Frank Williams and I were out flying this morning and he was doing some flights with a new Ice lite 100 installed.
The first flight was fine just a bit fast (about 5.2, He likes it around 5.5) So the only adjustment was to Adjust
the throttle % down 1/2%. But when the loops were being done it surged, shut down and landed. So we hooked it up but not fly. When he plugged in the power plug the ESC started smoking even after the plug was pulled. So after pulling the battery the smoke stopped. We pulled the ESC and this what U see here. Not quite sure what happened but that was the second Ice lite ESC that malfunctioned for Frank. Any Ideals.   

Frank will have more details when he sees this I just happened to have my phone to get the pictures afterwards.

99 1/2 won't do.

CC recently recalled a number of ICE HV esc's. Anyone know if its the same issue here?

bob branch

Just checked with my nephew about the EF-1 pylon racers. They pull a steady 70A so a lot of them are using ICE75 or 100 - with no issues.  However also note that they would not call on the governor at all and governing generates heat...

Frank, it sounds like an incredible string of bad luck.

How does governing generate heat?  Would it switch the transistors more than merely operating at partial throttle?

Seems too.  I have a plot somewhere of just inside loops on a somewhat breezy day, as the wind carried the bird the thorttle settings went down and the ESC temperature was climbing. 


As for Frank's "bad luck"  I don't believe it either, except so far it is the only explanation that fits the observation! (i.e., we're missing something...)  It is perplexing that that the 50A unit survives while the 100A unit burns up - 3 times so far.

FRANK:
Have you been able to get any of the logged data out of the burnt units? Possibly from a flight before it burnt?  Can you post that AND a log from a ICE50 flight?

Curious what the ESC temperatures are, and what the power spikes look like.

Did you use EXACTLY the same programming in the 100's as the 50's?  (I ASSUMED this)

Did you notice any differences in performance?

Dennis,
The flight performance on the one flight with the 100Lite last week was perfect, just like with the Ice50.  It was about half way into the second flight with the 100Lite that it went BRRRPRPPPRPPPRPPP and quit.  After about an hour we tried to restart it and that when it went up in smoke.  There was nothing on the log, couldn't even get to the log.  The inputs set in the ESC were the same for each.

Now here's something to think about, remember I'm an aero not a EE, ..... but I built a power supply some years back (decades) using an Op amp as the regulator and a big power transistor in the output.  It has a maximum output of something like 30 volts.  When I used the power supply for 20+ volts output, the output transistor ran fairly cool.  However, when set for 5 volt circuits, the output transistor was really pretty hot.  I finially decided that what was happening was that when set for 5 volts the transistor had to drop 25 volts across it, and if set for 25 volts output, the transistor only had to drop 5 volts across itself.  This may not be anything like what's happening in the ESC's (I know they are pulsed), but could it be that the available power that isn't used by the motor has to be dropped by the ESC?  Probably off base here, but I'm grasping for straws.

What you say about the power supply is true.  Especially if it was a linear series regulated supply.  The big difference between the 100 amp unit and the 50 amp unit are the FETs.  In the FET world, the voltage rating makes more of a difference than  the amp rating.  As the voltage rating goes up the layers in the FET gets thicker to prevent voltage punch through. The thicker layers have a higher resistance causing the FET on resistance to be slightly higher.  For a given current you might get slightly more heat in the FET.  On the other hand, the higher amp ratting is achieved by running the basic FET cell (usually hex in shape) in parallel.  For reason to complicated to explain here, FET cell in parallel tend to share the current evenly.  A single FET will have hundreds of cell in parallel.  You can wire several FETs in parallel to get thousands of cells working together for the higher current ratting.

Having said all that I don't think the actual difference of the FETs in the 100 and the 50 is the problem.  The killer of FETs is switching time between full on and full off.  If the 100 and the 50 are identical except for the FETs, the FETs of of the 100 could have more capacitance in the gate drive circut.  This could slow down the rise and fall time of the switch drive.  This could cause the FETs to stay in the partially on condition longer causing some heating.  The speed controller looks at the rotation of the motor and decides when to switch the FETs.  So their could be (conceivably) something weird going on between your motor and the 100 that causes the 100 to miss fire and burn up.  A FET has two failure modes: Overheating meltdown usually caused by overload  and voltage puncture caused by voltage spikes. Over loads are usually caused by prop strikes, bad motors, etc, and speed controller internal timing problems.  Voltage spikes are caused by loose connections, bad capacitors, and who knows what.

Thinking about your problem I don't have a clue what is wrong.  But given the fact that it has happened three time I would guess that you have a weird combination of motor lead length, motor connector, and motor internal resistance that is confusing the feed back loop in the 100 causing it to destroy the FETs.

Any news on this mystery (says the guy who just bought an ICE Lite 100)?