multigov setup right?

[fluffhead]

Just finished my 600 N build. I had the multigov off in hover mode, 1900 full governer in idle up 1, and 2100 limiter in idle up 2. for hover mode I have the throttle and pitch curves exactly as recommended in the trex manual. for idle up modes Ihave the throttle curves exactlty as described in the multigov manual
I was breaking in the engine by hovering 30 seconds at a time in hover mode. When I finally decided to switch to idle up 1, I was very surprised that the throttle seemed to cut in half! I was expecting it to go up. If the multigov is right, then I was overspeeding when i was supposed to be breaking in my engine :shock:. at least it was running rich (I think).
Does this sound right? does the align throttle pitch curve in hover mode cause overspeeding in hover mode, or is my multigov setup whacked?

[george0079]

You really can't use someone elses setup (Even the ones recommended by the manufacturer) Every radio/servo/linkage setup is going to be different. My 1700 at 32% throttle might give you a 1500 on the head.... Or vice versa....

Best advice is to set the Multigov to full gov in normal, and set it to 1700.... And then get it tach'd

[TheBum]

If you were using a 0-100 linear throttle curve, you probably were overspeeding. I noticed the same thing when I first turned on my Multigov.

[helibalou]

If you were using a 0-100 linear throttle curve, you probably were overspeeding. I noticed the same thing when I first turned on my Multigov.

TheBum - How or what did you do to prevent the overspeeding in normal mode with gov off ?
I'm a noob at this and need help setting mine up, I was getting the same behaviour
with my setup.

Thanks,
John

[invertmast]

TheBum - How or what did you do to prevent the overspeeding in normal mode with gov off ?
I'm a noob at this and need help setting mine up, I was getting the same behaviour
with my setup.

Thanks,
John

lower your middle throttle curve point about 10 points

[TheBum]

lower your middle throttle curve point about 10 points
Yep, mine was at about 40%. Great minds think alike.

[helibalou]

Thanks guys, I'll change it tonight.

[jpolidore]

Wouldn't overspeed set at 1700 make it so you would not have to tach it? I am asking because I am not sure. In my theory "in my head" which is the first problem, overspeed would allow you to run the linear throttle curve and still keep the motor from overspeeding.

[TheBum]

Wouldn't overspeed set at 1700 make it so you would not have to tach it? I am asking because I am not sure. In my theory "in my head" which is the first problem, overspeed would allow you to run the linear throttle curve and still keep the motor from overspeeding.

But if your throttle curve was already too high, wouldn't overspeed mode negate the effects of the throttle curve at the higher throttle levels? Wouldn't it be analogous to clipping an audio waveform? It seems to me that adjusting the throttle curve is still important in overspeed mode, unless I'm misunderstanding the operation of overspeed mode.

[jpolidore]

That is exactly why I am asking, the way I see it is (convoluted) but anyway. If you have overspeed set at 1700 and linear curve 0 to 100%, if 1700 rpm is 60% your throttle would stop at 60%? so why do you need the curve? Help me learn....

[invertmast]

in overspeed, it allows you to run a linear curve. Once it hits the predetermined headspeed it ignores the curve and holds the headspeed constant. But when you give it a punch of more collective, the headspeed drops b/c of the increase in blade pitch and induced drag. The limiter then allows for the servo to follow the predetermined throttle curve once again.

[mporlier]

Wouldn't overspeed set at 1700 make it so you would not have to tach it? I am asking because I am not sure. In my theory "in my head" which is the first problem, overspeed would allow you to run the linear throttle curve and still keep the motor from overspeeding.


That is exactly what I tested this week-end as per recommendations in a different thread. So I now have Normal mode 1750 over-speed and I just love it!!!

[helibalou]

That is exactly what I tested this week-end as per recommendations in a different thread. So I now have Normal mode 1750 over-speed and I just love it!!!

Are you guys using a 3 way switch on your flight modes ?
If so what do you have them set at on the multigov ?

Setting Normal to overspeed sounds good.

Why bother using Full Gov, sounds like Overspeed mode and a linear throttle curve seems like the best way to go.

What are some of the throttle curves you guys are using ?

[JAGNZ]

First of all, even with a Gov, LEARN how to set curves, trust me, it's important for many reasons, not the least of which is break-in. DO NOT use a Gov during break-in, it will mask tuning issues. Get a Tach. There is no way to judge headspeed accurately without one unless you have a good ear and a lot of experience. I now estimate very closely to what I tach at. I use the MultiGov in Full Gov Mode in all Flight Modes:

N = 1700
Idle Up = 2050

I use the KISS method and only need one Idle Up. I either am hovering or full on 3D - rarely in between for me...even sport flying works fine in IU for me.

HTH

[mporlier]

I few 3 gallons before installing my multigov. I to only uses 1 idle. I use the second one for tests only. I change only one parameter from the Idle 1 and test it to see the results. I would change either head-speed, expo, etc...

[wingswest328]

Is the limiter mode better for 3D. I had a RL10 and got to the point where it just hunted and 3D was getting difficult. I just installed my multigov and used govenor mode on my IU 1 and IU 2. Would it be better to do limiter? Do I just make my curve linear at 100%

Thanks,
Cameron

[nexus]

TheBum - How or what did you do to prevent the overspeeding in normal mode with gov off ?
I'm a noob at this and need help setting mine up, I was getting the same behaviour
with my setup.

Thanks,
John


Since gov is off in normal mode how can overspeed occur?

I'm new to this too and I'm going to break in my engine over the weekend with my multigov installed. I was thinking of disabling the gov in normal mode (despite I've preset idle1 and idle 2 HS)and run a linear throttle curve 0-50-100 to do the break in, is this possible? Will it mask anything during tuning?

[TheBum]

Since gov is off in normal mode how can overspeed occur?
You can get too much throttle since there's nothing regulating it. Full throttle is too much in most cases.

[mporlier]

Since gov is off in normal mode how can overspeed occur?

I'm new to this too and I'm going to break in my engine over the weekend with my multigov installed. I was thinking of disabling the gov in normal mode (despite I've preset idle1 and idle 2 HS)and run a linear throttle curve 0-50-100 to do the break in, is this possible? Will it mask anything during tuning?

I programmed my curves like everyone else and flew 3 gallons. Then I installed the governor and to my surprise, when I switched from Normal to Idle 1 (1800 rpm) my head speed came down!

So it is easy to over speed in normal. This is why now I have the gouv in over-speed mode 1750 RPM on my Normal mode.

[TheBum]

I programmed my curves like everyone else and flew 3 gallons. Then I installed the governor and to my surprise, when I switched from Normal to Idle 1 (1800 rpm) my head speed came down!

So it is easy to over speed in normal. This is why now I have the gouv in over-speed mode 1750 RPM on my Normal mode.
Yep, same here. I ended up having to drop the Normal throttle curve a lot to get the ungoverned head speed even close to 1800 governed/overspeed. In fact, I think I need to drop it even more because my heli reaches full over-speed RPM (at least from the sound) well before lift-off.

[mporlier]

Yep, same here. I ended up having to drop the Normal throttle curve a lot to get the ungoverned head speed even close to 1800 governed/overspeed. In fact, I think I need to drop it even more because my heli reaches full over-speed RPM (at least from the sound) well before lift-off.

I reach Over-speed before I take off to. 1750 RPM at roughly 60%

[nexus]

I programmed my curves like everyone else and flew 3 gallons. Then I installed the governor and to my surprise, when I switched from Normal to Idle 1 (1800 rpm) my head speed came down!

So it is easy to over speed in normal. This is why now I have the gouv in over-speed mode 1750 RPM on my Normal mode.

So during the break in process, can i say I'm fine with the gov off (less than 500rpm) in normal mode? And should i tach and find the headspeed way too high during break in, I'll just play around with the throttle curve?

After the break in, I'll run full gov in all modes..

[mporlier]

So during the break in process, can i say I'm fine with the gov off (less than 500rpm) in normal mode? And should i tach and find the headspeed way too high during break in, I'll just play around with the throttle curve?

After the break in, I'll run full gov in all modes..

I am positive my breaking in was way to fast now. I would try a max throttle of 60% gov off.

[TheBum]

I am positive my breaking in was way to fast now. I would try a max throttle of 60% gov off.
+1. Your center stick throttle should be no higher than 40%.

[fluffhead]

So during the break in process, can i say I'm fine with the gov off (less than 500rpm) in normal mode? And should i tach and find the headspeed way too high during break in, I'll just play around with the throttle curve?

After the break in, I'll run full gov in all modes..

I think limiter is a better option for hover mode than full governor, because it alows a smooth throttle curve until you reach set maximum rpm and the holds it there.

Full governor mode follows your throttle curve only until 30 percent throttle and then suddenly will kick in to increase your rpm to set rpm., It wont feel as smooth. It wont be smooth going down either, as the throttle will suddenly cut when the throttle curve gets down to 30 percent or less.