ESC meltdown!

[ScarabChris]

Brand new ESC's. Both worked perfect right out of the box. Boat never made it to the water, just several perfect bench tests in the boat. Final test before tossing the boat in the water and one ESC melts down. What could cause this? Notice the red and black wire on the RX cable melted together and that chip or whatever melted. So frustrated with this boat. I finally get two ESC's that power the motors in perfect synchronization and this happens.

[RaceMechaniX]

Sure looks like the voltage regulator on the one ESC that burned up and the melted servo leads confirms that theory.
Did you have both red wires plugged into the Y connector or ESC? You would think this should not be a problem if both BEC circuits are delivering the same voltage, however in my experience it rarely works.

In twin set-ups where you use an BEC circuit through the ESC, one ESC's red wire needs to be removed or remove both and use a separate receiver battery.

-Tyler

[ScarabChris]

Ok that was going to be my concern. The RX is the Spektrum MR3000 so it has dual throttle ports so no Y connector is needed. The RX is also powered with it's on RX battery. I did not cut the red wire from the ESC's but thinking back the ESC's I had before I did cut the red wire so only the ground and the signal get plugged into the RX.

Could this be the issue?

[Johnc]

Been there myself,
Need more info (batteries, 6s/4s?, ESC's, motors)
look's like two different ECS's to me. One that melted may not have been what you thought IE: 90amp and not 120amp. Did you disconnect one red wire from the y cable (connecting ecs's to motors and to the rx)? Even if you did, the ECS that melted down could melt those wires (luckily rx didn't melt down as well)
Anyways, I bench tested with 2s (all good). did a couple of runs on pond (all good), put in 6s and didn't get 5ft Silly me: (2 Different ecs's, trying to save $$) come to find out one ESC was only rated up to 4s.
So I learned to keep things symmetrical with "like" components, and not try to mix things up on a twin.

[ScarabChris]

Nope they are the same ESC. The burnt one is just upside down. I am not an amateur on fast electric boats but I do get stumped sometimes. Both are 120 amp. They replaced some older ESC's that were the same except by Turnigy. Again there is no Y cable, the RX has dual throttle ports. Batteries are 3s and motors are Turnigy 2845-3650. I know the setup is correct with regard to battery, ESC and motor compatibility. This is a boat I built over 10 years ago and simply replaced the aging 120 Turnigy ESC's with new Sea King ESC's. One of the old Turnigy ESC's was getting weak.

Only thing I did different and may be the issue is I failed to snip the red wires on the RX wire as the RX has it's own battery.

[Panther6834]

Ok that was going to be my concern. The RX is the Spektrum MR3000 so it has dual throttle ports so no Y connector is needed. The RX is also powered with it's on RX battery. I did not cut the red wire from the ESC's but thinking back the ESC's I had before I did cut the red wire so only the ground and the signal get plugged into the RX.

Could this be the issue?

First problem I see. You say you're have the Rx powered by a separate battery, but it's also receiving power from both ESC's. Why do you even need to power the Rx from a separate power source? The power from just a single ESC's BEC should be enough. Besides, if the BEC from a single ESC isn't providing enough to power the Rx & servo, them the proper configuration would be to separately power the servo (ie. not the Rx) by using an external BEC. I'd say, you're lucky you only fried one ESC...you might have ended up frying them both, and possibly your Rx and/or servo as well.

On a side note, considering the Rx you're using, did you also make certain you're using a compatible Tx. There are only a few transmitters compatible with the Spektrum MR3000...specifically, the DX3S (SPM3140), DX2S (SPM2120), DX3E (SPM3160), and the updated version of the DX2.0 (SPM20220) & DX3.0 (SPM20320). No other surface transmitters are compatible...and, from what I understand, no air transmitters are compatible, period.


~ More peace, love, and kindness would make the world a much better place

[RaceMechaniX]

Only thing I did different and may be the issue is I failed to snip the red wires on the RX wire as the RX has it's own battery.

That is your problem. Just use a small tool to remove the red pin from both ESC plugs. Fold it back over and tape it to the other wires. Run the receiver pack as the only power source to the receiver.
Don't clip the red wires are you may need to insert the red wire back into the plug if you use a programming box.

[ScarabChris]

Ok let me clarify one more time I think people are not reading everything. The boat in question I built over 10 years ago. The Spektrum MR3000 has been in the boat since then and I have been using the Spektrum TX as well. This is not a new setup. This is an old setup that I simply replaced the aging ESC's with new ones.

Yes the RX has it's own battery and it has always been this way. I see now I made the mistake of not removing the red wire from the ECS to the RX. Looking at the old ESC's I took out I see that I did have the red wire removed.

[ScarabChris]

That is your problem. Just use a small tool to remove the red pin from both ESC plugs. Fold it back over and tape it to the other wires. Run the receiver pack as the only power source to the receiver.
Don't clip the red wires are you may need to insert the red wire back into the plug if you use a programming box.

The moment you mentioned that in your first post I was sure that was the issue. I dug the old ESC's out of the parts box and I see that I did have the red wires removed on the old ESC's. It had just been so long ago that I set up this boat I forgot to do that when putting in the new ESC's. Luckily I didn't burn both ESC's. I already ordered a new ESC so when it arrives I willl be sure to remove the red wire on both ESC's.
This boat was a shelf queen for about 9 years then a few months ago I got it going. One of the old ESC's was weak but the boat ran. I then decided to get new ESC's and when everything was installed and tested well I was very happy. Then the final test and it melted down. Could be it happened on the last test because the first few tests weakened it plus I had it turned on for longer. The previous tests were super short. I was so pissed about this last night I was dreaming about it and here is the crazy part. I was dreaming about this and red wires kept showing up in the dreams.

[ScarabChris]

Ok it looks like I got it sorted out....finally!!! Extra thanks to RaceMechaniX for reminding me of what I did wrong. It was because I did not remove the red wire on the ESC's. So it was not just the one ESC that cooked. I also burnt the cool magnetic ON/OFF switch that I can no longer find. It also burnt the RX which I am really upset about. I had the Spektrum MR3000 RX. I love those receivers! They are small and have dual steering and throttle outputs. It burnt up and they are no longer made.

So I had to cannibalize the Spektrum SR300 RX from one of my cars to get the boat going. Then what I did was cut up the burnt MR3000 to make a Y connector or a "buss bar" so I can connect both ESC's to the one throttle input. (I didn't have a Y connector or the parts to make one) This boat runs perfect now!!! Absolute perfect synchronization between the ESC's. In addition to that...the 10 year old Turnigy ESC's must have been super weak. The new HobbyWing ESC's woke the boat up. The old Turnigy ESC's were identical in spec to the new HobbyWing. Both 120amp. This thing is so fast it wants to stand up on the props at full throttle. I know flex shafts will be an ongoing issue especially now. LOL.

If anyone has a working Spektrum MR3000 RX they want to sell let me know!!!

[RaceMechaniX]

Glad to hear you got her running again.