X Vbar Gov Settings

[Twister773]

Just curious what you guys are ending up with for the Vbar governor settings. Also, is anyone using the auto bailout function or idle during bailout?

[aviatorflyer]

I have the auto bailout armed.

[MrMel]

Do use idle at bailout when using bailout, it will protect all (esc/motor/drivetrain)

[Twister773]

I'll give it a go tomorrow

[busterboy]

Yes using idle bailout and its working fine.

[AusAnt]

This is the first time I have set up an external gov, so I have a couple of stupid questions to ask. I have set it up as per MrMel episode 20 and the manual. It seems to work fine, but:

1. I am used to a Jive gov or similar, where the TC setting needs to leave enough headroom for the gov to respond to high load. However in setting up this gov as per the manual and MrMel, I need to have the TC at 85% to get a HS of about 1550. I want to set up curves for say 1650 and 1750 too, but it seems that my TC's will be much higher % than I am used to. I do notice in episode 20 that Fredrik has TC's of 93%, 97.5% and 100%, so does this mean the TC % is just calling up a specific HS based on a % of the max HS specified in VBar gov setup? (I used 2200 as in the manual) If that is the case, does that mean I don't really know what % the throttle setting is at - the gov will just work it out and send it to the motor, and all will be well as long as what I have specified for HS and max HS are within the capabilities of the power train?
2. I know the power system for the XX is all the same, so numbers like max HS have been given in the manual, but just for my understanding - on a new model where I had to work it out, would I put my setup into a HS calc and work out the theoretical max HS at 100% and use that as my max?
3. I did some testing last night with a 14s pack but I just left it at storage charge (about 52V). Will this make any difference to the HS I get? ie. do I need to do setup with a fully charged pack or is it like above where you are specifying a HS as a % of the maximum HS, in which case pack voltage is irrelevant unless it is insufficient to deliver the requested HS?
4. Does everybody have bailout curve set for 40% like in episode 20?

Everything seems to be working well and doing what it should, but I'm just checking because some of this is using different logic to what I have done in the past with ESC govs.

Cheers,
Ant

[Big Fil]

"so does this mean the TC % is just calling up a specific HS based on a % of the max HS specified in VBar gov setup?"

Yes, that's how it works. I'm pretty sure the 2200 in the manual was an error. Most seem to have theirs set to 1800 rpm with % set to obtain the desired RPM.

Here's what happens when you put the Xxtreme specs into MrMel's calculator.

Result for calculation:
Estimated lowest voltage during flight: 48,72
Lowest RPM (due to voltage and efficiency) : 1713

For + performance, keep req. RPM below: 1773
For target performance, keep req. RPM below: 1844
For - performance, keep req. RPM below: 1897

Result is a pointer how low you should keep headspeed so you have enough headroom for the governor to compensate, the higher you go the less headroom and the effect is that it diviate from your target headspeed more (bogging)

[AusAnt]

Thanks Fil,

So I'll change the max to 1800 (I doubt I would want to fly over that anyhow), and will just use whatever TC's I need to achieve the right HS.

So using a storage charge 14s pack for setup shouldn't make any difference then should it?

[Big Fil]

If your just doing electronics setup you'll be fine. However, please please please back the motor off or remove mains and tails if you are using your full flight pack. You don't want your Xxtreme to take a bite out of you!

[AusAnt]

Thanks.

Luckily this frame setup is a lot easier to back the pinion off compared to the Logo 600 setup. I was doing that initially but now I'm testing with no blades installed.

cheers,
Ant

[heli21]

I simply just unplug one motor wire so if it does try to spool up the motor just spins around a bit but it is not a danger.

Rob

[Nko15]

But your ESC wont thank you for that if it ever happens... Unplug at least 2 wires...

[J-Money]

Here is another question do you start in idle up then release the throttle hold just like a kontronics so the esc can read get a TRUE reading of the batts and the motor not to sure about yge / v-bar gov but I thought the yge came from the same programmers?

[rcmarty]

Originally Posted by Nko15

But your ESC wont thank you for that if it ever happens... Unplug at least 2 wires...

True.

Speaking as an electrician by disconnecting 1 lead it will prevent it from starting but your basicly single phasing a 3 phase ac motor. The esc will try to start it but it will try with large amp draws which is bad.

3 phase motors always have phase protection built into the starters to prevent the frying of the motor.

Martin