Spirit System
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Governor engaged RPM too high
https://www.spirit-system.com/phpBB3/viewtopic.php?f=20&t=3138
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Author:  George Baker [ Mon 04. Feb 2019 23:57:09 ]
Post subject:  Governor engaged RPM too high

Here's what I have....

Spirit Pro
Spartan RPM sensor on Zenoah gas engine flywheel; 1 magnet
Sensor is powered by Spirit AUX 1 plug; 7.8-8.2V (throttle servo gets battery voltage from servo power board; its signal wire is also connected to AUX 1 plug)
RPM reading in Spirit RPM Sensor Meter is steady and accurate
Throttle freaquency 333Hz - MKS HBL380 servo - Throttle direction is normal in TX and reversed in Spirit
Servo linkage almost 1:1 ratio horn to throttle arm (12.5mm to 10mm)
Throttle range setting so throttle plate is at engine idle with transmitter throttle channel at 12 (range 0-100)
Throttle plate is just full open at 100
Normal throttle curve 3 point curve 12-15-100 started with 12-30-100
Throttle hold flat 12
Idle up 1, 65 flat line
Idle up 2, 75 flat line
Sensing divider 1
Gear ratio 6.85 actual gear ratio 6.875
Max head speed set at 2200
Spoolup Rate Fast
Spoolup Rampup 100 us
governor response 5
Holding Performance 2
Holding Limit 80%
I shut off the engine with remote control kill switch not by closing the throttle all the way. That is why there is no throttle setting below 12 (idle speed). I do not use soft start so fast rate and 100 us rampup for quick bailout if necessary.

What is happening. Everything seems to work right except the governor does not govern to 1430 RPM in IU 1 it goes to what I think is 2200 RPM. I'm getting the governor engauged message in the log so that is right. I can tell the governor is engauging at 50% like its supposed to but the speed always goes to what I think is 2200. Its definately too fast. My first IU 1 setting was 80 flat for a target speed of about 1800 but that was the same result as the 65 IU 1 setting; about 2200 RPM.

I'm stumped. Everything seems to work right except it doesn't work.

Author:  George Baker [ Tue 05. Feb 2019 6:43:48 ]
Post subject:  Re: Governor engaged RPM too high

More information:

I found a post on this forum where the person had the same problem as I am having. He "re-flashed" the firmware and the problem went away.
http://www.spirit-system.com/phpBB3/vie ... =20&t=2486

So; I downloaded the latest firmware again; this time I used Chrome since it seems more compatible with your website and doesn't require changing the filename extension; and I re-installed the firmware over the top of the same latest version. I did not reset to default and set up again from scratch. I used a USB cable instead of WiFi this time.

I changed the throttle range settings. Remember I had to reverse the servo in governor/throttle settings. So to set the minimum (throttle closed) position I had to adjust the Max numbers to 1920 us (throttle fully closed). To set the throttle open position I had to adjust the Min numbers to 1240 us (throttle fully open).

I still have the same throttle curves but I bumped the normal curve to 12-25-100

There was another post where the person had the same fear I have (had) where if you set Spirit throttle range all the way down to 0 (zero) the governor could possibly stop the engine in flight but you re-assured the person that won't happen so I now have the throttle range adjustment from fully closed to fully open as recommended.

I will run a test again tomorrow (or when weather permits) and see if that has made any difference. I suppose if I had to I would reset the Spirit to factory defaults; re-install the firmware; re-set to factory defaults again and then setup from scratch; but I hope not to have to do that.

I love your response to the first person who had this problem; "This is really strange"
I had the same response!

Author:  ZeXx86 [ Tue 05. Feb 2019 11:18:51 ]
Post subject:  Re: Governor engaged RPM too high

Hello,

I very highly recommend to always use Spirit spoolup procedure. Not normal throttle curve. This will ensure the RPM will be where you will set TC.
This mean to set throttle for idling - usually around 10% and then engage the Idle 1/2.

With normal throttle curve pilot can easily overshoot the requested value or forget to set right Bank.

Author:  George Baker [ Tue 05. Feb 2019 15:25:51 ]
Post subject:  Re: Governor engaged RPM too high

My other gas helicopter does not have a governor; no soft start. I have at least 1 electric helicopter the soft start doesn't work very good. So; to make double darn sure I don't execute a mental error and pop the throttle hold off with it in idle up 1 on the wrong three thousand dollar helicopter I don't ever use soft start. Not on any of my 6 helicopters; not on the simulator; never. Every startup is the same on every helicopter and in the simulator. Normal mode; easy increase to idle up speed and then change to idle up 1.

In the case with this helicopter, as is with all of my helicopters, the engine RPM in normal mode after lift off is always a little slower or exactly the same as idle up 1 when I change to idle up 1 (thus the 12-25-100 throttle curve). This should not be a problem as the Spirit is going to see the same throttle channel value from the transmitter regardless of any switch positions.

I will test again in a little while and let you know how it goes.

Author:  George Baker [ Tue 05. Feb 2019 17:56:16 ]
Post subject:  Re: Governor engaged RPM too high

Okay; I tested again and the governor does not function. Instead of the 1500 RPM headspeed I have it set to I get 2138 RPM (measured with Spirit app). The governor doesn't work. Everything is set correctly and it doesn't work.

But; now it doesn't matter because the Zenoah clutch in this helicopter design creates so much vibration the helicopter will never be usable for any flight longer than a few minutes. It just shakes itself apart. The vibration is 10 times the amount of vibration I get with my other gas helicopter that has an Align T-rex 700N clutch in it. A clutch that is made for RC helicopters unlike the Zenoah clutch that is made for scooters. So.... never mind. This helicopter will never fly again. Total flight time; one minute and 10 seconds. What a waste; at least I didn't crash it! I'm going to re-build it as the T-rex 700X electric the kit came as and use the ESC governor.

Author:  Dawiev [ Tue 05. Feb 2019 19:49:13 ]
Post subject:  Re: Governor engaged RPM too high

First I've heard of the Zenoah clutch causing such vibrations. Post this in the Gasser Helicopter forum on HF.

Author:  George Baker [ Wed 06. Feb 2019 10:04:55 ]
Post subject:  Re: Governor engaged RPM too high

Funny... someone told me they had never had any problems; before I bought an unusable design.

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