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Shorting Circuiting Outdoor G-Scale

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  • Member since
    June 2015
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Shorting Circuiting Outdoor G-Scale
Posted by Dmilli55 on Sunday, June 21, 2015 1:47 PM

I'm having electrical issues with an outdoor G-scale train circuit. I'm using a simple power pack (MRC Tech II) supplying 14VDC and 13VA to a 72' long linear "circular" solid brass track and is connected in four locations around the track. The transformer is protected in an outdoor bar. I recently bought a used trolly to test the track and was working great for approximately three days of running hours and then the engine burnt out. I originally thought this was due to acquiring a used trolly, but after running a brand new Bachmann Anniversary Edition on the line, the locomotive alone shorts the circuit after about 5 minutes or so of running and sometimes on particular parts of the track. The transformer is about 15 years old but until this year was only used every Christmas season for a month to power an HO gauge line. I didn't know if the age of the transformer had anything to do with the shorts I'm getting. I took a multimeter out to measure the volts and amps and read 14.2V around the whole track. The amps I couldn't get a good read on, but it read 0.09A on average so I don't quite understand what that is about. The track has 4' radii curves and the engine seems to struggle a little on them. The track has been cleaned recently and passes by a waterfall which is properly spaced 4' from the edge. Can anyone help me figure out where these shortages and trips in the system is occurring whether its the transformer, curves, continuity problems, etc.? I believe the transformer is just too old and needs to be replaced but I don't want to make a $200-$400 mistake.

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Posted by ttrigg on Monday, June 22, 2015 4:29 PM

I am NOT a diagnostics expert by any means. You seem to have power evenly delivered to your engines. I would suspect that the trolly failure was due to previous damage and or dirt. Did you clean and service the trolly prior to running it? As for the "Bachmann Annie" my first thought is the she is not designed for that tight of a curve. She will fight to make the tight curve but the binding of the drive wheels in the curve will cause the motor to run hotter than designed. This could lead to total failure of the engine. "Annie's" prefer eight foot curves or larger. 

Tom Trigg

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Posted by ttrigg on Monday, June 22, 2015 6:42 PM

Ooops. Foot in mouth there. I re-read your post. You said Radius of 4 ft. I was thinking Diameter. Your 4 ft and my 8 ft are the same curves. Did you do any pre-servicing of the "Annie"? I'm at an empasse here, please excuse my prior error.

Tom Trigg

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Posted by tomgb on Monday, June 22, 2015 10:21 PM

I would guess that the problem here could likely be too little transformer.  At one time I used a MRC TrainPower 6200 on my early layout and it has two power output levels. One is rated 35VA max. and the other 27VA max. The MRC manual recommends using only the 35VA for LGB (read, large scale) trains and you indicate your transformer is only rated 13VA.  According to MRC, that’s too light a supply. It can cause the transformer to overheat and cut out and otherwise lead to motor problems as it tries to run without enough power delivered. And that doesn’t even take in the extra load of any additional cars pulled behind the engine, grades to climb, etc.

 

 

Perhaps others will chime in with specific numbers needed. Ultimately the general consensus seems to be to get a big power supply to start with if you think you may want to expand your layout someday,  but I suspect many of us have learned this after buying more than one power supply over the years.

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Posted by Dmilli55 on Tuesday, June 23, 2015 9:01 AM

ttrigg

 

Ooops. Foot in mouth there. I re-read your post. You said Radius of 4 ft. I was thinking Diameter. Your 4 ft and my 8 ft are the same curves. Did you do any pre-servicing of the "Annie"? I'm at an empasse here, please excuse my prior error.

tomgb

I would guess that the problem here could likely be too little transformer.  At one time I used a MRC TrainPower 6200 on my early layout and it has two power output levels. One is rated 35VA max. and the other 27VA max. The MRC manual recommends using only the 35VA for LGB (read, large scale) trains and you indicate your transformer is only rated 13VA.  According to MRC, that’s too light a supply. It can cause the transformer to overheat and cut out and otherwise lead to motor problems as it tries to run without enough power delivered. And that doesn’t even take in the extra load of any additional cars pulled behind the engine, grades to climb, etc.

 

 

Perhaps others will chime in with specific numbers needed. Ultimately the general consensus seems to be to get a big power supply to start with if you think you may want to expand your layout someday,  but I suspect many of us have learned this after buying more than one power supply over the years.

 

 

I did not do any preservice the "Annie" as it was brand new. I simply was testing out the thrack though and have only put less than 10 minutes of running time on her.

 

And yes the transformer is 13VA but I was told that this amperage would be plenty by a gentleman at the local hobby store. But I will say that the transformer does not seem to heat up at all. It seems to simply trigger the internal power short cut-off. To get it operational again the mains power switch must be swithed off and on again and the polarities switched back and forth to the original polarity. I don't know if that helps at all or not. Just trying to provide as much information as needed.

  • Member since
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Posted by Dmilli55 on Tuesday, June 23, 2015 9:06 AM

tomgb

I would guess that the problem here could likely be too little transformer.  At one time I used a MRC TrainPower 6200 on my early layout and it has two power output levels. One is rated 35VA max. and the other 27VA max. The MRC manual recommends using only the 35VA for LGB (read, large scale) trains and you indicate your transformer is only rated 13VA.  According to MRC, that’s too light a supply. It can cause the transformer to overheat and cut out and otherwise lead to motor problems as it tries to run without enough power delivered. And that doesn’t even take in the extra load of any additional cars pulled behind the engine, grades to climb, etc.

 

 

Perhaps others will chime in with specific numbers needed. Ultimately the general consensus seems to be to get a big power supply to start with if you think you may want to expand your layout someday,  but I suspect many of us have learned this after buying more than one power supply over the years.

 

 

     Yes the transformer is 13VA but the gentleman at the local hobby store informed me that would be suffice. I also have not serviced the "Annie" because I just was trying to continue testing the track as I only put approximately 10 minutes of running time on her between all of the controversy. But I will say about the transformer that there does not seem to be any heat generated when shorting occurs. The power mains switch must off and on and the polarity switch must be reversed and reversed again to the original polarity to regain power until shortening occurs again.

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  • From: North, San Diego Co., CA
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Posted by ttrigg on Tuesday, June 23, 2015 2:43 PM

Your transformer is shutting down to prevent fire damage. I would suggest that when you next go to your hobby shop, look at getting a larger transformer. One that exceeds the current needs of your empire. That will allow you to expand your layout without needing additional transformers. I have a shelf full of transformers that fail to meet the needs of my expansions. Putting lights in my buildings along with sound systems (honk-tonk music in the saloon, sounds of children playing in the park, station master announcements, etc.) Each addition takes a small bit more power and after a while it all adds up.

Tom Trigg

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