/ record function?   

Who knows for sure. but go to Advanced /Record playback/select the tiu and then select each secession and use the soft-key " stop secession...". Having said that , there's usually a "P" in the remote's screen indicating the engine is in playback mode. (if things are working correctly)

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