RE: Jetti Pro Spin 99
Where did you guys get the setting for timing advance (24deg, etc)? Timing advance uses energy, the higher the number the more energy used and heat produced. I'm not saying 24deg is wrong, just want to know where it came from. I have a Pletty Advance also. I looked in several places (websites, ESC manuals, motor manuals, etc) to find a recommended timing setting and found nothing.
Based on my few hours of research:
*The ESC and motor work as a system to know when to switch current (corresponding to positive/negative and magnet poles), based on position of stator and magnets.
*Timing advance is an ESC setting that allows the user to mess with the system. You are altering when the current changes - timing ADVANCE implying that the current is changing ahead of when the system would do so otherwise. What this does: creates a pulling force on the rotor before it aligns with the stator.
I think it is important to understand how this stuff works before I go messing with it. So, here is a great analogy. A lot of people talk about compression in an IC engine. Forget that. Think about riding a bicycle. For the average guy riding a bike, he pushes down on the pedal. Your body senses when the pedal is at the right position and you push down on the pedal. This would be no timing advance. Now imagine you have those fancy bicycle shoes that clip into the pedals. (I had them once and fell in a big cold puddle. It sucked.) The point of those shoes is so you can PULL on the pedal while the other foot is pushing down. You are now simulating TIMING ADVANCE. On a bicycle, there are basically two key points (sort of corresponding to the top and bottom, or really front and back, of pedal stroke) 180 degrees apart. If you started pulling up exactly at 180 degrees (just as you pass the bottom) you would burn a ton of extra energy, using imagination it seems like it would be pretty difficult. There will be some ideal point where you want to start pulling, for optimum power and efficiency. You could also really screw up and try pulling on the pedal before it gets all the way to the bottom of the stroke. You'd end up trying to pedal backwards and pulling against the foot on the other side. Our motors have 3 poles, so they are 120 degrees apart, and 60deg advance would be half way between poles.
Ok my attention span is shot. Hopefully that expalained something to someone. At least I learned from it. So timing advance - if you feel you are burning up too much energy, reduce your timing advance. The ESC should be able to figure out when to push and pull on the magnets without us telling it otherwise. If people are using 24deg and it's working, then use it. But if there are issues with power and consumption, try lowering it. From what I have read the Pletty has more than enough power, I am sure we can afford to run at a lower advance setting.