Tribunus 120 headspeeds

[crash-test-tomo]

Hi all, just got the new Tribunus 120a sbec in for my 570 and the setup seems to be ridiculously simple. Im planneto use the scorpion gov, this is my first scorpion esc so not sure if the commanders etc are the same but nowhere Into the setup has it asked me anything about the heli? Lipo volts, gear ratios, desired headspeeds etc...
It says use throttle curves to set your desired headspeeds but how do you actually know what it is? Rpm is shown in the scorpion software but I guess this will be motor rpm? And that il need to actually spool up the heli to get the numbers?
Do I just use a headspeed calculator then with my gear ratio etc to get an idea of the percentages I need for x amount of headspeed?
Cheers in advance
Dan

[Grumpy]

You dont know the actual headspeed but it doesnt matter. What matters is how it flies, so start at a mid range number, say 75%, and if when you fly you find that the headspeed seems a bit low, you just increase the %.. and vice versa.

This is how the governor on almost all ESC's works, only exception I can think of being Castle Set RPM governor, which is a lot more 'fuss'.

[crash-test-tomo]

OK cool, I am fine with not knowing the actual headspeed once its up and flying, problem is that the first flight on this esc will also be the helis maiden. G570 manual states between 2300-2500 rpm, recommending not to exceed 2600.
Im really looking for a way to get a ballpark idea of where I need to be first, how do I know the first time I spool up that 75% isnt 4000rpm?
The esc does autodetect pack voltage and I believe motor poles but there are no boxes for kv and gear ratio at all..
Ive only really owned castle esc's in the past or used fbl govs so that way of doing it just felt 'the norm'

Cheers

[Grumpy]

As long as you have the correct motor Kv and pinion combination as per the Goblin manual then your RPM will be in the right ballpark. The only way you could exceed the safe RPM is if you used too big a pinion and/or too high a Kv motor.

[ragge1]

I bench tested the esc gov with my gearing but got too low HS , but when changed to external PIB then I had where I want it but then I can't use the bailout features from the ESC , ( why I bought it ) to come to the desired HS then I have to go bigger on the pinion
- with esc gov could go passed @2500 HS at 100% trottle
- external PIB = @ 3000 at 100% and my target HS 2700 , so now I'm at external PIB and using vx1e gov

[Grumpy]

I dont know why that would be the case, 100% in the ESC should put the motor 'flat out'. Possibly the ESC needs it's throttle range calibrating?

[ragge1]

did range calibration several time but that didn't help

[Grumpy]

I've just looked at the Tribunus manual and it seems like it might have some sort of 'intelligent' governor calibration process:

If you would like to utilize the internal governor in the Tribunus 200A ESC, select “Recalculated Value” for the first few
flights with internal governor. Select the “Pre-stored value” after your first few flights.

So it seems like the governor might work out it's own maximum headspeed over the first few flight... So possibly the way to go is fly the heli for a few flights during which the ESC will calibrate it's headspeed. Then switch to 'pre-stored' value after the ESC has set itself.

But i'm kinda guessing here, this is different to any ESC I've used.

[crash-test-tomo]

Yes, I been back through the manual this afternoon and it seems you are right.
Iv setup the ecu but had a catastrophic meltdown in the brain, there was magic smoke! I did check the brain manual and it doesnt say not to power the gov port but the slave wire from the Tribunus is rpm and a second bec +/-, so gives 8.3V. I connected the slave to the small sat style plug as normal with brain1. Added power and I have 1 dead msh brain
I give up!

[ragge1]

sorry to hear that , I did measure mine and there was power the was not sure if I should use the opto cable , and it good to have the extra power cable from esc , so I soldered a HW phasesensor to the motor cables and used that for my rpm signal

[crash-test-tomo]

Im.not sure about the opto cable? Had I of used my brain2 it wouldnt have been a problem as the gov port is normal servo style and can take full 8.4V.
Luckily the esc is fine, still beeps the motor and lights up anyway.