Indication and alarm of Turnout status
Posted: Thu Nov 25, 2021 9:43 am
After many months of ‘carpentry’ eradicating the termites and rebuilding my train room, I decided a bit of electronics would be a change and maybe get the grey cells working.
The new track arrangement in my train storage room (called Termite) has 4 sidings leading off the reverse loops. If a turnout is left open to the siding, and a train run in around the reverse loop the train can finish up in the buffers of the siding, or worse, hitting other trains in the siding.
Of course I myself would never leave the turnouts set for a siding , but maybe visitors or my grandsons might.
So my first idea was to just put an indicator light on each turnout with a bright red LED.
Then I thought an audible alarm would be useful to remind operators outside the room not to let their train enter.
And then after a near miss, I realised that the wagon storage drawer could be left fouling the mainlines. So another alarm was called for.
To detect the state of the turnouts, I used a photo-detector. It just requires 2 resistors and the LED in addition to the photo-detector.
A piece of plastic glued to each turnout tie-bar slides in the optical slot to block the beam and turn on the red LED.
An alarm is also triggered by each turnout and sent to a common alarm board which uses a picaxe (micro computer) to sound the alarm softly for about 20 seconds and then go loud until all alarms are reset.
There is also a Light Dependent Resistor (LDR) to detect when the drawer is fouling the main line and it connects to the alarm.
And a video of the operation might be easier to follow..
The new track arrangement in my train storage room (called Termite) has 4 sidings leading off the reverse loops. If a turnout is left open to the siding, and a train run in around the reverse loop the train can finish up in the buffers of the siding, or worse, hitting other trains in the siding.
Of course I myself would never leave the turnouts set for a siding , but maybe visitors or my grandsons might.
So my first idea was to just put an indicator light on each turnout with a bright red LED.
Then I thought an audible alarm would be useful to remind operators outside the room not to let their train enter.
And then after a near miss, I realised that the wagon storage drawer could be left fouling the mainlines. So another alarm was called for.
To detect the state of the turnouts, I used a photo-detector. It just requires 2 resistors and the LED in addition to the photo-detector.
A piece of plastic glued to each turnout tie-bar slides in the optical slot to block the beam and turn on the red LED.
An alarm is also triggered by each turnout and sent to a common alarm board which uses a picaxe (micro computer) to sound the alarm softly for about 20 seconds and then go loud until all alarms are reset.
There is also a Light Dependent Resistor (LDR) to detect when the drawer is fouling the main line and it connects to the alarm.
And a video of the operation might be easier to follow..