[ScorpiusWireless]

Hi Guys, 
   The motor analyser didn’t quite work out using BEMF but we still developed a tacho.
Here it is. 
It plugs directly into either data port.

   

A nice easy unobtrusive install.

   

[Kevan]

Would that still work if it was stuck under the chassis of a car where there isn't a hole for the motor?

...if so could that be made into a portable battery powered standalone unit for scrutineers and proxy organisers?

[ScorpiusWireless]

For closed can motors the white marker could be placed outside the can on the rotating shaft.
Yes a portable battery powered unit could be used.

[Kevan]

So does it need to see movement?

[ScorpiusWireless]

Hi Kev,

There’s 2 photo sensors in the unit. They are designed to detect reflective light. Hence we need a white or reflective surface.
I just use a little white nail polish.
Then hot glue the tacho on the motor directly over the reflective point. Then you just need to plug it into one of the data ports. The default firmware for Data Port 2 is the tacho. So you won’t even need to configure anything.

You’ll need a Scorpius dongle and free software to see your revs on your PC. We will also add it to the OLED screen which be handy, and of course very cool ….   

Add some paint.

   

Now add the sensor.

   

And below the reflective photo sensor. 

   

Plug it in. That’s it.

Here’s the pulse:

https://youtube.com/shorts/AdL5UnjxvEQ?s...aj1Y7G5ycy


So instead of using the planned hall sensor we just swapped to a light sensor. Job done.