Y-harness max length- ATTENTION!

[DISAR]

Today it was one of my most expensive r/c damage day. I had two Y-harness to connect my lipos in parallel which used to work fine but increased the length of only one side in order to use them in my bigger hull as well. I went to measure the speed of my Mean Machine and guess what, blew two ETTIs 150A one with extra caps board one without. The same setup and even hotter used to work fine before the increase in length which was not that much really. My setup is NEU 1512/2D, 4s2p, grim 3855 which also tried upto 442 with no problems. When the blow outs happened the only thing that changed was the one side only of the Y-harness. My harness length was 2" esc side, and 2" each battery side, then changed the one battery side from 2" to 6". And then
I have to clean all this messs now again

[egneg]

Heavy duty bummer - I would be cussing up a storm at the pond and then cry at home.

[andym]

This is the the only good thing about us Aussie's running one pack rule. No probs with a y harness with similar speeds and a good race only last 1 1/2 minutes anyway!

[DISAR]

You know I read so many things about the 1p (ripple current etc...) then I said 2p is safer whic was fine until that. Luckily enough batteries and motor are fine, except that my MM needs a lot of cleaning

[andym]

you just have to love that smell!

[DISAR]

Still on my hands after washing them 3-4 times, and I haven't started cleaning the boat yet!

[bustitup]

sorry I just cant imagine your modified wiring doing that....but who knows

it sucks for sure

[Jesse J]

Man, what a bummer. Been there too and that smell just takes for ever to go away, just lingering to reminding us how fragile FE set ups are. Big loss, feel for ya man. Thanks for the warning, will keep in mind as I am going to more 2P set ups.

[DISAR]

FE setups are fragile and all factors must be taken into account every time we put the boat in the water. The only thing that changed since my last run was the harness, nothing else.

[Capt. Crash]

sorry I just cant imagine your modified wiring doing that....but who knows

it sucks for sure

Hmmmm...I have a hard time with it too....unless the solder joint was cold....but who knows!

That really blows man!

[txboatpilot]

Any picts of the Y harness?? or what is left? This sounds really STRANGE.. I have ran a Y harness with 8" on each side in a VERY high performance 10s2p setup with no issues.. I dont think the blow outs were due to the added wire length.. JMO

What were the temps on the ESC on prevous runs with what props?? What lipos do you run Mah/C rating etc??

[Meniscus]

I'm very sorry for your loss. This information may be of interest now. I used in on my last hull that burnt the ESC: http://forums.offshoreelectrics.com/...ead.php?t=6523

[DISAR]

Any picts of the Y harness?? or what is left? This sounds really STRANGE.. I have ran a Y harness with 8" on each side in a VERY high performance 10s2p setup with no issues.. I dont think the blow outs were due to the added wire length.. JMO

What were the temps on the ESC on prevous runs with what props?? What lipos do you run Mah/C rating etc??

My temps with exactly same setup were 100F +/-10 in all (ESC-motor-bats) and the highest were 130F on the ESC with the 442. I really don't see any other reason. Now that I think it over again it really sounds weird but that's the truth. Another thing is that I sprayed the motor with electrical cleaner but that was 2 days ago. Could this have any affect? I don't think so. Maybe the ETTI's weak point is the long wiring? Again I don't know. The blow out happened about 1 min after starting. The Y-harness is fine, untouched. I will add some photos later but just finished shortening it. My lipos were Zippy Flightmax 4s 5000mah 25C

[AntronX]

It should be well known by now among FE community that long wires will overstress capacitors and blow up your speed controller.

Get rid of that single wire piece in your Y harness going from Y center to the right (in your picture). Run longer pieces of wire directly to your bullets turning your Y harness into V harness.

Go buy another ETTI, but with extra capacitor board and solder it as close to the ESC as possible. Try to make your wires as short as possible, rearrange your setup if that will shave off an inch or two.

[AntronX]

Acetone and brake cleaner work great for cleaning burn mess.