HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Sep 06, 2014, 12:22 AM
Drydock Captian
Massey's Avatar
Spanaway, WA
Joined Jul 2006
1,572 Posts
Discussion
Radio burns up ESC

I don't know how else to say this but I think my radio burned up my ESC. The ESC is a LRP Quantum Reversible, and I have used this many times before with other radios with no issue. I had it hooked up to my 7CAP Channel 6 which is attached to the analog dial. I am planning on using that channel for the bow thruster and it is tied in via a mix program to the rudder. Almost as soon as I plugged it in and before I could program it the ESC got hot, but it worked. I redid the program for this radio and it didn't work as well. The battery I was using is a 6V SLA of questionable health so I plugged it into a known good 7.2V NiMH and attempted a reprogram again. Next thing I know all that smoke that was stuffed inside the chips was flowing freely out of the ESC.

The motor was a speed 400 attached to the Bow thruster of my Tito Neri.

Any Ideas if the signal from this channel would cause this? I don't want to fry another ESC, I am fresh out of reversible ones as it is and I am getting 3 new ones here really soon, and I don't want to fry these.

Massey
Massey is offline Find More Posts by Massey
Reply With Quote
Sign up now
to remove ads between posts
Old Sep 06, 2014, 01:49 AM
Sea Dragon-Lover
Umi_Ryuzuki's Avatar
PDX, OR
Joined Dec 2002
10,277 Posts
I have had similar things happen to ESC.
It is like the motor grounds out through the Reciever, and poof the
receiver wires are smoking. You have to be fast to save it.

Not sure what happens... But I put new wires to one of my Robbe Rookie, and
it came back and is working fine.
Umi_Ryuzuki is online now Find More Posts by Umi_Ryuzuki
Reply With Quote
Old Sep 06, 2014, 01:57 AM
Drydock Captian
Massey's Avatar
Spanaway, WA
Joined Jul 2006
1,572 Posts
I wish this was the receiver wires, this was the transistors... Melted the housing of one and it happened so fast I could only unplug it and watch the smoke leave the case.

Massey
Massey is offline Find More Posts by Massey
Reply With Quote
Old Sep 06, 2014, 06:44 AM
Registered User
Blackpool, Lancs
Joined Feb 2006
2,929 Posts
In a multi ESC layout, a bad main ground line connection will cause motor current to flow via the RX and the signal lead, which turns into a fuse/smoke generator.
I have also killed ESCs by giving the control side 6 volts when it was only designed for 5 max, or its own BEC. Managing to connect power reversed did the same job. No experience with the OPs items, just general principles.
mfr02 is online now Find More Posts by mfr02
Reply With Quote
Old Sep 06, 2014, 12:20 PM
Drydock Captian
Massey's Avatar
Spanaway, WA
Joined Jul 2006
1,572 Posts
At the time this was the only thing connected to the RX, and the ESC was also the power supply for the RX. The RX seems to be ok I plugged a battery pack into it and powered a couple of servos after. This ESC used to be in a monster truck I had and it powered a 540 sized motor and ran off a 7.2 v battery. I know that I was good with the power source and the motor was not over doing the unit either.

I had it wired like so

Red battery +
Black battery-
Blue motor -
Yellow motor +

The only thing that I can think of and I'm not even positive this is an issue is there is no null signal on this channel when it is in center position. If so could that have caused the transistors to start rapidly switching and overheat but not power the motor? If the radio does not put out a null signal and the null point is a product of the ESCs programing then I would have thought it would have gotten better and not worse when I reprogrammed it. With my computer radios for my cars I have a null point adjustment, I don't on this radio.

Massey
Massey is offline Find More Posts by Massey
Reply With Quote
Old Sep 06, 2014, 12:40 PM
Registered User
CaptCB's Avatar
United States, CA, Orange County
Joined Aug 2011
2,084 Posts
Like was posted above, IF, your wiring was not absolutely solid, it could have tried to make a better "motor" or, "battery" connection, by using the speed control circuits. Say you need 3 amps, wire it like you need 15, and you will never have a problem. Unless of course, the component, "just" fails.
CaptCB is offline Find More Posts by CaptCB
Reply With Quote
Old Sep 06, 2014, 03:12 PM
太刀風
Tachikaze's Avatar
United States, OR, Eugene
Joined Jan 2003
1,071 Posts
I think you need to step back and look at the wiring from your power source to your receiver ( ESC) and assure that there is not short there.
Then look at your wiring from the motor to the ESC and assure there is no short there.
Check for the most obvious first.
Then, connect the ESC to the receiver with a battery pack for the receiver with no power going to the ESC other than that from the receiver.
Then connect a servo to said receiver. If this works then you can be assured that the receiver/transmitter/ESC set up will work.
Then remover the battery pack from the receiver and run power to the ESC via a known good battery with no motors connected to the ESC. If not magic smoke, place volt meter on leads from ESC to motor, check to assure there is a readable power output. You have now confirmed that the ESC/Battery/Receiver combination works.
Then connect ESC to motor via alligator clips ( so you can quick disengage if needed) and see what happens.
From what you are describing, I am suspecting mfr02's explaination is high on the list.
Tachikaze is offline Find More Posts by Tachikaze
Reply With Quote
Old Sep 07, 2014, 05:40 AM
Registered User
Blackpool, Lancs
Joined Feb 2006
2,929 Posts
I pretty much discounted the wiring from the OPs description, being of the magic smoke coming out of the ESC itself.
My favoured method of destroying an ESC has been to apply voltage incorrectly, either too much or the wrong polarity. I have had one transistor of the output bridge stick on, which effectively puts a dead short on the power when the other half is used, but that should only be a problem on one ESC in a bunch, it should not repeat. I have heard stories of plug-in devices from the pre-2.4GHz era not working properly with some RXs because the new equipment's frame rate can be much higher, confusing the pulse width detection with the shorter "off" phase. I have no idea whether this could cause the output transistors to switch out of sequence and create an internal short.
For testing, I would be inclined to use a supply not capable of high current, say, having a 1A fuse in the supply. Unloaded, the ESC should draw next to nothing, with a light load to act as an indicator, it should be possible to prove that the setup can work without destroying more electronics if the ESC decides to internally short itself out when presented with the signal from the RX.
mfr02 is online now Find More Posts by mfr02
Reply With Quote
Old Sep 08, 2014, 10:02 AM
Drydock Captian
Massey's Avatar
Spanaway, WA
Joined Jul 2006
1,572 Posts
Thanks for the info mfr02, I have installed 2 more ESCs to this radio powered by the receiver only and they seemed to program ok and also seemed to work fine too. The fried ESC seemed to work like this too, then I powered it with the external battery. I will try installing a fuse in the power circuit to see if I can power it up externally and get it to work without frying another one.

Your explanation of the pulse width keeping a transistor turned on is kinda what I was suspecting may be happening. This is an aircraft receiver, and as I don't know a lot about them I can only imagine that they have a higher fidelity due to the nature of the craft it is designed for and therefore may not be 100% compatible with low end car ESCs. I will just have to test more... This is a time where I wish I had access to an O-scope.

Massey
Massey is offline Find More Posts by Massey
Reply With Quote
Old Sep 08, 2014, 01:42 PM
AndyKunz's Avatar
Illinois
Joined Sep 2001
23,455 Posts
The interface is the same, surface or air. The rx makes no difference there (although modern receivers put out 3V pulses and old ones put out 5V or V+, but that's the same air or surface).

Andy
AndyKunz is offline Find More Posts by AndyKunz
Site Sponsor
Reply With Quote
Old Sep 08, 2014, 02:01 PM
Registered User
CaptCB's Avatar
United States, CA, Orange County
Joined Aug 2011
2,084 Posts
Almost ALL, car speed controls "are BEC", and, if you turn it on with the BEC switch, AND, have another power source going to the RX, you WILL fry, the speed control!!!
CaptCB is offline Find More Posts by CaptCB
Reply With Quote
Old Sep 09, 2014, 02:20 AM
Drydock Captian
Massey's Avatar
Spanaway, WA
Joined Jul 2006
1,572 Posts
Thanks CaptCB, I do know that one! Not gonna say how I know about that but I do and that was not the case this time. This ESC just wanted to fry!

Ok so I got my order from England today and did a step by step test. First up was a receiver battery pack attacked to the RX and the ESC as well. It powered up and accepted a program. Next was receiver pack unplugged and the ESC powered up with a 6v SLA, no motor. Again no issues, I also for giggles reprogrammed it again. Next I plugged in a spare 380 sized motor, and good to go the motor worked both in fwd and rev. Lastly I plugged it into the bow thruster and all is well. I guess the other ESC just was not happy being an ESC.

Massey
Massey is offline Find More Posts by Massey
Reply With Quote
Old Sep 09, 2014, 07:18 AM
Registered User
CaptCB's Avatar
United States, CA, Orange County
Joined Aug 2011
2,084 Posts
There is a reason, that a lot of us are using the "MTronics" speed controls. Also, at a heavier amp rating than is really needed, and, have a spare. I don't understand the guys that want the "$9.95 Special" from HK, and then "wonder," why their boats do not run right.
CaptCB is offline Find More Posts by CaptCB
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion i have now burned up two ESC's!! Darn it! orthobird Electric Heli Talk 17 May 19, 2014 03:55 AM
Discussion Burning up esc's after crash fotosaccion Multirotor Power Systems 5 Feb 21, 2014 02:54 PM
Help! Multiplex Tiny S - Micro Servos burning them up uibkRbCs Radios 5 Feb 18, 2014 02:02 PM
Discussion Can a high torque servo burn up an esc? Cwupilot Electric Plane Talk 7 Dec 16, 2013 08:27 AM
Question Did i burn up my motor? TEAJR66 Electric Heli Talk 5 Nov 09, 2013 11:12 AM