# Non DCC magnetically controlled lighting



## OilValleyRy (Oct 3, 2021)

This is an update/correction in regards to a few topics where I’ve referenced using reed switches and magnets to illuminate cabooses, passenger cars, vehicles, etc.

While reed switches indeed work, they require a constantly applied magnet or the reed switch returns to a default open position (off).
I thought there was a type of switch that magnetically locks in a closed or open position… allowing for the magnet to be removed and the light remain on (i.e. using a magnetic wand) until an opposite magnetic pole is applied.

*THERE IS…*

The component that does this is called a Hall Effect Sensor, sometimes called a Field Effect Sensor.
So that is what I’ll be using myself and recommending. They’re a bit more expensive than reed switches however, average about $6 each.


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## wvgca (Jan 21, 2013)

you can also get reed switches that will lock in an on position, look for latching reed switches , but they are about ten dollars each or so ..


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## traction fan (Oct 5, 2014)

OilValleyRy said:


> This is an update/correction in regards to a few topics where I’ve referenced using reed switches and magnets to illuminate cabooses, passenger cars, vehicles, etc.
> 
> While reed switches indeed work, they require a constantly applied magnet or the reed switch returns to a default open position (off).
> I thought there was a type of switch that magnetically locks in a closed or open position… allowing for the magnet to be removed and the light remain on (i.e. using a magnetic wand) until an opposite magnetic pole is applied.
> ...


OilValleyRy;

Not all hall effect sensors are latching as you suggest. I repaired machines that used Hall effect sensors, and they turned off the minute the magnet moved away. The ones I dealt with were also sometimes finicky. You had to practically rub the magnet against the sensor to trigger it.

Traction Fan 🙂


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## MichaelE (Mar 7, 2018)

I've experienced some contact bounce when a magnet is rapidly passed over them. My coil operated semaphores would sometimes activate twice as the train passed over the switch.

I also experienced this contact bounce using relays for the same application.

It didn't happen every time, but enough to be an annoyance when the semaphores were not set correctly because of this problem.


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## wvgca (Jan 21, 2013)

that is easy to rectify with a simple contact debounce circuit [ basically the same for reed, hall effect, sliding contact type switches] and is very easy to integrate to these types of circuits .. even a simple resistor / capacitor circuit will work .. it doesn't have to be fancy to work ..
see image ..


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