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RC plane Project Part 7 & 8 - Rudder / Elevator Servos and Motor-Mount Test

Non Stream Link Motor Test 1 Depronmotortest1.wmv

Non Stream Link Rudder / Elevator installation & Motor Test  2 Depron Rudder/Elevator servos

Installation of Rudder and Elevator Servos..... and

Test of Motor Mount for Depron , not full power yet - as no multimeter was in circuit (max 10A before burnout ;-)

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Just noticed on the multimeter during propellor wind down - meter is showing 0.5A generated power. (albeit short lived).

You would probably find the polarity is reversed during that brief period. As the voltage across the fuse is very small this should not be a problem. If the fuse had blown then the zener diode would now be forward biased limiting the voltage to -0.6V to help protect your analog input.

In the Wild Thumper controller, an LM358 is used to amplify the signal and also protect the analog input since it's ouput is within 0-5V.

I have also soldered a Schottky Diode (SR506) directly across motor terminals too (it was recommended and supplied in the kit that came with my new 25A Graupner ESC) .

When I built Turbo Trike using a ducted aircraft engine I found that the vibration quickly loosened screws causing the prop to chew things! My suggestion is glue your screws with some thread lock. Failing that slap on a small blob of polymorph :P

Thanks for the tip - yes the screw holding the engine together are made from nylon !!! , so i have replaced them with metal ones and it goes real smooth now - i will posat video here with non-stream links shortly, the difference is amazing.

I had to insulate the poly in contact with the motor housing with some depron to shield the heat - works fine without meltdown, cool runnings.

BTW :- i am measuring the propellor current by monitoring the voltage across a fuse - it works fine, however i have a question what happens if the fuse blows? (by my calculation the voltage measuring circuit will still be live an sink the current - did i miss something?) prehaps i should put 2 fuses in 10A and 15A and monitor the 15A one (haha)

When the fuse blows you will get the full battery voltage accross the terminals. Use a voltage divider or a series resistor and zener diode to protect your analog input. Yes some current will still pass through but with a series resistor of at least 10K it will be small enough not to do any damage. The resistor combined with the capacitor work as an RC filter to help with noise and spikes. The capacitor can be removed or it's value changed to suit your requirements.

Did you have any specs with the motor? Normally they include a little chart with recommended props. Is it an apc slow fly you are using now? Note that some props can do with some balancing (often causes the woobeling).

Take a look at "watts-up". Nice thing's you hook up between the motor and the power source. It might be my pc speaker but there's a rattle somewhere when running the motor?

I took the motor out to upgrade the ESC and lo and behold one of the Motor screws was loose.......... so your pc speaker is ok....thanks..