PDA

View Full Version : Motor timing and Torque



Gary
07-29-2011, 10:03 PM
There has been a lot of post's on timing for motors but one thing that has not been mentioned is the efect on motor torque from timing. Will a lower timing number increase torque on high rpm's or does higher numbers automatically raise torque and power? Or is there no efect on torque ......just rpm increase? Any thoughts on this? :olleyes:

Boaterguy
07-30-2011, 12:49 AM
Interesting question, isn't the timing how far ahead of the magnet the coil will activate? if so, the in would be like pulling your arm on a bar, the farther you reached the less power you have. This is all a guess, the answer will be interesting.

Lockk
07-30-2011, 09:32 AM
Simple answer is timing wont have much effect, but if you fail to put timing in or its far enough out to create significant heat then torque will be affected. Heat is not Mr. magnets friend!

Torque is linear with current and RPM is linear with voltage (in general) when speaking about a BLDC motor so torque is significantly more affected by current then timing, our ESC's have timing because they are sensor-less (Tekin actually makes ESC & motors that are sensored) and for the way most of us drive (I know one speed WOTH :w00t: ) fixed timing works.

Fluid
07-30-2011, 09:43 AM
Actually many/most ESC do not use "fixed" timing but instead have variable timing in their programing. Sensored BL motors are old skool, Aveox sold only sensored motors for years before Hacker and Lehner motors became popular in the US during the late 1990s. The only reason that car motor companies like Tekin et al sell sensored setups is because these have more precise part-throttle/brake control for scooting around a tight race course in traffic.

Timing has more to do with motor efficiency and if set wrong for the motor characteristics and amp loading the motor/ESC will overheat. You can gain some power with some motors by advancing the timing but gong too far can cause damage. Too little timing for the motor/current can mean overheating too. You won't see much difference in torque by playing with timing.


.

HTVboats
07-30-2011, 10:21 AM
My understanding is a "Y" wind motor is a higher rpm and timmed different than a "D" wind motor, which has more torque and uses little timming. How do you find out what each motor needs for timming? Is it something the manufacturers have charted somewhere? My Swordfish has 3 settings low-med-high with what looks to be some overlap. My Castle ESC can be programmed to any timming in one degree increments. Or just use auto settings?

BILL OXIDEAN
07-30-2011, 10:22 AM
Modern advancements have changed things a bit.
Our newer motors sensored or not have physical timing advance on the motor itself meaning you can adjust the timing on the motor itself as well as the speedo.

Our new speedos have an astounding amount of timing advance 65deg to be exact.
Advancing the timing on the speedo has little affect on torque characteristics, but the physical timing on the motor has just about everything to do with torque vs rpm. Crank the endbell up and rpm increases.

Torque increases right along with it to a point then rpm continues to ramp up, while torque goes downhill. Every motor has a powerband and it can be optimized with the prop.

Timing advance is a double edge sword. It can seem like free speed to a degree but pass its threshold and you're throwin' a barbeacue.

The key is to optimize the powerband through timing advance and that can only be done by checking temps and monitioring performance as you go up.

To answer your question, YES timing DEFINITELY affects torque as the rpms increase.

dana
07-30-2011, 10:51 AM
[QUOTE=HTVboats;343444]My understanding is a "Y" wind motor is a higher rpm and timmed different than a "D" wind motor, which has more torque and uses little timming. How do you find out what each motor needs for timming?




i disagree with this. i have 2 leopard motors, both are "y" wind but one is 2200kv the other 1700kv. im still trying to figure out timing as well.... is timing based on the wind or the kv? anyone? i have them set to 15

BILL OXIDEAN
07-30-2011, 11:10 AM
For what you guys are doing, some depends on how many poles the motor is.

m4a1usr
07-30-2011, 11:30 AM
The answer is pretty simple to the question of which type motor has more torque. A "Y" type winding has more torque at a given RPM then a "D" winding. Thats because each winding is exposed to a larger magnetic field. To measure a motors torque, one of the calculations is magnetic flux lines per centimeter squared, per magnet pole. Since a "Y" motors construction is 2 series of windings per phase, the rotor is exposed to a larger field density. For more information on motors and their behavior read this. http://www.reliance.com/mtr/mtrthrmn.htm

John

lectriglide
07-30-2011, 01:00 PM
My understanding is a "Y" wind motor is a higher rpm and timmed different than a "D" wind motor, which has more torque and uses little timming. How do you find out what each motor needs for timming? Is it something the manufacturers have charted somewhere? My Swordfish has 3 settings low-med-high with what looks to be some overlap. My Castle ESC can be programmed to any timming in one degree increments. Or just use auto settings?

The general rule seems to be "D" winds use lower timing (0-10 degrees) while "Y" winds like (10-15 degrees). I have a doc with a bunch if "snippets" from various threads about timing somewhere on my work computer. If anyone's interested, I'll find it.

tunnelvision
07-30-2011, 01:10 PM
The general rule seems to be "D" winds use lower timing (0-10 degrees) while "Y" winds like (10-15 degrees). I have a doc with a bunch if "snippets" from various threads about timing somewhere on my work computer. If anyone's interested, I'll find it.

I would definitely like to see that when you get a chance. Thanks!

Rumdog
07-30-2011, 01:11 PM
Seems true. However D winds while some call them amp hog (which isnt actually true) Have for me had more balls than any othe motor. Specifically the 1527 1.5d. The motor is a torquey beast at any rpm at 5 or 6s for timing, d winds run more efficiently at 0-10 degrees. Y winds run great at 15 from my experience and from tips from other experienced boaters.

JIM MARCUM
07-30-2011, 06:00 PM
56668Here are the timing tables for SeaKing ESCs. Should work for any brushless motor ESC combo.

Mel279
07-30-2011, 09:53 PM
hi guys

I would like to know if my 4082 1600kv motor is a Y or D winding? Im not familiar with those terminology.

Fluid
07-30-2011, 10:02 PM
http://www.leopardhobby.com/product/product_veiws.asp?id=1417&functionID=01020201

That motor is a 2Y wind.


.

Mel279
07-30-2011, 10:05 PM
http://www.leopardhobby.com/product/product_veiws.asp?id=1417&functionID=01020201

That motor is a 2Y wind.


.

thanks Fluid, appreciated:thumbup1:

lectriglide
07-30-2011, 10:19 PM
56668Here are the timing tables for SeaKing ESCs. Should work for any brushless motor ESC combo.

That is merely the different timing settings available with that esc. It does not suggest any motor esc combinations and their most efficient settings.

JIM MARCUM
07-31-2011, 04:09 PM
True. But it gives a starting point based on how many LIPOs you are running. You still have to test your boat setup to find what works best for you. JIM

Rumdog
07-31-2011, 04:28 PM
That isnt how the chart works, Jim. It is only swhowing the options in order for use when programming through a TX. Voltage is in no way affiliated with the motors optimal timing.

JIM MARCUM
07-31-2011, 05:00 PM
Damn!!! So much to learn - So little time. But, it's good to finally know what the Leopard motor charts means. For example the 5692 motors come in 3Y, 4Y, 3D and 4D models. The higher KV motors (1340/1000) are D, & lower KV motors (730/540) are Y. So, what does the 3 or 4 mean in 3Y 4D? All are 4 pole motors. There must be some correlation between KV & Y/D motors. JIM

siberianhusky
07-31-2011, 07:01 PM
I assumed that the 3 or 4 is the number of turns or winds, thats the way it worked in brushed motors, I could be totally wrong in assuming it works the same in brushless, but I think it does.
http://formuladrc.forumotion.com/t114-explanation-of-delta-and-wye-wound-brushless-motors

JIM MARCUM
07-31-2011, 07:19 PM
Well, all of the Leopard 5692 motors are 4 pole motors. You may be right about 3 or 4 meaning turns. Somebody on this forum should know. Yes, with all of my "old" brushed motors the number ment the number of turns of wire wrapped around the armature. JIM

RandomHero
08-25-2012, 11:50 PM
what about a leo 4082 2200kv 1.5y?

MassiveOverkill
08-26-2012, 09:02 AM
I've had to rewind my stock motor since you can't get a replacement without going directly to China. I learned alot from this forum and website:

http://www.rcgroups.com/electric-motor-design-and-construction-361/

http://www.bavaria-direct.co.za/models/motor_info.htm

Here's my rewind:

http://img.photobucket.com/albums/v632/MassiveOverkill/SuperMonoX/66d4564f.jpg

Not something you should have to do on the higher $$$ motors, but a great way to take a 12$ motor and add some more reliability\power\efficiency.

I can't imagine only 4 winds around a coil......the wire would have to be ludicrously-thick. I would be more apt to believe the 3-4 refers to the number of stators, but I'm still a noob to brushless.

I've experimented with rewinding this motor a bunch of times, and in two experiments I used the same number of strands\winds\turns and did one with a D termination and one with a Y. The D termination probably exceeded my original 3300KV rating and the boat ran with barely any of the hull in the water. I would say the boat was easily going 35-40mph (stock is 30mph) and the motor quickly burned up on its first run.

The Y termination didn't have as much top end as stock but was very hard to control in turning in a smaller area as the torque was amazing.

I simply wanted to get back my stock KV rating, so I had to go with less strands and larger wire with slightly more turns...........more turns equals more torque and less heat while less turns equals more KV but less torque.

A D termination has 1.7 times the KV of a Y termination per turn while the Y termination has 1.7 times the torque of a D termination per turn. Obviously the D termination consumes that much more power and will run hotter than a Y termination.

A D termination can get away with less turns to achieve the same amount of KV of a Y termination.

Notice that I say 'termination' as D vs Y is a termination which is more accurate than calling it a wind-type, unless you're referring to the fact the motor is wound to accommodate that type of termination.