PPM Y cable with 1 red wire unpluged has been working good for me on vesc 4. I like the redundancy, I can still get home on one motor if need be.
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Thanks. Yeah, bit of Googling showed that the signal is regulated to some other voltage. Mostly 3.3v. Given the VESC must be tolerant to a range of PPM voltages I’m back to struggling to see how the Y cable could break stuff.
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Back when I was considering using hobby Esc’s with built in BEC, I heard somewhere that it was necessary to clip the red wire from on of the Esc’s in a dual configuration. When I started using Vescs, I just carried that principle over. Better safe than sorry. @Jinra Have you actually tried running dual vescs in a Y ppm setup without clipping one of the 5v wires?
No since i use a standard 3 pin servo cable and attach a single other cable to the PPM wire via solder.
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Correct, normal esc need to pull one possitive lead. So tat receiver oni send signal to esc. I make this mistake before. Fried my esc.
I talked to Benjamin last night and he said you should never ever do the Y. The VESC 4 can tolerate that better than the actual designs, but there is no guarantee that this solution will not fry the hardware. You could be lucky or not.100 working Y-twin setups do not necessarily mean, that Nr. 101 will not have an issue. This has nothing to do with cutting one 5V wire BTW! That is confirmed through BV. The new hardware designs will not tolerate the Y-cable and will very likely fry. So promoting the Y-cable will only cause issues and it is not recommended. There will be a warning about that on the VESC Website. Benjamin designed the thing and he will know it best. I trust him on that 100%. Who else should know it better? If someone is of another opinion, and something goes wrong, you have to blame yourself.
Frank
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But why? Whats the reason that its not tollerated by the Vesc 6? And why is the Vesc 4 more robust on this piece?
Wow so we have been doing it wrong all these years, you would think this would be basic knowledge for setup of a dual.
I get that vesc 6 is a different design and does not like the Y cable.
I will keep running Y on vesc 4 though. 
Listen to @blasto on this guys. I just fried another 4.12 because of this nonsense. Guess its heading back to Canada at some point lol
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Just fried by splitting the PPM signal or splitting and not clipping one of the 5v sources? Thanks
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i didn’t clip the +5 from the second vesc and connected the 5v from both vescs to the receiver.
The receiver is fine, one vesc fried.
Its been so long since i’ve done a split PPM i just totally spaced on that.
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Iv always used “can” i was advised when building not to by several people and go with the “y” connection but made my own mind up…why wouldn’t you want traction control!
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on a dual drive CAN is the best option in my opinion. However, you can’t run 4 4.12s together on a CAN bus without a mod or shit starts acting funny, so i split the ppm to two master vescs and then each one of those was jumped to a secondary via CAN.
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Well that settles it. Gotta cut one of the 5v wires.
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I’ve been running 4 Vesc 4.12’s for 9-12 months with split ppm and one 5v wire clipped With no problem. Sorry but I don’t buy the Luck argument. Although, I must say that I am fortunate to have 4 high quality Vescs by @chaka
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I went with split ppm in the beginning because it was more simple solution than canbus. People have fried their Vescs by just not getting the settings in bldc right. I haven’t felt any need for traction control even when braking and accelerating in turns. Also I have heard of people having problems with traction control and the canbus setup.
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Response Benjamin from VESC-Project forum:
Dead MCU
I got two VESCs where the STM32F4 had died. The reason was that the ADC inputs for an analog throttle have been connected in parallel. When VESCs are connected to the same battery there will be a voltage differential between them under load due do inductance and resistance in the cables. This voltage differential can reach quite high values and the MCU pins are very sensitive to that. Negative one volt is sure to kill the input and short the whole MCU. The PPM input is slightly less sensitive to this than the other pins as it has a low-pass filter, but it still is a bad idea (the VESC4 had a slower PPM filter and was slightly less sensitive). The CAN-bus can handle around ±60V difference, which is why it should be used on a multi-VESC setup. The CAN-bus also provides other advantages such as cruise control with several motors and traction control.
Solution: Always use the CAN bus to connect VESCs in parallel and set up the apps accordingly. Never connect the other inputs in parallel in VESCs that are connected to the same battery.
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Doesn’t take long to learn how to set up properly and ran good with traction control for me since day one! Each to there own though just make sure you know what your doing. If vedder recommends and uses it that’s good enough for me.
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I agree with you 100% on this. You gotta know what your doing when using a Vesc in either configuration.
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How ever much time you put in to something the better it will be…life,family/friends,business or even learning to build a board!