I scrapped my quad a few days ago after the kk2 board died from a few uses. So here I was with 4 DT700 motors. Decided to build a foamie and off we went to fly. Noticed right off the bat that the plane was way under powered. No way was I getting 900G of thrust.

Benched the motor. 9A at full throttle with a Gemfan 11x4.7. Should be around 13A. Went through timing cycles on the ESC. Nada. Grabbed different esc's. Results were kind of crazy. Anywhere from 9-14A depending on the esc. All the motors did the same with some variance. Amperage all over the place on the 5 different esc's I tested.

Some questions... Do some motors just not work well with certain speed controllers even with timings adjusted? Thats 347 grams less thrust. What is causing this issue?

Nightstone

Battery?

Answering my own question... have spent hours researching this and came to the following conclusions.

From what I read there can be alot of variance from esc to esc. Not so much from the electronics but more from shoddy coding for the firmware.

That said... I guess I will be testing all my motors with various esc's as well as just doing amperage tests. I guess there is a reason I was getting more power out of that expensive Turnigy esc vs the cheapo's. But then again the one that was really under powered was a name brand also. Buy one test them and if they pass muster buy more.

I learn something new in this sport every day...

Nightstone

Originally Posted by Nightstone

I scrapped my quad a few days ago after the kk2 board died from a few uses. So here I was with 4 DT700 motors. Decided to build a foamie and off we went to fly. Noticed right off the bat that the plane was way under powered. No way was I getting 900G of thrust.

Benched the motor. 9A at full throttle with a Gemfan 11x4.7. Should be around 13A. Went through timing cycles on the ESC. Nada. Grabbed different esc's. Results were kind of crazy. Anywhere from 9-14A depending on the esc. All the motors did the same with some variance. Amperage all over the place on the 5 different esc's I tested.

Some questions... Do some motors just not work well with certain speed controllers even with timings adjusted? Thats 347 grams less thrust. What is causing this issue?

Nightstone

Timing mostly.

Also occasionally high resistance FETS.

Originally Posted by vintage1

Timing mostly.

Also occasionally high resistance FETS.

Thanks!!! Thought for a while there I was loosing my mind... Got to love cheap equipment.

Nightstone

Originally Posted by Nightstone

Thanks!!! Thought for a while there I was loosing my mind... Got to love cheap equipment.

Nightstone

Do you know which ones drew high current and which ones drew low? Could be super handy info! =D

Here's one other thread on comparing ESC performance.
http://www.rcgroups.com/forums/showthread.php?t=432140

In my own messing around I have found some notable differences in ESC to motor operation up to and including some incompatibilities where they simply would not work together when both the motor and ESC worked fine with other ones.