Brushless motor/esc question/problem
 

Hi guys, new to the forum, getting back into r/c after a 15-20 year hiatus.

Bought a Losi 22 the other day, finished assembly and decided ti make a test run...

I have a Novak pro sc esc and a Ballistic 8.5t motor.

At first, all was good, greatly impressed with the power. But after a few seconds, it got all jerky and would not take throttle. I'd have to bump the car with my toe, move it a little and it woulg go OK. Once I stopped, it was dead in the water again.

Any ideas?

My lhs is closed this time of day, and i was hoping to attend my first race after work tomorrow.


ETA: steering servo still works fine even when dead.

I occasionally get a blinking blue and green status led, which is a possible shut down due to a locked rotor ....

It appears your having a motor sensor issue and would recommend a call to Novak. They have excellent CS

^ Doesn't hurt, perhaps start with the basics. Make sure the connections are good, both the sensor wire and the main power wires. Double check that all the little sensor wires are firmly seated, no dirt in connector, etc. And make sure the large main wires have good connections, correct soldering, etc.

It almost acts like it's "missing" under light throttle (when it's actually moving), but when I goose it, she really comes to life.

Runs fine under moderate to heavy throttle, but stutters under light throttle and usually won't start on it's own from a stop.

I'll resolder all my joints and try again

First things first are your radio batteries fresh? After that check the Reciever connection to the esc check all connections if all of this fails resolder your connections and if that doesn't work it may be a sensor motor esc or possibly radio hope this helps

Well the solution is fairly simple then, punch it! :lol:

Not sure about Novak's current ESCs, some brands can work different than they at least used to. Meaning some setups only use the sensor to get going then don't need it, so I still suspect some type of sensor issue, including the sensor board in the motor. Even dirt can be an issue, is this a new motor?

Hope you get it figured out quick, and hey, welcome back! Once you get the hang of the new stuff you will be amazed.

Well, I resoldered and reconnected everything I could get my fingers on.

Retopped the battery off just in case that might have been an issue.

Everything is brand new as of Monday.

I'll be hitting the shop tomorrow and see what he has to say. Maybe he'll have another set I can try. I doubt I'll have time to get it installed for tomorrow night though. :(

I can think of two things that can cause this (I've had both happen).

1) Try a new sensor wire. If you are getting a locked rotor error, the sensor wire may be bad/not connected securely which does not let the ESC see the hall sensors in the motor. On a related note, the rubber grommet/seal on the Ballistic motors where the sensor wire plugs in has caused me to not get the cable in all the way. I ripped it out of my new one and have had zero issues.

2) There could be 1 or more bad FETs in the ESC. I had one that would sit still unless you bumped it then it would go. Bad transistors.

Turns out it was a bad esc. Luckily, I purchased everything from my lhs and they swapped it out for me.

Got my first race under my belt tonight. Finished in last place, as expected, but had a blast.

There it is right there. It's what this hobby is all about.

^ Bingo :nod: