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View Full Version : Why did I fry my forward 3010 fet using Atomic Standard motor?


Chicken Little
2008.03.27, 11:36 PM
It's been bugging me for weeks. I bolted it onto the chassis...put a few drops of motor oil in the front and end of the motor can, and a tiny bit of comm drop. I kept run times at 5 minutes and on the 3rd set of fresh batteries, it just went kaput!

I'm pretty gun shy about Atomic motors now as I have also heard of other issues pertaining other Standard motors. So can anyone shed sum light on what to do in the future to avoid this problem?

bermbuster
2008.03.28, 08:35 AM
It's been bugging me for weeks. I bolted it onto the chassis...put a few drops of motor oil in the front and end of the motor can, and a tiny bit of comm drop. I kept run times at 5 minutes and on the 3rd set of fresh batteries, it just went kaput!

I'm pretty gun shy about Atomic motors now as I have also heard of other issues pertaining other Standard motors. So can anyone shed sum light on what to do in the future to avoid this problem?

Put more powerful FETs in and or stack them....
My son burnt out his forward FETs by getting stuck and revving the motor trying to get unstuck....just a few seconds....Lucky for us my LHS (Majs in Saddlebrook, NJ) he does awesome FET work.

Apie
2008.03.28, 10:05 AM
Do you think I will have a problem blowing 2x2 PN AN0113 fets w/ Atomic standard motor? You are making me nervous!

Chicken Little
2008.03.28, 10:48 AM
That's the thing...I never got stuck and kept revving forward. They were clean easy runs. I had planned to keep my fets stock at 3010. Lucky for me I was fortunate enough to have Willy Wong upgrade my fets. But I have reservations in using Atomic motors from now on.

mk2kompressor
2008.03.28, 11:03 AM
the fet couldve been damaged from a previous run,how long have you had the car?

Spoon
2008.03.28, 11:42 AM
Do you think I will have a problem blowing 2x2 PN AN0113 fets w/ Atomic standard motor? You are making me nervous!

I don't think you would have a problems with any 2x2 stack and standard motor.

Chicken Little
2008.03.30, 06:59 PM
I've had the car for only a month. The previous motor was a Speedy 07 BB. Once I had the Atomic Standard on, it only had 3 sets of 5 minute runs each with fresh batteries.

xxam
2008.03.30, 08:40 PM
I just blew the same forward fet, during my main at the Atomic world race in NYC. (ruined my day.. could not finish)

Upgrading the fets were not an option, as I was running in the stock class. My gearing ratio was not too low, either. I think that Atomic standard motor is not a good match for a stock fet. I just "heard" that Jacob, blew 2 boards while there. (same issue - forward fets and stock board) .. and he was the winner of 2 classes. Chicken...skip this motor.

mferrini
2008.03.31, 06:32 AM
mmm curious.... I sell a PCB that I run ATM stock motor over a long time, the buyer put a ATM standard and blow the fets too. I start thinking there some issue with that motor.

Felix2010
2008.03.31, 04:09 PM
Something to remember about motors is a motor's specifications are only one piece of the puzzle when considering if a particular motor is "FET-friendly", whether you are talking 3010 "stock-FET-friendly" or "2x2 4562-FET-friendly", etc.
There can be several reasons why a supposedly-"safe" motor blows an FET. Motor binding can be a culprit. The brushes may not be properly seated, or be pushing down too hard and could cause commutator high-friction/binding. Normally brush-tension isn't a problem(a certain amount is a good thing, and necessary). But a faulty brush could cause excess friction on the comm; Or the comm may not be true - Both these things can affect how easily the armature spins.
Bearings could be bad, even new ones. Or bearings could be over-greased from the factory and not spin as freely as one would think, causing more Amp-draw than the motor normally would use. When I build/assemble a motor from scratch , I like to "dry" my motor cans' bearings and apply a top-quality bearing lube (Not grease) for optimum bearing RPMs.
Another thing to look for: The armature may be binding against either the endbell or the opposite-end, inside, against the motor can. Loosening the endbell can alleviate armature shaft binding sometimes. Making sure the armature has some fore/aft "play" inside the motor can is something I like to check for. Only a millimeter or two is necessary and can make a big difference.

These are some issues I have encountered in my motor testing and development. I have a decent collection of both factory/machine-made (Atomic/PN) motors and custom hand-wound motors. Fellow member Flashsp-2 has built many Top Secret Motors and these are some of the minute-details that go into making a motor. Before installing a new motor, a simple motor Break-In (There are various ways to do this, but simply running the new motor on 1 or 2 AAA-cells for 10minutes or longer) is a very good idea to help seat the brushes and make a nice,true spot on the comm for the brushes to sit. Also spin the armature by hand to see if it has a lot of friction (More than just the usual brush-friction).
I have also had FETs blow on me after several runs with a particular motor. Sometimes an FET weakens from racing and being overheated/cooled over time, and finally it fails.
Just some things to consider.:)

andreophile
2008.04.24, 04:27 AM
I plan to order an Atomic AWD stock BB motor soon. I have a stock MA-010 PCB with the 3010 FETs. I don't want to risk blowing my FETs even if there's a little chance of such a thing happening with the Atomic AWD stock BB motor. Should I go ahead with the Atomic or just go for a more expensive option of Kyosho AWD X-Speed (shipping is ridiculously more in that case) motor?