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I recently had a ERR cruise commander installed on  MTH Premier EP5 electric fail, and it was  replaced under the warranty.  However, I have learned that the motor current draw  of some MTH can motors is problematic in some cases.  I now have two Cruise Commander equipped MTH engines running and am worried about their future continued operation.  I like to run long trains slowly!  Any suggestions or experiences out there on this topic?  Phil

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@phil klopp posted:

I recently had a ERR cruise commander installed on  MTH Premier EP5 electric fail, and it was  replaced under the warranty.  However, I have learned that the motor current draw  of some MTH can motors is problematic in some cases.  I now have two Cruise Commander equipped MTH engines running and am worried about their future continued operation.  I like to run long trains slowly!  Any suggestions or experiences out there on this topic?  Phil

My guess is you have defective motors if you're burning up Cruise Commanders.  I've installed a ton of these, and short of other defects, I've never had one fail due to over-current.

An ammeter between the transformer and track will let you know if the motors are drawing too much current. Its rare for most engines running light to draw over two amps, most closer to one amp. As Pat points out the big Mabuchi 550s and 555s draw more than that but still less than the 8 amps the Cruise Commanders are rated for.

Pete

After the first Cruise commander was replaced and it had about an hours run time, I  got  advice concerning current draw of the motors.  Not knowing how to check this with a meter, I did realize that one of the motors got warm pretty quickly so I replaced it with a new one.  Then ran it  but the board failed again after about two hours run time.   At this point I learned from a reliable source that this was a known issue with some MTH motors.  Furthermore I do like to run long heavy trains  at low speed  and that may have contributed to my situation.   I did a second MTH conversion on a diesel that is running ok with no warm motors but  i am concerned  and this is  why I made this I will try and learn how to test motors with a meter and act accordingly. Thanks for the replies and let me know if you heard of the specific problem.

I've seen occasional bad motors, but usually they've been in Williams and Weaver steam.  The Mabuchi's that MTH and Lionel use in diesels have very low failure rates.  I've had a couple bad motors, but at least one of those was stalled and left to cook, can't blame the motor for that failure.

Truthfully, I've never heard anyone say that it's a known issue that MTH has bad motors.  The only modern stuff I know for sure have bad motors is the junky Canon motors that Lionel uses in their larger Legacy steam locomotives.

So who is the reliable source?  I have seen two PS-3 diesels with a motor imbalance that caused issues.  One motor would be dragged as they had dissimilar starting current.  Had to replace the tach drive motor.  So maybe that could have caused your issues.  I imagine that might mess up back EMF with parallel motors.

But I agree, this is not some major issue. G

GGG.  Believe me when I say my source is reliable.  I will reveal who it is in a private email.  Or feel free to call me.  Also, there has been a new development.

Here is a summary of events.

!  I installed the Cruise Commander in a MTH Premier EP5 and the Cruise Commander failed after a few months.  I operate using Legacy Cab 2 with the Cruise Commander programmed for TMCC. 18 Volt Lionel Bricks power the track on my layout.

2. The dealer I purchased it from replaced it under the warrenty.

3.  I reinstalled the new Cruise board in the same engine and using advice from my dealer I quickly realized one motor was getting hot after five minutes of use,  So I replaced that motor with a new one from MTH.

4.  I ran ran the EP5 for a half hour with a heavy train at slow speed.  The engine  suddenly stopped on its own and I could not get it to run again although it started up and sounds worked.  But it would not move.  I tried to get it to run over the next few days on both my layout and repair bench.   I opened it up, checked for obvious  pinched wires, etc.  My dealer said he could no longer honor the warrenty but would take a look at it and maybe it could be repaired.  An email today from him said he found nothing wrong and is returning it to me.

6.  I have one other ERR conversion (MTH Railking Alco diesel)  that has been running fine  for a few months now but I worry about a similar situations happening in  the future.

Phil Klopp

Is this a PS-1 converted?  Is motor current being used to drive anything else in the unit, lights, smoke?

I would take shell off and run so you can observe motors.  Does one start to spin while other drags?  If it does I would check the truck gearing and make sure no issues with free motor rotation.  Gear lash, split axle gear, broken side gear teeth, bent something can all affect.

It would also have been nice to observe current of this in motion.

But as stated there are a lot of conversions working fine, including one of yours.  G

Load is the enemy here. You really need to diagnose the issue as to why a motor overheated and got hot. Certainly could have been a bad motor, but not always is the motor to blame. Smooth operation of the gear train and wheels is just as important. When motor is removed, how does the truck roll? What condition are the gears in? When motor is installed, can you rotate the flywheel by hand smoothly in both directions? Any binding, or jamming, can result in a stall, even if only for a split second, and that results in heat, as the motor is trying to fight through the added resistance. To say MTH motors are problematic, is a cop out IMO. Your EP5 is equipped with RS385’s. All the major manufacturers use these motors almost unilaterally now. Yes, sometimes the RS385’s can go bad on their own, but 75% of the time, there’s also an underlying cause that kills the motor, or makes it overheat…..

Pat

@harmonyards posted:

I’ve never heard of MTH dual motor diesels & electrics being problematic with amp draw. Most if not all use identical motors to Lionel. Maybe getting confused with older Williams, or Weavers? Those have some crazy amp hungry motors.

Pat

I have to concur with Pat on this one. I have never had a modern diesel that was not an earlier Williams, or Weaver had any amperage draw problems at all.

@harmonyards posted:

Load is the enemy here. You really need to diagnose the issue as to why a motor overheated and got hot. Certainly could have been a bad motor, but not always is the motor to blame. Smooth operation of the gear train and wheels is just as important. When motor is removed, how does the truck roll? What condition are the gears in? When motor is installed, can you rotate the flywheel by hand smoothly in both directions? Any binding, or jamming, can result in a stall, even if only for a split second, and that results in heat, as the motor is trying to fight through the added resistance. To say MTH motors are problematic, is a cop out IMO. Your EP5 is equipped with RS385’s. All the major manufacturers use these motors almost unilaterally now. Yes, sometimes the RS385’s can go bad on their own, but 75% of the time, there’s also an underlying cause that kills the motor, or makes it overheat…..

Pat

I would have to also chime in with the fact, if you’re running a long train at slow speed, you have to make sure everything in that consist rolls freely. As in the case with Lionel subway, Trains, the cars are quite heavy and if you don’t keep the brass bearings lubricated, the power car does get quite hot. Just like in real railroading it’s all about the lubrication

This is a very interesting thread. I'm not sure if anyone knows this but Mr. Klopp here was probably one of the first to perform and document a TMCC conversion way back in the 90s. I believe it was in CTT if my memory serves me.

In any case, it would be interesting to know what component failed. I have my suspicions lately about component quality especially in the realm of hobby goods. It would also be interesting to know the vintage of the ERR CC. The most likely component to fail is one of the H bridge mosfets which would take the brunt of an overload or dead short in the motor(s). Heat is the killer of these (current X internal drain to source resistance) so a marginal device would be more likely to fail even in normal conditions. When I install my CCs I take care to have a nice thermal path for the heat sink. I will Dremel out a nice patch in a frame to match the base of the CC's heat sink and use heat sink grease to help with heat flow into more metal.

I've had nearly a hundred MTH engines in O scale and G, and never changed a single motor.

I've had issues of binding from loose ballast getting inside and even shorting a few axles. Yet no motor problems.

I found out that a second hand MTH 1 gauge engine with issues, actually had a screw dropped inside a truck causing it to bind. Once removed, that motor still works to this day.

I almost always run large trains. I match the overall train weight to have enough power to pull each train.

I have a feeling that some posting, might be abusing their equipment.

When I run G scale outside, the sun adds heat to each engine. So, I make sure they aren't overburdened with too heavy a train up the 2% climb.

Try pulling your train cars by hand, to see what they have to endure on your RR hill climbs. You may have a better understanding, of what you're asking them to do. Always run extra power and help them have a better chance of survival running for long stretches.

If your layout has areas that the power dips, I bet the engine will have to work harder than you expect.

Last edited by Engineer-Joe

I finally broke down, and using UTube easily figured out how to measure the amp draw of motors!  Really pretty simple!

I tested my Ps2 MTH EP 5 using a DC  HO transformer at 12 volts with no load.  Engine was on a test stand with no load.  The brand new MTH motor worked well at around a 2  amp draw.  Stall more than doubled the amps.   The other older motor drew about 3 amps doing the same tesr which doubled when stalling.  I then wired the two motors together in series and running amps and stall amps doubled.  

My plan here is to replace the other motor, using conductive grease and grind away the paint when mounting the Commander to the frame.  Then I will begin running some tests with long and short trains with the engine shells removed so I can easily monitor how long it takes for motors to warm up.  I will post my results in the next week or two.  

Finally, thanks to all of you for the helpful suggestions.  I will let others know if I can figure out why I was wrong in thinking the last cruise commander had failed and my dealer found it to be ok?  And thanks, Norm for your comments where back in the 1990's beginning when I had my Hobby Shop using my dealer status to place command boards in many postwar engines!    Phil Klopp

Phil, running without a load, 2 amps is WAY TOO MUCH CURRENT for a good Mabuchi RS3xx motor to draw.

For example, here's a PS/3 RS3 locomotive running at 55 scale MPH on the rollers.  That's two motors and sound, the current is 0.57 amps total from the transformer.  We're splitting that between two motors and sound.

  20240303_15350320240303_153520

Here's an RS365 from my parts box I use for motor tests.  I put 12VDC on it, and it draws 0.159 amps.  FWIW, it's stall current is over 2 amps, my current limiting was set at 2 amps and it went into current limiting when I stopped the rotation at 12VDC.  Note that 12VDC is the full voltage rating of the motor.

 

Bottom line is, those motors drawing amps have a major problem.  I'd suspect a problem with the power trucks, hard to imagine two motors going bad.

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Another thing to do that you can use as a sacrificial lamb instead of possibly killing a Cruise Commander, is to temporarily wire up a bridge rectifier to run both motors forward. This will let you test & observe mechanicals before ever hooking up the expensive Cruise Commander……..Every locomotive I build gets a bridge rectifier test trip around the layout for a good while before I commit to hooking up the Cruise Commander……..If something’s going to pop, let it be the 79 cent bridge rectifier ……

Pat

Phil, Something not right with your test.  Also, motors are wired in parallel which is highest amperage condition as the effective resistance is halved.  If you put two motors in series, the resistance to the power supply is additive and less current draw.  Each motor drops halve the voltage.  Having your amperage double with series motors is not right.

If you have a variable power supply (DC) raise voltage slowly and see when motor starts spinning.  Should be pretty low voltage.  Current low to0.  Make sure the other motor has same starting voltage for rotation.  This means they would be pretty balanced.  G

Good advice from both of you.  Good news too, is that I erred on my motor amp test.  Each of my two motors results rinning with 12VDC shows reading under 1/2 amp.  I feel better.  I got parallel and series mixed up and have better learned how to read my meter  when testing amps.  To All of you gentlemen who must have degrees in electrical engineering, a big thank you.  Phil Klopp

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