Eagle Tree RPM's, Magents or Photo ?

[mjdee14]

I'm in the process of getting and Eagle tree v3 from Santa....

What do you think is better for the Hurri...magnets or photo cell for the RPM sensor ?

And anyone have pics of how they mounted the sensor?

I thought the magnets might be better...any thoughts?


Mike

[Pinecone]

Brushless sensor.

You take the heat shrink off of one motor conenctor (ESC side) and solder a small guage wire (22 - 26 will work) and put a servo connector socket on it. Put a servo pin on the Eagle Tree sensor. Plug in and go.

Somewhere around here is info on the number of poles and the gear ratio.

[ukgroucho]

I always have bullet connectors between my ESC and motor, I just pull one apart and slide the stripped end of the brushless sensor wire into the female socket and then push the male in. Works a treat on every model I used my Eagletree on.

[mjdee14]

So in other words, don't even bother with the magnetic pick up?

Guess it's just good for car wheels..?


Mike

[ukgroucho]

Nope.. the magnetic and optical pickups are good for gassers also.

[Pinecone]

You can use the magnetic on outrunners to read the pole magnets.

Or use the optical or magnetic to read the main shaft (or main gear) directly.

But the brushless is easiest.

[bjosko]

When I got my EagleTree, the brushless sensor was out of stock, so I got the optical sensor.
You can barely se it here : https://www.helifreak.com/showthread.php?t=53836

I used a Body Retainer Bracket, part number 204697 at ReadyHeli, that i fasten to one of the screws that hold the main bearing, and a cabletie on the other end of the bracket, around the sensor, paint the half of my maingear white on the underside, and it works just fine.

But, if you are ready to do the mathematics, it is much easyer with the brushless sensor.

[Phoinix]

I mounted the optical sensor on the frame, above the main 61T gear. I painted a small white dot on the gear, let some 1mm gap inbetween the sensor and the gear, and it works perfectly, no 0 RPM dots on the recorder.

[mjdee14]

Eagletree V3 on order with both the brushless and optical sensor...( present from the daughter) so why not get both...

On the brushless sensor, do you have to set up the ratio in the word program? or do you just have to do the math every time? I also have the little lcd panel to use at the field, does that give actual rpm or the motor rpm and you still have to do the math?

The ET web site and manual do not explain it very well...

Also did a search on this forum and did not find any answers..

How are you guys using these..?

[Pinecone]

You tell it the gear ratio in the PC program and it does the calculations.

[nexgen]

Originally Posted by Pinecone

You can use the magnetic on outrunners to read the pole magnets.

Or use the optical or magnetic to read the main shaft (or main gear) directly.

But the brushless is easiest.

So for the magnetic sensor, the sensor can just read the magnets in the can of the motor? Just point the sensor at my outrunner and be done with it?

For the optical, from what I read here if I point it right at my main gear (make a contrasting color dot/line or something, my gear is red) then I will get the regular HS value without having to do any extra math?

I like the idea of the brushless sensor, I suppose the 2 stickpins on the wires idea is not so bad.

wanted to go with something that is not invasive to my existing setup as I want to be able to remove the unit easily

maybe I'll install both the brushless and one of the other ones and compare the results.