Hello,
I'm using four jDrones AC30-1.0 ESC on my quad and I'm often having problems with some ESC that won't arm when I connect the LiPo battery.
One odd thing I noticed is that most of the time, they will arm without any problem when I'm at home, but on the field, I have a lot of trouble to get the four of them armed and sometimes I'm even not being able to fly! That's very frustrating...
It seems to be linked to the temperature, and I found out that at 20°C, during my tests, only one ESC was having some problem at arming (it took about 20 seconds to arm). Outside, at 10°C and below, only one ESC could arm, and waiting didn't help, the three others couldn't arm at all.
When I'm connecting the ESC connector to the receiver, I can arm any of them manually without any problem.
I used my scope to check the signal sent to the ESC by the APM and it seems to be a correct 400Hz PWM signal (I didn't bring the scope outside, but I guess the APM wouldn't send a faster signal just because of a colder environment?).
I understand that some ESC are not compatible with a 400Hz PWM signal (http://diydrones.com/forum/topics/esc-arming-problem), but I guess that a stock jDrones AC30 should be compatible with such a signal, shouldn't it ?
Did somebody already have such problems with those ESC ?
Could there be another reason for them not being able to arm?
Should I remove the jDrones ESC and buy some others ?
Thanks for your help!
Nicolas.
Replies
I *think* the standard Arducopter ESCs do not have a crystal oscilator for timing, and so can drift quite a bit due to temperature. The drift in timing probably means they are seeing a PWM signal outside the acceptable range for arming. I would recallibrate the ESCs at the outside temp to see if that helps.
D