30-1608-1, bought used, no chrono or mileage readings, surges initially, not in a jerky fashion, but noticeably speeding up and slowing down. After ~ 5 mins, it appears to stop, and maintain set speed. All other features that can be accessed in conventional seem to work fine. Any ideas what would cause this?
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So you're running it in conventional? Or with the DCS remote?
Conventional. The DCS Explorer only holds 3 locos, it’s full up, and you can’t delete one and add another, afaik.
Hm. That's interesting. The first thing I would do is grab my multimeter and see if the track voltage is varying. You can confirm this by connecting a light to the track as well. Or reading the output on the transformer if it has that. What transformer are you using? Something is wrong in the transformer if the voltage is fluctuating a lot. We'll figure out what if we find out that could be the issue.
If your voltage is steady, I would say try a factory reset? I don't know if PS3 locos use a speed controller in conventional mode or runs on straight voltage. Somebody else here might know better than me.
We'll figure it out one way or another.
How big is your loop of track? You could be experiencing voltage drop from a large loop.
It’s the only engine doing this, so, pretty sure it’s neither track nor transformer. Thanks for the thoughts. Will try a factory reset.
No difference after reset.
How comfortable are you with taking the engine apart to take a look inside?
I wonder if you need some oil/grease. It almost seems like that might be it.
Sorry I haven't helped yet. I'm still on the troubleshooting learning curve.
Been there, done that, got the tee shirt. I’m wondering if it’s the timing tape on the flywheel. Not a big fan of pulling off the shell.
Just not understanding why it seems to smooth out?
The timing tape might be smudged but that doesn't explain why is seems to improve after a bit. Do the PS3 locomotives have momentum settings?
@Mark V. Spadaro it could be as Billy is thinking some sort of issue with the momentum control. It could also be something more basic electrically. You might also consider measuring the current flowing to the loco and note if that changes corresponding to the speed changes. This may be informative.
If you don't have an ammeter to measure the current, attaching a incandescent bulb lighted car with an unconditioned power supply (no internal capacitor in the car) and observe if the light intensity changes with the speed changes. Noting whether the brightness or current increases proportionally or inversely with speed may help narrow down the issue.
What type of transformer are you using? I have one Z-1000 that will have varying voltage (up and down) as I turn the control handle. When I reach the speed I want, I let the handle sit and the varying voltage settles down. The fix for this throttle issue is to take the cover off the controller and spray the potentiometer with contact cleaner. Solves the problem for some time and then the procedure needs to be repeated.
Ron
@RON ARNDT 091718 If it's the transformer, wouldn't all the locomotives have the same issue?
SteveH - wouldn’t what you’re suggesting pertain to all locos, too?
Mark, since you've already determined that your other engines, track and transformer are working as expected, my suggestion is relevant to this particular situation of unexpected speed changes. The goal being to narrow down whether the 30-1608-1 locomotive's changing speed issue is related to an intermittent voltage drop and where it may be occurring (possibly inside it, like a loose, cold soldered, or oxidized connection) or if the issue is due to an intermittent increase in current draw caused by something in the locomotive. As has already been suggested it could very well be an electronics control setting, but MTH systems are not my forte, just general electronics troubleshooting. If no relevant control setting or feature can be identified as the cause, my suggestion may be a good next step to help you decide whether you want to remove the shell to investigate further.
Ok thanx, Steve. I dragged an old MTH caboose behind, and watched the caboose’s lighting with speed changes. They were appropriately dimming and brightening with throttle changes. I hope this is what you meant.
Man this one's got me stumped!! Mostly because of my lack of MTH electronics.
Could a resistor be changing value as it heats up?? I thought that was something only germanium resistors did.
@Mark V. Spadaro is it a specific spot on the layout this happens?
About the PS3 Speed Control, after reading the Manual, Link here: https://mthtrains.com/sites/de...ction/30st13330i.pdf
On page 12 it discusses the Speed Control Feature which is located in the Conventional AC Operation section. One thing of note, is that after this train has been powered down for a while, this feature automatically resets to ON.
I'm guessing you already know this, but, it may be worth mentioning that it's normal for many locos to slow down through curves and up grades, then speed up again on straights, etc... if they don't have a Speed Control or similar feature. So, including some other possibilities, the Speed Control circuitry may or may not be malfunctioning.
Before going any further with this discussion, I want to check my inferences from the stated problem. To give it a simple name, let's call the final speed that the train eventually settles into at a given transformer throttle position Normal Speed. At this given set (unchanging) throttle position, is the Loco:
sometimes going slower than “Normal Speed” and
sometimes going faster than “Normal Speed”
before it settles at that final “Normal Speed” ?
@Mark V. Spadaro posted:Conventional. The DCS Explorer only holds 3 locos, it’s full up, and you can’t delete one and add another, afaik.
Sure you can. Just delete one of the locomotives in the app and add the N&W 0-8-0 in its place.
Mark,
Could be a problem with the motor causing erratic voltages. Could include a loose wire going to the motor, bearing on the armature shaft failing or a bad solder joint on the motor power leads. My suggestion would be to remove the locomotive from the track and power up the motor by itself (DC). Vary the applied voltage and see what happens. Let it run at varying voltages for about 5 minutes each setting and see what happens.
Bruce
Sorry I haven’t replied to others; have my twin 1 y/o in the house!
I don’t know where to begin, but I want to thank Lou1985 for his information about adding a loco to dcs explorer. I was able to delete a loco and add the Norfolk and Western 080 and, under DCS, it is running rocksteady no variation whatsoever. I’ve tried it at several different speeds and there is no behavior like it was showing in conventional. Thanks to all respondents, and does this lead anyone to think of a cause of the surging in conventional?
Glad you got somewhere with it!
But now I'm even more confused about it would run nice with DCS but not conventional haha
You and me both!
@Mark V. Spadaro posted:You and me both!
Well if there's a place that can answer it, it's this place. But most importantly, you can run trains now haha
Touché
@Mark V. Spadaro posted:Conventional. The DCS Explorer only holds 3 locos, it’s full up, and you can’t delete one and add another, afaik.
Of course you can! Choose or Add an Engine, when you choose it, you can delete it.
GRJ - Any thoughts as to why it would run steady in DCS and surging in conventional?
My first thought is something on the wheels/pickups/track. Command operation has a generous reserve of power since the track voltage is at max, conventional requires closer to the track voltage supplied for steady operation.
@Mark V. Spadaro posted:30-1608-1, bought used, no chrono or mileage readings, surges initially, not in a jerky fashion, but noticeably speeding up and slowing down. After ~ 5 mins, it appears to stop, and maintain set speed.
1. By "surges initially," does this mean each and every time you move the engine after it has come to a stop? Or, does initially mean the first time you run the engine in an operating session after the engine was unused/unpowered overnight? Or something in between...like initially after the engine is allowed to shutdown by removing track power...but power is immediately re-applied after only a few seconds.
2. During the 5 minute surging, is the speed varying between the "set speed" and something faster? In other words, if the conventional throttle is set to what ultimately settles out to, say, 25 sMPH are the variations always above 25 sMPH? Or does the speeding up and slowing down vary above and below 25 sMPH?
3. During surging, do the chuffing sounds also speed up and slow down proportionally? Or is it just the engine speed that changes and the chuffing cadence remains constant?
4. Finally, and I don't know if practical to do so, but do you have another similar MTH engine and can it be run together on the same track perhaps initially half way around the loop from each other? The idea is to determine if the engine is running at the "correct" conventional speed for a given throttle (voltage) setting. Similar MTH PS2/3 engines have the same speed vs. voltage profile (allows running conventional consists for example).
I figure you might already know the answers to above...not trying to set you on a snipe hunt!
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