EZ Run 80 Meltdown

[vtxnitro]

Hi
Just thought I would share this story cause I have a couple questions. I just convereted my revo 3.3 to brushless using the rc monster mount, techno battery tray and straps, Hobbywing EZ Run 80 A controller, Fiego 9xl motor with heatsink and fan, 2 2cell lipos wire wired in series and a 17t pinion. I ran this setup and it was awsome the truck ran great until I stripped a spur gear Motor temped at like 145 F and the speedo was at like 100 F. Fast forward about 5 days I get the new spur gear and reset the gear mesh maybe just a tad tighter thatn last time but it does not feel tight at all. I put the truck down it goes about 100 feet then starts kinda jerking by the time I get the the truck it looks like someone put a red smoke bomb under the body, then the smoke quits and I can see the controller under the body on fire pretty good it at this time is melting the lexan body so i pull the pins and rip the body off and flick the flaming speedo off the truck and into the grass with a screw driver in and effort to salvage the truck and prevent a major lipo fire. End result truck is not bad, speedo is all but unrecognizable, one lipo pack is not gonna make it ( it never puffed or anything but a corner got melted prety good but not enough to get throught the foil cell packing or cause it to vent infact cells still held voltage fine just not gonna risk it), lexan body totaled. I got off pretty lucky I think, but my question is this. Is this somethig I did or did the chinese controler just self destruct. I did not change anything on the controller setting except to set it to manual voltage cut off at 3.4 volts per cell. Punch was set on 5 and timing at 15 just like stock.

[BrianG]

Sounds like it was pulling too much current and went into thermal runaway. The tighter mesh could have had something to do with it, but would think it would have to be pretty tight to cause that.

Also, did you change any of the settings? IIRC, setting 0 punch and/or 0 timing does cause problems...

[vtxnitro]

No, punch was set at 5 and timing was at 15 like it came from the factory. Maybe your right maybe it was borderline and the extra bit of amp draw from the slightly tighter mesh exceeded the rated amp draw. Should have the problem fixed as I have ordered a mamba max unit to replace. If you have any other ideas let me know I just really want to avaoid having this happen again.

[BrianG]

Well, the MM has about the same rating as the HobbyWing 80 as far as the FETs go, so I would just be careful about mesh tightness. Also might help to dial in some punch control (to help reduce the huge instantaneous currents on takeoff) and add a couple extra low-ESR caps to the power leads.

And since the MM has a linear BEC, you will want to disable it (remove the red wire from the throttle cable) and use an external switching BEC.

[vtxnitro]

OOPs I mistyped I ordered a mamba monster not a mamba max

[pinolelst]

15 degrees timing sounds high for a 2 pole motor...

Steve

[vtxnitro]

Might be I just left it where it was from the factory, figured that would be safe. Guess I was wrong

[emaxxnitro]

Originally Posted by vtxnitro

OOPs I mistyped I ordered a mamba monster not a mamba max

oh then dont worry about it if your mesh is off it will kill the motor or melt the gear and the mamba monster will laugh at it! the mmm is better or = to the hw150

[jsr]

Hopefully you'll have better luck with the MMM, but keep in mind, there are many people with magic smoking MMMs too. The FETs in the 80A and 150A EZRuns are brand name FETs and as good (or better, as one of them, I think the 150A FETs are rated slightly better than the MMMs, but probably not distinguishable difference in actual use). Seems like all the 1/8 ESCs have problems now and then...it sucks from the consumer standpoint, but hopefully as time goes on, 1/8 ESCs improve to the robustness seen in the 1/10 level. They can be made tough enough now (just some changes in design and manufacturing), but the cost of such an ESC would probably make it not worthwhile to people. Good luck and have fun!