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Recent Posts
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RailPro Specific Help & Discussion / Re: Over Amp motor issue with LM-4S-G
« Last post by gregeusa on Today at 01:02:22 PM »Seems that one of your problems is that the motor is "spiking" short term current and trips the decoder.
Try adding a 1/2 ohm power resistor in series with the motor(s) and see if that works... common issue in large scale.
Greg
Try adding a 1/2 ohm power resistor in series with the motor(s) and see if that works... common issue in large scale.
Greg
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RailPro Specific Help & Discussion / Over Amp motor issue with LM-4S-G
« Last post by blwloco on Today at 10:01:07 AM »Hello RailPro forum! My name is Nick Bulgarino, and I have a model repair shop that installs dead rail systems. I am new to RailPro, and I am running into an issue with the motor control.
There are two issues I have: the first is low speed control; the second is over amping the circuit.
The locomotive, even if I change the start voltage, will not move until I reach 20% or higher. Then it'll jolt forward. I can bring the speed back down and control it, but that's not very prototypical. I am trying to figure out how to fix this, but the manual does not cover this issue.
The locomotive has a stall current of 3.4 amps. The LS-4S-G is advertised to handle up to 8 amps. I am getting an over current error when operating the engine under medium to long train lengths even after doing the Motor Full Load Current test. The test puts the motor current at 750mA to 850mA. That is well below the threshold I think. In order to operate the engine, I have to limit the top speed to 45%. This is too slow for most operations and lacks the power to pull a train up grade.
My question is what am I missing?
Thank you!
There are two issues I have: the first is low speed control; the second is over amping the circuit.
The locomotive, even if I change the start voltage, will not move until I reach 20% or higher. Then it'll jolt forward. I can bring the speed back down and control it, but that's not very prototypical. I am trying to figure out how to fix this, but the manual does not cover this issue.
The locomotive has a stall current of 3.4 amps. The LS-4S-G is advertised to handle up to 8 amps. I am getting an over current error when operating the engine under medium to long train lengths even after doing the Motor Full Load Current test. The test puts the motor current at 750mA to 850mA. That is well below the threshold I think. In order to operate the engine, I have to limit the top speed to 45%. This is too slow for most operations and lacks the power to pull a train up grade.
My question is what am I missing?
Thank you!
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Finished RailPro Installation Examples / Atlas O Scale SW8 / SW9 3R to 2R
« Last post by TJMac on July 12, 2026, 05:27:45 PM »Atlas O scale SW8/SW9 - Started life as a 3R from the early 2000s purchased used on the eBay.
- Removed all factory electronics
- Created speaker mount / grill to relocate added SoundTraxx 28mm speaker to the fuel tank
- Created a tray / mount for the LM-5S-G
- Built a wiring harness with Deans Micro plugs to make working on / repair easier
- Created pickup holders to use Northwest Short Line 1.7" brass pickups as these parts are not available from Atlas
- Used Northwest Short Line 2R conversion axles / wheels / gears
- Swapped incandescent headlight bulbs with LEDs
Currently working on fixing the pilots to make them more prototypical
- Removed all factory electronics
- Created speaker mount / grill to relocate added SoundTraxx 28mm speaker to the fuel tank
- Created a tray / mount for the LM-5S-G
- Built a wiring harness with Deans Micro plugs to make working on / repair easier
- Created pickup holders to use Northwest Short Line 1.7" brass pickups as these parts are not available from Atlas
- Used Northwest Short Line 2R conversion axles / wheels / gears
- Swapped incandescent headlight bulbs with LEDs
Currently working on fixing the pilots to make them more prototypical
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RailPro Specific Help & Discussion / Re: Where to buy RailPro
« Last post by sieggs1 on July 11, 2026, 10:56:21 AM »Hey All,
Anyone buy any RailPro equipment lately? I am looking for more LM-3S-21 decoders but it seems like only RailPro is stocking them these days. I don't really want to pay full price.
Sieggs
Anyone buy any RailPro equipment lately? I am looking for more LM-3S-21 decoders but it seems like only RailPro is stocking them these days. I don't really want to pay full price.
Sieggs
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RailPro Specific Help & Discussion / Re: Outputs for smoke units
« Last post by loco_man4449@hotmail.com on July 10, 2026, 10:19:46 AM »Thank you
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RailPro Specific Help & Discussion / Re: Outputs for smoke units
« Last post by gregeusa on July 06, 2026, 05:01:39 PM »The question you need to ask, what is the current limit on those outputs?
And you need to decide how you want to run the USAT smoke unit.
Depending on the configuration you can pull an amp with them... I doubt the RP module has that ability.
And you need to decide how you want to run the USAT smoke unit.
Depending on the configuration you can pull an amp with them... I doubt the RP module has that ability.
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Finished RailPro Installation Examples / MOVED: Outputs for smoke units
« Last post by G8B4Life on July 03, 2026, 04:34:51 AM »This topic has been moved to RailPro Specific Help & Discussion.
https://rpug.pdc.ca/index.php?topic=1822.0
https://rpug.pdc.ca/index.php?topic=1822.0
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RailPro Specific Help & Discussion / Outputs for smoke units
« Last post by loco_man4449@hotmail.com on July 02, 2026, 09:05:49 PM »I will be doing my first Rail Pro install. This is in a USA trains GP40 using a LM-5S-G. Can anyone tell me if outputs 7 and 8 can be turned on and off? I know smoke units take a lot of juice and shorten runs using batteries. Most likely will very rarely if ever use smoke, but would like to configure anyway.
Thanks in advance
Tom
Thanks in advance
Tom
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General Discussion / Sounds Stop Working
« Last post by rsmproductions on June 30, 2026, 06:49:33 PM »I've had an issue recently where i'll be running an engine with the chuff and other sounds with no issue. After awhile and especially it seems if I introduce another engine programmed in the same controller that the sounds stop functioning. Not sure what might be causing this. Anyone else had an issue like this?
Richard
Richard