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Question for you electrical engineers

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  • Member since
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  • From: Lake Worth FL
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Posted by phillyreading on Tuesday, March 6, 2007 1:54 PM

Like Bob mentions it is hard to find a high resistance joint or connection as it won't show up even with a digital multimeter.  Maybe it is dirty connections at the pins or track, never the less you end up with problems. 

When using older track it is best to use more lockons than what might be recommended in the book.

Lee F.

Interested in southest Pennsylvania railroads; Reading & Northern, Reading Company, Reading Lines, Philadelphia & Reading.
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Posted by ADCX Rob on Tuesday, March 6, 2007 12:51 PM
 otftch wrote:

I need someone to help me understand this.If you take five straight tracks and hook them together,hook up a lockon and wire to a transformer the train will run.Now hook a up a circle of track in the same way and a train will run. How come if a train comes to bad joint (on the center rail)of the circle  does the train stop ? Why doesn't the current flow around the track to the other end of the track with the bad joint ? I've ran into this more than once where the other end of the bad track has a good connection.Fix the bad connection and all is well.I'm not a beginner wiring track and fixing problems but people don't understand my explanation,when I tell them MAGIC  ! I'm not talking about an e-unit cycling.The engine is totally dead on that section of track.Push it by hand to the next section and it runs.

                                                                                         Ed

You have two or more bad joints, not just one.  The dead spot is obviously in between two faults.

Rob 

Rob

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Posted by lionelsoni on Tuesday, March 6, 2007 9:36 AM
You can find a completely open joint with a lamp or even a voltmeter; but a high-resistance joint won't show up until you try to draw significant current through it.

Bob Nelson

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Posted by spikejones52002 on Tuesday, March 6, 2007 9:24 AM

I did this for my 2 rail equiptment.

From what I remember most three rail equiptment have a front and back center rail wiper.

Make up a test car. spit the power wiper front and back. 

I connected a lamp from the power pick up to each wheel, and a lamp between the two power pickups.

If you can do some extra wiring. Install a lamp between each wheel set front to back.

Now apply power and push the car around the track. You will see when the lamps drop out or flicker.

I know it is much easer on two rail. I can find an open joint during the day by watching the lamps change.

At night I can seen poor joint connection by lamp brightness.

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Posted by jimhaleyscomet on Tuesday, March 6, 2007 9:06 AM

O.K. Ed,

I am now stumped....ideas anyone?

Jim H 

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Posted by cnw1995 on Tuesday, March 6, 2007 9:04 AM
Wow, Jim and Ed, I've just had exactly that circumstance - the train crossed a track connection and suddenly slowed down. Everything looked fine. I ran another lockon to the other side of the connection and it's fine again. I'll have to remember to test the connection this way first. Thanks!

Doug Murphy 'We few, we happy few, we band of brothers...' Henry V.

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Posted by otftch on Monday, March 5, 2007 8:35 PM

Jim H,

           I use a small screwdriver to do the same thing.I even checked the other end of the bad track with a ohmmeter.

                                                                   Ed

"Thou must maintaineth thy airspeed lest the ground reach up and smite thee."
  • Member since
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Question for you electrical engineers
Posted by otftch on Monday, March 5, 2007 8:00 PM

I need someone to help me understand this.If you take five straight tracks and hook them together,hook up a lockon and wire to a transformer the train will run.Now hook a up a circle of track in the same way and a train will run. How come if a train comes to bad joint (on the center rail)of the circle  does the train stop ? Why doesn't the current flow around the track to the other end of the track with the bad joint ? I've ran into this more than once where the other end of the bad track has a good connection.Fix the bad connection and all is well.I'm not a beginner wiring track and fixing problems but people don't understand my explanation,when I tell them MAGIC  ! I'm not talking about an e-unit cycling.The engine is totally dead on that section of track.Push it by hand to the next section and it runs.

                                                                                         Ed

"Thou must maintaineth thy airspeed lest the ground reach up and smite thee."

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