Sydney STA

Sydney STA
Sydney STA fleet for layout

Wednesday, 7 January 2015

With a Little Help From My Friends

First of all, a Happy New Year to my regular blog readers.

The past 6 weeks have been busy finishing off the electronics on the first module. We had family and friends at Christmas and New Year and I wanted to show the layout with something that was operational.

Polarity changes
As written in the last post, I was able to get the Peco turnout motors wired and working correctly.  However, as the turnouts are electrofrog it will need to also include a switch to change the polarity of the turnout so that the track does not short circuit.
I used the Peco PL-13 Accessory Switch to change the polarity and followed the instructions as per below. The instructions were not clear as to which wires (positive or negative) to connect to each of the rails I assumed that depending on whether it was a left or right hand turnout it could be either positive or negative. 

Turnout Indicator lights
Another challenge was that I wanted to incorporate a control panel which includes LED lights for turnout indicators. The idea was that if I used a toggle switch to motorise the turnout it will also indicator the direction of the turnout: Red for turning and green for straight.

Not knowing where to start I found the following indicator light information on the Internet as a basis for wiring the LED lights.

By only using this diagram and after soldering 5 green and 5 red LEDS as well as the 1K resistors I found that some of the LEDS were always on or always off. I was stumped as to why they were not working.

With a Little Help From My Friends
Two of the people who viewed the layout over the holiday period such as my brother-in-law (who I didn't know was trained as a electrician) were electrically minded.

They viewed the wiring and were a great help in diagnosing where the problem may lie.

They also provided some useful hints and advice:
* A short tuition on how to use basic functions of a the multimeter (although I had one I didn't know how to use it)
* Determine whether current was flowing through the wires using the multimeter
* LEDs have a positive and negative legs so having determined this I found out that my wiring were incorrect for some of the LEDS and I had to undo and redo some of the LEDS.
* Test the LED lights before soldering using the multimeter
* Teach me how to make the wiring more neater and organised

If I feel up to it I may create a circuit diagram of the electronics for the first module.

The End Result
After correcting the LED wiring I found out that still some of the LEDs didn't work.

I rechecked all the LEDs again and then revisited the wiring of the Peco instructions of the PL-13 switch above and decided to remove the two wires that connect the track to the two connectors that were close together. I also ensured that the PL-13 switch was connected to negative rail  and also ensure that the connector shown in the indicator diagram was connected to the track with a negative as per the turnout indicator diagram

Finally, Presto it worked below is the video showing the workings of the indicator lights and turnout motors.