• If you are new to GiantScaleNews.com, please register, introduce yourself, and make yourself at home.

    We're 1st in Giant Scale RC because we've got the best membership on the internet! Take a look around and don't forget to register to get all of the benefits of GSN membership!

    Welcome!

Help With Motor Timing and Poor Throttle Response (Gecko 120HV)

FlyMike1

70cc twin V2
I can live with it. I never jam the throttle to full like that anyways. I probably wouldnt have notice unless I hadnt seen this thread. I have a few flights on both 125's and I havnt had the motor cutout due to quick throttle advance. But yeah if I quickly advance the throttle it will cut off for a second then start again around half throttle. If I jam it to full it stops at half throttle before I get to full and I have to pull all the way back to get it started again. This is on the ground. But like I said I dont do that kind of throttle moves and I dont see many that do. I'm going to keep them and have fun. 3DNater flew my plane today. I have video I will post later. It does have great throttle advance used normally. If that makes sense.
 

Aeroplayin

70cc twin V2
It makes a lot of sense, and I never jam my throttle either. I do pulse the throttle, but expecting my 20 to 24 inch props to go from zero to 8000 RPMs instantly on the ground without expecting short term or long term consequences is asking a lot, and most guys don't realize the kind of current spikes, voltage sags, and ripple, they create when they do that. If you are using an 80A ESC and typically peak at 72A on the meter, you're asking for trouble with some speed controllers by doing that. I can count on one hand the few ESCs that can handle it. Even blasting out of a hover only means going from 35% throttle to 100% and once the plane is moving, the resistance changes. But still, most guys that experience commutation feel it when blasting through the up line.

Part of the job of the capacitors on the ESC is to smooth out the ripple so you don't fry the rest of the board. When you pop the throttle, you lower the capacitance and raise the inductance. Putting a Castle CapPack on the source side, and shortening the wires on the source side, will lower inductance and raise capacitance. If you seem to have a timing issues only once in a while when jamming the throttle on the up line, for example, this could help.

There are some things we just can't do yet with planes and components. Jamming the throttle on a 3000W system and doing a full speed split-S into crankshaft at the 180 mark are two things I stay away from. Some planes and components may survive the first time, but.... :sadface:
 
Last edited by a moderator:
That is why I am going out to fly it first before condemning it. I mainly fly gassers, and I might not notice this at all. My next biggest electric I currently have is a 60 laser with a torque v2 and 85A Gecko which is insane power and response. I have a A60-6XS that was just on this plane with a 155A gecko and I had no issues there.

Anyways heading to the field for some fun.
 

gyro

GSN Contributor
That is why I am going out to fly it first before condemning it. I mainly fly gassers, and I might not notice this at all. My next biggest electric I currently have is a 60 laser with a torque v2 and 85A Gecko which is insane power and response. I have a A60-6XS that was just on this plane with a 155A gecko and I had no issues there.

Anyways heading to the field for some fun.

Matt, not sure if you already do this, but I setup a curve on my electrics to take out a bit of the linear throttle response and make it fly more like my gassers.
 
I have played with throttle curves on my A60-6XS in the past.

Flew it yesterday and the throttle only bothered me on initial takeoff and wall to hover.

Tried a few props and settled on the 20x12. The sbach is 12 pounds now and like that speed from what I can tell. Will go back and forth on the 21x10. 6900 RPM on the 20x12 and 6550 on the 21x10. Also will try 20x10s.

Anyways the hobbywing arrived. It came with a RPM sensor which is a bonus. The 155A and 150HV are very similar in size, so here are a few photo comparison. Lots more caps on the HW

ImageUploadedByTapatalk1399211564.018879.jpg

ImageUploadedByTapatalk1399211571.755017.jpg
 

Aeroplayin

70cc twin V2
Three questions... Do I see another row of capacitors on the HW under the heat shrink? Is there any difference in the AWG on either the load or source side? Is there a difference in wire length on the source side?

More capacitors also means a better disbursement of heat. More capacitance, overall, means smoother transitions. More capacitance and lower inductance (shorter wires) means less stress on the ESC and a better operating environment under high loads. A thicker gauge wire means less resistance. These are three things I generally look for in an ESC that will go in one of Tom's planes. So far, at least all the muscles are there.

But the proof is in the motherboard, so this can all be lipstick on a pig. The better/smarter ESC is the one that can interpret timing the best. The hardest thing an ESC does is sample reverse EMF during the off cycle of switching to determine motor rotation. It's better to have muscles in the motor, but brains in the ESC.

We can always shorten wires and add a $20 CapPack.
 
Yes, that is another row of caps, the wire gauge is 12 guage on both sides and they appear equal in length, but I have not stuck a ruler on there yet. The Gecko is 10 gauge on the source side like Castles. Plane is in the repair shop so this might not get tested till we get to the Nall. Will report back once I get it all together. I have the fancy HW programmer so I will see what programming I can do with it. I seem to remember more than with the card or the beeps on my 100A Platinum.

I would have gone Castle if they just would get the bloody programming right for 28 pole motors.
 

AKfreak

150cc
A thicker gauge wire means less resistance.
The way I understand resistance it isn't necessarily attributed to gauge, granted all things equal the larger gauge the less resistance. With that said, an 8awg solid core wire vs a multi-strand wire, the milti-strand wire has far less resistance. Electricity transfers on the outside of the wire, the more stands the more outer surface (surface area) the less resistance. This is why a good milti-strand wire is so important. I also see wires that have thick insulation so the strand count is less than wires of the same gauge with a thinner insulation.

The way I understand it, the gauge of the wire determines the current capacity, not necessarily the resistance. But again all things equal, gauge can generally be associated with resistance. Also the larger the gauge the less line loss vs a thinner gauge (of equal strand count)
 
Top