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I posted this in the subway forum, but didn't get a response.  So I deleted it and moved it here.

Recently purchased a used R-26 Railking subway set.  With a current lack of TIU's for DCS I have been told by multiple forum members that I can run it conventionally.  So I did that today using a KW postwar transformer.

The KW puts  puts out around 16 volts or so at full power (measured at the track), but it seems to require full power just to pull the four cars at a reasonable speed.  The throttle is pretty much full.  That's a first for amything I have run with the KW.

It is underpowered enough that it derails on 027 curves because the three heavy cars drag on the front powered car pulling the wheels it off the track on the curves and tripping the breaker.  I have a 7.5 amp Sensata circuit breaker in line with the variable A terminal and a single TVS diode across the Lock on.  It is a simple 4 x 8 layout.

I had multiple power taps, but for testing purposes I disconnected them all to favor a single lockon.   I have a 2026, Williams GP38, MTH trolley, and a Williams steamer and none of them require that kind of power using the same setup.

Any ideas?

Thanks,

John

Last edited by Craftech
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@Craftech posted:

  ...snip...The KW puts  puts out around 16 volts or so at full power (measured at the track), but it seems to require full power just topull the four cars at a reasonable speed.  The throttle is pretty much full.  That's a first for anything I have run with the KW. ...snip... Thanks,John

The lead subway car is the only motor car pulling this train:

Note that the transformer was a KW.

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@PRRMP54 posted:

The lead subway car is the only motor car pulling this train:



Note that the transformer was a KW.

Are you at or near full throttle?

Or are you suggesting that maybe there is something wrong with my subway engine?

Also, it does say 031 curves are minimum, but I usually don't have a problem with my 027 tubular track on 031 stuff.  I do have standard O Gauge track.  Maybe that will make a difference with derailments.

John

@Craftech posted:

Are you at or near full throttle?

Or are you suggesting that maybe there is something wrong with my subway engine?

Also, it does say 031 curves are minimum, but I usually don't have a problem with my 027 tubular track on 031 stuff.  I do have standard O Gauge track.  Maybe that will make a difference with derailments.

John

I do not remember the throttle setting and it was O-48 Fastrack. Come to think of it, the transformer may have been the CW-80 that came with the HHP-8 starter set that the track came with.

A suggestion would be to lubricate all of the axles if you have not done so.

Good luck with it, I like the subway stuff and have mostly Chicago such as the ones in the video.

A fully functioning KW should have no problem operating this set.  Try lubricating each of the eight wheels on each of the non powered cars. After applying a drop of oil to each wheel, spin them with your thumb to get the oil to work its way into the block that holds the axel.  You should notice the wheels spinning easily after a while. Then oil and grease the engine lightly per the engine instructions. If this is a used engine, check the gears to make sure there is no debris stuck in there, slowing down your engine and remove anything if you see it.  Doing all that should help ease the drag of the non powered cars and smooth out your engine.  If that doesn’t work, you either have an issue with the KW or the engine.  

A fully functioning KW should have no problem operating this set.  Try lubricating each of the eight wheels on each of the non powered cars. After applying a drop of oil to each wheel, spin them with your thumb to get the oil to work its way into the block that holds the axel.  You should notice the wheels spinning easily after a while. Then oil and grease the engine lightly per the engine instructions. If this is a used engine, check the gears to make sure there is no debris stuck in there, slowing down your engine and remove anything if you see it.  Doing all that should help ease the drag of the non powered cars and smooth out your engine.  If that doesn’t work, you either have an issue with the KW or the engine.  

I actually did all that.  The engine was jerky at first, but smoothed out after I lubricated everything.

I could blow out the gears.  It doesn't say to lubricate the gears.  

Any ideas about how to check the engine?

Thanks,

John

@Craftech posted:

I actually did all that.  The engine was jerky at first, but smoothed out after I lubricated everything.

I could blow out the gears.  It doesn't say to lubricate the gears.

Any ideas about how to check the engine?

Thanks,

John

Before opening up the engine, I would check the power source to make sure its fully functioning.  You can do this by trying the engine on a different layout or borrowing someone else's transformer. Do you know a local fellow hobbyist with a layout nearby or a train club?  Have you run other PS2 engines  on the track and, if so, do they run the same? If you know someone with a DCS system (train club, hobby shop, or friend), take the engine to them and have them go to the menu for the engine, then set it to conventional or have them do a factory reset.

All of my subway engine instructions recommend a small drop of oil on the axle/pin part holding the gears in place as well as the wheel axles of the engine.  A small dab of grease on the gear teeth is also recommended.  Inspect the gears well and use your finger nail to move them and ensure there is no debris binding them.  Since the engine is old, you may want to unscrew the truck from the motor and make sure the worm gear has sufficient grease on all its teeth.  Since the engine is an older model, it is possible that the factory grease on the worm gear has dried up and never been re-lubricated.

Only after all of the above has been tried without success would I then open up the engine and remove the interior casing. Then you can search for a pinched motor or tach reader wire or some other pinched/loose connection. This is really a "hail Mary" check before bringing the engine to an authorized service technician.



Good Luck!

Last edited by Strap Hanger

Before opening up the engine, I would check the power source to make sure its fully functioning.  You can do this by trying the engine on a different layout or borrowing someone else's transformer. Do you know a local fellow hobbyist with a layout nearby or a train club?  Have you run other PS2 engines on the track and, if so, do they run the same?

All of my subway engine instructions recommend a small drop of oil on the axle/pin part holding the gears in place as well as the wheel axles of the engine.  A small dab of grease on the gear teeth is also recommended.  Inspect the gears well and use your finger nail to move them and ensure there is no debris binding them.  Since the engine is old, you may want to unscrew the truck from the motor and make sure the worm gear has sufficient grease on all its teeth.  Since the engine is an older model, it is possible that the factory grease on the worm gear has dried up and never been re-lubricated.

Only after all of the above has been tried without success would I then open up the engine and remove the interior casing. Then you can search for a pinched motor or tach reader wire or some other pinched/loose connection. This is really a "hail Mary" check before bringing the engine to an authorized service technician.



Good Luck!

1.  Will try my 1033 (less power, but worth a try)  This is my first MTH (except for the Bump N Go Trolley which requires very little power).   I also have a 64 Watt.

2.  All oiling instructions were followed.  I will apply a dab of grease to the truck gears.  The internal worm gear has plenty of factory grease - I looked.  It is not that old actually and it is a PS3 without the DCS / DCC switch so maybe 2012?

3.  I checked to see if the tach flywheel and other motor flywheel spin freely.  They do.

4.  Given the way that the capacitors have to charge first in conventional before it will power up and move, HOW CAN I CHECK to see if BOTH motors are turning?

5.  The forum member I bought it from ran it on DCS, but I don't believe it is exhibiting any signs that it needs a reset to run on conventional.  Stops / starts/ reverses/ automatically moves after announcements, etc.

Thanks,

John

EDIT:  PROBLEM PARTIALLY SOLVED.  Engine had "Speed Control" enabled.  One quick horn + two quick bell presses followed by a two horn blast confirmation and speed control was disabled.  It takes off like a bat out of heck now.

BUT, it resets itself to Speed Control ON every time you turn off the power and start it up again.   Directions say that is normal.

Last edited by Craftech
@Craftech posted:

1.  Will try my 1033 (less power, but worth a try)  This is my first MTH (except for the Bump N Go Trolley which requires very little power).   I also have a 64 Watt.

Good move

2.  All oiling instructions were followed.  I will apply a dab of grease to the truck gears.  The internal worm gear has plenty of factory grease - I looked.  It is not that old actually and it is a PS3 without the DCS / DCC switch so maybe 2012?

This was originally made in a PS2 version. I thought you had that one.  However, Its still good that you checked the grease. I apply another dab to my worm gear after 5 years. This is still well within that range.

3.  I checked to see if the tach flywheel and other motor flywheel spin freely.  They do.

Good sign. I also assume you didn't see any pinched or loose wires while you were looking

4.  Given the way that the capacitors have to charge first in conventional before it will power up and move, HOW CAN I CHECK to see if BOTH motors are turning?

Easy. Just remove the shell  and place the engine on the track without the shell on. Then turn on the power gradually. You should be able to see the fly wheels moving on both motors. If the interior plastic shell is obstructing your view, remove that. The engine will still run, albeit without interior lights.

With



5.  The forum member I bought it from ran it on DCS, but I don't believe it is exhibiting any signs that it needs a reset to run on conventional.  Stops / starts/ reverses/ automatically moves after announcements, etc.

Some of these DCS engines display weird behavior when only run in command mode and then switched to conventional.  That's why resetting may help. When run in conventional, the power requirements are significantly LOWER for these DCS subway engines, since the speed control is disabled.  I am able to run all of my subway engines in conventional mode at high speed with just 10-14 volts depending on how many cars are being pulled.  The fact that your engine is not doing this makes resetting it well worth a try.

Thanks,

John

Last edited by Strap Hanger

Excellent! Saw your edit, So it was locked in speed control, huh? That would do it and why the reset was a good idea. For some reason, when only run in DCS, some these engines don't transition to conventional well. I have no idea why your engine keeps reverting back to command speed control.  Once fully factory reset, that should cover it.  Try doing a full factory reset with the DCS system and see if that keeps.

Excellent! Saw your edit, So it was locked in speed control, huh? That would do it and why the reset was a good idea. For some reason, when only run in DCS, some these engines don't transition to conventional well. I have no idea why your engine keeps reverting back to command speed control.  Once fully factory reset, that should cover it.  Try doing a full factory reset with the DCS system and see if that keeps.

I don't have a DCS system.  I got into the MTH game too late.  Maybe when the new WiFi TIU comes out, I'll switch over.  For now, the manual says it reverts back when the power is off so I guess it is normal.  It's easy enough to turn off each time.  The whole conventional operation are multiples of horn and bell combinations so it is par.

Thanks,

John

That's strange. I run my red and green PS2 Lo-V sets occasionally under the Christmas tree (powered by a z-1000 without DCS) in conventional mode and they always start up properly in conventional without the speed control engaged. I have run a few of my PS-3 in conventional on my DCS controlled main layout, but i always go into the DCS menu and set it to conventional. I assumed it turns back to command when it received the DCS signal on its next run session, telling it to start up in command mode. This is what happens with my PS2 engines when I run them in conventional on my DCS powered tracks in the same manner.  From what you are saying, the PS-3 engines revert back to command speed control even without receiving a DCS command signal.  That's a ridiculous design by MTH and is very different from the PS-2 models.  When I get a chance, I'll set up a carpet loop and test it out and see if I get the same result as you on a sampling of my PS-3 engines.

Last edited by Strap Hanger

Railking Subway Operator's Manual.pdf (Below)

Page 12

Speed Control
M.T.H. engines equipped with Proto-Sound 3.0 have speed control capabilities that allow
the engine to maintain a constant speed up and down grades and around curves, much like
an automobile cruise control. You can add or drop cars on the run, and the engine will
maintain the speed you set.
While the engine is programmed to start with the speed control feature activated, you
can opt to turn it off. This means the engine's speed will fall as it labors up a hill and
increase as it travels downward. It is also affected by the addition or releasing of cars
while on the run. Because the engine will run more slowly at a given throttle voltage
when speed control is on than when it is off, you should adjust the throttle to a lower
power level for operation with speed control off to avoid high-speed derailments.
When speed control is off, the volume will drop to allow for better low voltage
operation.
To turn speed control on and off, put the engine in neutral, then quickly tap the
transformer's Horn button one time then quickly tap the Bell button two times,
allowing approximately ½ second to lapse between each quick button press. Two horn
blasts will indicate that the engine has made the change. Repeat the 1 horn, 2 bells code
to return it to the other condition. You will want to do this during the initial neutral
upon start-up if you ever couple this engine to another engine that is not equipped with
speed control to avoid damaging the motors in either engine. Each time you shut down
the engine completely, it will automatically turn speed control on.
Horn Place Engine into Neutral Bell Bell = Speed Control Two Horn Blasts (indicates change is made)
Repeat to Return to Normal Condition

John

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Last edited by Craftech
@Craftech posted:


...

EDIT:  PROBLEM PARTIALLY SOLVED.  Engine had "Speed Control" enabled.  One quick horn + two quick bell presses followed by a two horn blast confirmation and speed control was disabled.  It takes off like a bat out of heck now.

BUT, it resets itself to Speed Control ON every time you turn off the power and start it up again.   Directions say that is normal.

Since it is "normal" for Speed Control to turn back ON between operating sessions, what is/are the remaining issues?

In round numbers, in conventional with Speed Control, PS2/PS3 engines follow a speed vs. track-voltage curve.  I don't have an MTH subway, but all engines I've seen run about 20 sMPH at 12V AC...and then about 20sMPH/Volt above that...so 40 sMPH at 13V, 60sMPH at 14V, etc.  I realize you aren't using command-control so scale speed may not be relevant or of any interest...but having actual numbers can be useful for troubleshooting/discussion purposes.  That is, one person's "bat out of heck" may be another person's "stroll in the park".

If you're so inclined, run a few experiments measuring how long it takes the engine (with and without cars) to run a loop at different voltage settings. 1 sMPH = 0.37 inches/sec.  Let's say your 4x8 is a 20 foot long loop (240 inches of track).  And at some voltage it takes 30 seconds to run the loop.  That's 240 inches in 30 sec = 8 inches/sec or about 22 sMPH.  A typical PS2/PS3 engine in conventional with Speed Control ON should run that fast with12V AC on the track.

As for troubleshooting, with Speed Control ON, does the speed significantly slow down when you pull 3 cars vs. running by itself?  This could point to a wiring issue with too much voltage drop from the transformer to the engine.  One supposed advantage of Speed Control (in conventional) is you shouldn't have to constantly "fuss" with the throttle when going around curves particularly at slower speeds.  That is, without Speed Control an engine might slow to a stop when going around a curve requiring constant adjustment of the throttle...which of course may be part of the fun (or not).

That's strange. I run my red and green PS2 Lo-V sets occasionally under the Christmas tree (powered by a z-1000 without DCS) in conventional mode and they always start up properly in conventional without the speed control engaged

....

From what you are saying, the PS-3 engines revert back to command speed control even without receiving a DCS command signal.  That's a ridiculous design by MTH and is very different from the PS-2 models. 

There may be a different interpretation of Speed Control.  How do you know Speed Control is NOT engaged on your Christmas Lo-V with a Z-1000 controller?  Speed Control in PS2/PS3 means that the flywheel tach stripes are used as tachometer to regulate speed.  In command mode, the DCS remote explicitly sends a sMPH target speed.  In conventional mode, the PS2/PS3 electronics measures the track voltage and maps that voltage to a sMPH target speed.

When Speed Control is turned off in conventional, the flywheel stripes are ignored (for speed regulation) and whatever voltage level is on the track is applied to the motor... in other words no feedback.  There is no ability (or reason) to turn off Speed Control in command mode because the engine would rocket at 18V without the benefit of the tach feedback.  In fact, a common problem is the DCS command engine that rockets irrespective of commanded speed.  In 99.9% (I'm making this number up) of the cases this is because there is a problem in the flywheel tach.  In other words, the electronics gets no feedback from the tach and thinks the engine is not moving; it then applies more and more voltage which makes the engine run faster and faster until it flies off the track or worse.

The PS2 and PS3 Speed Control should behave the same.

@stan2004 posted:

How do you know Speed Control is NOT engaged on your Christmas Lo-V with a Z-1000 controller?

.

The speed control is not engaged and I can easily see it because there is no compensation to maintain a set speed over tight curves and inclines. When speed control is engaged, you can easily see this compensation, allowing the train to maintain a constant speed in such circumstances, unlike on my Christmas layout when I run my PS2 Lo-Vs in conventional mode. Moreover, when the speed control is engaged, just like the original poster mentioned, the engine requires substantially more voltage to move. When speed control is set to off, the engine runs like a speed demon at low voltage.  Its for those reasons, plus the lack of any such disclosure as cited above in the manual as there is for the PS3 model, that I am certain its not engaged when I run my PS2 engines in the manner I noted above.  As for this thread, I'd say the issue is fully resolved in light of the PS3 manual language.

Last edited by Strap Hanger

... Its for those reasons, plus the lack of any such disclosure as cited above in the manual as there is for the PS3 model, that I am certain its not engaged when I run my PS2 engines in the manner I noted above.  As for this thread, I'd say the issue is fully resolved in light of the PS3 manual language.

ps2 5V engine with speed control default ON

I googled "MTH PS2 manual" and the first entry that popped up was this SD-45 which happens to be a PS2 5V version so 15-20 years ago.   The manual clearly states "Each time you shut down the engine completely, it will automatically turn speed control on."

So apparently MTH changed the Speed Control to default=OFF for some PS-2 models...and then reverted to default=ON with PS3?    Interesting, in which case I agree with your characterization of this being "ridiculous."   Learn something new every day!

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@stan2004 posted:


So apparently MTH changed the Speed Control to default=OFF for some PS-2 models...and then reverted to default=ON with PS3?    Interesting, in which case I agree with your characterization of this being "ridiculous."   Learn something new every day!

Well I'm glad you're learning!  The speed control is not engaged on my PS2 lo-V subway engines when running conventional in the fashion I've stated above. Are they broken? Did changing the settings in DCS have some effect? Who knows, but my Lo-Vs start up every time without it when running in conventional in low voltage mode, requiring me to give extra power with my z-1000 transformer when running on inclines and tight curves. When I place them on my DCS track, they start up in command control with speed control activated and far higher voltage draws. Go figure.I guess I'm also continuing to learn something regarding my trains as well. I never knew this was apparently aberrant.

Last edited by Strap Hanger
@stan2004 posted:

ps2 5V engine with speed control default ON

I googled "MTH PS2 manual" and the first entry that popped up was this SD-45 which happens to be a PS2 5V version so 15-20 years ago.   The manual clearly states "Each time you shut down the engine completely, it will automatically turn speed control on."

So apparently MTH changed the Speed Control to default=OFF for some PS-2 models...and then reverted to default=ON with PS3?    Interesting, in which case I agree with your characterization of this being "ridiculous."   Learn something new every day!

1.  If that is from a PS-2 manual the language is the same as in the PS-3 manual I cited.  Defaults to ON (not OFF) when you turn the power off.  Or am I not understanding something?

2.  Also, I will try those scale speed tests.  The engine does seem to big down more with the additional cars attached and speed control ON.  Enough of a drag that the additional drag pulls the engine car off the rails slightly on a sharp 027 curve popping my circuit breaker.

John

Last edited by Craftech
@Craftech posted:

1.  If that is from a PS-2 manual the language is the same as in the PS-3 manual I cited.  Defaults to ON (not OFF) when you turn the power off.  Or am I not understanding something?

2.  Also, I will try those scale speed tests.  The engine does seem to big down more with the additional cars attached and speed control ON.  Enough of a drag that the additional drag pulls the engine car off the rails slightly on a sharp 027 curve popping my circuit breaker.

1. No you are not missing something.  Strap Hanger reports he has a PS2 engine that defaults to OFF which surprised me but it is what it is!   Since your engine defaults correctly per the manual, this was just an interesting side conversation.

2. There may be two (or more?) "things" going on here.

a. That the engine bogs down with "only" 3 cars is bugging me.  Apparently the KW itself has enough power.

Apparently you don't have any other similar PS2/PS3 engines?  By similar I mean a twin-engine diesel.  With speed-control ON, they should behave similarly in terms of speed vs. voltage.  It's often overlooked, but the reason the speed vs. voltage profile should be the same between PS2/PS3 engines is to consist PS2/PS3 engines in conventional mode with speed control ON.

If you do undertake some speed measurement experiments, be sure to measure the track voltage at the far end of the track (rather than at the transformer itself or at the single lockon).  The idea here is to rule out any track wiring issues.  So if the voltage drops substantially as the consist passes by the far end, that would be a good clue.  I appreciate that your other engines seem to operate "OK" (they run fast enough).  We can get into HOW the MTH speed control works down at the voltage/current detail but it gets technically boring rather quickly. 

b. Separately, I figure the 031 guideline is there for a reason albeit it may work on 027 under some circumstance.  That is, trying to qualify 027 operation by saying it works if only pulling less than 3 cars, or only if the traction tires are new, or only below certain speeds, or...well you get the idea.  To your point, I'm sure there's also something about the brand/version of track and how it interacts to lateral side-to-side forces with the wheel flanges going around curves; this is far above my pay grade.

So.  Presumably the engine operates OK by itself around the 027 layout and the speeds you desire. If the objective is to run the full consist on the existing track, it seems to me the idea would be to reduce the load since it's obviously the load force thru the engine's rear-coupler that pulls the engine off the rails.  So after double-checking the trailing cars for smooth rolling of the axles on their pin-point bearings and the like, it seems the next step would be to ballpark how much of a reduction in load would make it work.  In one alternative universe, you could remove the center -rail roller pickups and outer-rail axle wipers on one or more lighted cars and run a 2-wire tether between the cars to power the lights.

@Craftech posted:

Is there a difference with a DCS system set to "conventional" and a conventional setup with a postwar transformer?

If you mean different on the transformer side, then YES in capital letters!  By PW I assume you mean the generic design where a roller slides across transformer windings to change the output voltage.  The voltage output is a stepped-down version of the AC line voltage so it is "clean" and sinusoidal in shape.  By DCS system in conventional I assume you mean the so-called "Variable Channels" where the TIU generates the conventional track voltage.  The input to the Variable Channel is a clean 18V AC sinewave.  It then uses electronics to chop (mangle) the input to change the output voltage.

If you mean different on the engine side, then MAYBE.  You may be referring to the transformer compatibility table in MTH engine manuals.  But specific to the matter at hand, for PS2/PS3 engines the speed control behavior should be the same.  There are other features such as whistle triggering or smoke volume that may behave differently depending on pure vs. chopped track voltage.  Consider that modern MTH PS engines can also operate with DC and DCC track voltage.  Those two track voltage types are about as far apart as you can get...with the standard 60 Hz AC  (pure or chopped) somewhere in between!

Last edited by stan2004

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