EVERY track powered electric train owner should have THIS.

Started by Joe Satnik, December 10, 2008, 11:38:44 AM

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Joe Satnik

Dear All,

Every track powered electric train owner should have a test lamp made out of an 1156 automotive tail lamp (bulb) with one test lead (wire) soldered to the tip, and the other test lead soldered to the metal case of the bulb.

If you cut an "alligator clip style jumper lead" in half, you will have two test leads with an alligator clip on each end.  Very handy. 

This 1156 test lamp has 2 functions:

1.) It's a crude voltage indicator (brighter light = higher voltage),

and most importantly,

2.) It provides a stationary electrical "load" to "exercise" your power pack and track connections. 

Your moving load, is of course, your locomotive. 

If you clip the lamp leads to your volt-meter leads, you would get an "under load" voltage reading on your volt-meter, which is much more useful than a "no load" voltage reading while troubleshooting pesky track power problems. 

For example:

1.) Take all locos and cars off the track. 

2.) Split the first track-to-track connection just to the right of the power pack. (This assumes you have an oval track.) 

3.) Turn the power pack on and measure the voltage (test lamp clipped on to volt-meter leads) as close to the power pack output as possible. 

4.) Move the leads (left) down the track away from the power pack, measuring the voltage across the two rails at every track section. 

5.) Slightly move (flex) the rail connectors between the previous section and the one you are now measuring.  If the voltage drops considerably, or jumps all over the place, you have just flexed a bad connection.

6.) Repair the bad connections. (A gentle squeeze with a pair of pliers on a loose rail connector often works...Careful, don't smash the connector).

7.) Move down the line testing and repairing all bad connections.  When finished, re-connect your (split) oval. 

Voltmeter readings are nice, but using the brightness of the lamp as a crude voltage indicator is often good enough for troubleshooting track connections.   

Hope this helps.

Sincerely,

Joe Satnik     
If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

NelsOn-30

Joe & All

Thank you for a very informative tutorial.

An automotive test lamp, (looks like a screwdriver and has a pointed end, a lamp in the handle and a single clip terminated wire lead), will provide the same functions for anyone that is "do-it-yourself" challenged.

A volt meter, or a multi meter on the appropriate voltage scale, is very useful tool for locating open circuits. The meter (analog or digital) operates by taking a very small current from the host circuit.

A resistive open happens when "touch connectors"   (rail joiners) become resistive due to corrosion.

The voltage drop across a faulty connector is proportionate to the current flowing in the connection.

If you haven't already figured it out the volt meter by itself draws so little current through a resistance that it will not register a voltage change.

Loading a circuit will create a current flow that will reduce voltages across resistive connections and these voltage drops are now apparent using a volt meter.

If you are still confused you are now confused at a higher level, just ask as there is a lot of help on this board.
Nelson

Notka Lake Logging & Navigation RR

Joe Satnik

Dear Nelson,

You're welcome and thanks for the compliment. 

Your additional explanations complement my tutorial nicely. 

I wanted a larger lamp for more current draw (thus more effect) than the automotive test lamp.

I have a background in electronics, so yes, I am confused at a much higher level..

Sincerely,

Joe Satnik

If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

Yampa Bob

Being somewhat lazy, I let my "Tracker" check the rails, either by hand or pushed ahead of a locomotive.  The grain of wheat bulb is very sensitive, I use it mostly to locate dirty track sections.


I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.