question on VX-1 nitro gov

[trillian]

I have just setup a VX-1 on a gasser and despite reading everything I could find it seems the governor is not really explained. I have five Spartans now, the previous four are all on electric helis so I have never used the governor in the Spartan.

So, typical things I'd usually expect to see explained are:

1. What sort of mode does the gov operate in? Does it totally ignore the curves and just try to deliver the headpseed you set, or can the headspeed be influenced by the underlying curves?

2. Can I have more than one headspeed? I only see one place to set it in the Datapod

3. can I have the gov off completely in my normal flight mode and have it only active in idle-up?

Maybe I'm just daft (quite likely) but I just don't see answers to the above in any of the literature.

[stargazer]

I set my curves as normal as if you were not going to use a Gov,then try and set the headspeed so its as consistent as possible balancing pitch and throttle curves and obviously getting the engine mixture right.I then turn on the gov,the better you set up the Heli with the gov off defiantly helps the governor work better when its on.I also want the the normal curves just in case the gov ever failed.

You can have a different headspeed in normal,Idle up1 and Idle up 2

Any mode, normal,Idle up1 or 2 can be turned off individual in the advanced Gov menu I believe.

[trillian]

I set my curves as normal as if you were not going to use a Gov,then try and set the headspeed so its as consistent as possible balancing pitch and throttle curves and obviously getting the engine mixture right.I then turn on the gov,the better you set up the Heli with the gov off defiantly helps the governor work better when its on.I also want the the normal curves just in case the gov ever failed.

You can have a different headspeed in normal,Idle up1 and Idle up 2

Any mode, normal,Idle up1 or 2 can be turned off individual in the advanced Gov menu I believe.

Thanks for the info. I have a feeling I'm going to feel silly when I go back into the Datapod because I forgot about the advanced menu items!

For the moment I have normal curves set and the gov off in all modes for the initial flights.

[dw45]

It is straight forward once you go through the data pod, put in head speed for each idle up, hold and normal. works great.

[hedge]

Hey Trillian it's not the advanced menus just the standard ones. As you enter gov menu you get to set gov on or off and headspeed for each mode nor idle 1,2 and hold. Just standard datapod stuff. As far as I know ( and I've been flying vortex gov for a year or so) there is no reliance on curves in gov mode however you should set it roughly right in case you throw a magnet or cut the cable by accident.

[myxiplx]

I know for a fact that the Vortex e-Gov does make use of throttle curves. It uses the throttle curve as it's hint for the required throttle, so this is both your feed forward figure giving you the proactive governor response, and also a way to ensure a smooth governor as the bulk of the throttle input is configured with the curve and the governor is just being used for fine tuning.

[hedge]

I know for a fact that the Vortex e-Gov does make use of throttle curves...

Your so right.... this is about Nitro

[GIXERMAN]

Your so right.... this is about Nitro

that what i thought, i wish people would read the Title of these Nitro threads

back on topic

[myxiplx]

lol, I did notice the topic guys. I was trying to say that I know for certain the eGov uses the curves, so I would expect the nitro gov to work in a similar way.

So ner ner :-p

[trillian]

lol, I did notice the topic guys. I was trying to say that I know for certain the eGov uses the curves, so I would expect the nitro gov to work in a similar way.

So ner ner :-p

I wish the nitro gov would work like the internal gov in the Jives, where it latches onto a fixed % that it sees from the throttle. But I suspect the reason they don't do it that way is because the underlying throttle setting could cause overspeeding of the engine if the gov deactivated for some reason.

[waveydavey]

lol, I did notice the topic guys. I was trying to say that I know for certain the eGov uses the curves, so I would expect the nitro gov to work in a similar way.

So ner ner :-p

I'm confused somewhat, don't most E helis use a straight line in their throttle curves then rely on the governor function to control this. So do Spartan recommend tuning an E throttle curve the same as a nitro one? I can see the sense of a V curve even with governor on a nitro in event of a failure although I don't know how much use it would be to the governor software for look ahead. Difficult to get the engine to react to a constantly changing throttle stick although I can see it helping with cyclic demand as this tends to be more prolonged.

I use a V on VX1's and haven't done anything special with them as far as tuning goes and it works just fine, although I do know people have had problems with revving up and down on their own and some odd hiccups on unloads.

[myxiplx]

Hi trillian, yes, having a known good throttle curve behind your governor is a good best practice, and Angelos is very aware of the importance of failsafes so I've no doubt this is something he considered. I know that the default 'minimum throttle' setting on the Vortex governor is too low in flight in many situations and often needs raising. Angelos has stated in the past that he keeps it at this setting for safety, to avoid over-throttling engines on the bench as many people test a governor by running the system up on the bench with no blades.

In that scenario a higher 'minimum throttle' setting can easily over-rev the engine and damage the model, so he deliberately keeps the default at a safe setting.

And wavey, yes a lot of people use a straight line for their idle up throttle, the Vortex' recommended use of a V curve has caught a lot of people out, it's probably the number one reason why people have governor problems when setting up the e-gov for the first time. An awful lot of people have posted in the Vortex forum on Helifreak with problems because of this.

The Vortex gov will often work pretty well with a flat throttle curve, but a V curve that's already been tuned to the headspeed you want will give you the best behaviour, with the tightest rpm holding, and the least impact on the tail. The revving up and down could well be a sign of the governor hunting, and could be that the target rpm is a little too far away from the throttle configured.

The most common issue on unloads is that the minimum throttle setting is too low, this can need increasing significantly as the default value is really a safe figure rather than anything you'll realistically want in flight.

[hedge]

I recommend setting a rough throttle curve so the engine falls back to a safe level should the gov disengage. Contrary to what's written above the NITRO gov gain is set too high (700size models) most people find they need to lower it some 15-25 points to stop the engine hunting.

[Nick_C]

I had gov problems with my 600n,but Angelos helped me sort it out at AIR this year,i had straight line throttle curves in transmitter and this wasn't working with gov,headspeed was way to low for settings. Angelos put some v curves in transmitter,i test flew and all was perfect,dont think he did anything else to it.

[trillian]

OK here's a question someone may know the answer to: What is the signal that the TX flight mode switch sends that tells the FBL unit to change flight modes? Is there a 'hidden' channel for the flight mode commands?

I've been using a DX7S with my electric helis and it only has one idle-up but I can get a 2nd idle-up by using the mix switch to bump the throttle % (plus I find that I rarely use more than one idle-up with electric anyway).

With the gasser I'd really like an idle-up mode for a bit lower headspeed than whatever the flat-out setting is.

I do also have a DX8 that I have not used because I'd really rather have all my models on the same TX but I suppose if there's no other way of getting an inbetween headspeed I can move the gasser over to the DX8 which has three flight modes.