Another con to split ppm vs canbus with ack is, you lose the ability to change settings/modes on the fly via the android app.
Also I think you get fault codes from the slave over can? Not sure about this.
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Hmm yeah that is quite a big con. Good point.
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I’m gonna elaborate whether you like it or not. 
I have a bunch of boards with ack, and so if some are canbus and some are split ppm (and they are), i have a decent chance of forgetting, and doing something crazy like enabling reverse on just one side.
Also, I usually do detection for both FOC and BLDC mode, and leave BLDC sensorless, so if the sensors take a shit I can flip to BLDC and keep trucking. If I can remember if the board is canbus or split ppm…
And sensors seem to often take a shit.
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Nano-x and GT2b
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Yes, dual PWM (“PPM”) I like mostly because if you do happen to lose your signal due to heavy radio interference, then typically both controllers will cut out at slightly different times which makes it far, far, far less likely you’ll lose your balance and fall off. Instead of one giant unexpected jolt, it’s more like two little jolts about ~75 milliseconds apart, in my empirical experience.
It’s also advantageous in that it’s the only way I know of that completely isolates one ESC from the other, and in case an ESC fails, it’s typically not going to bring down the other one.
It’s not “redundancy” – it’s just “dual systems” like two single motor skates on the same deck paired to the same remote. And yes, you can get home if only one of them is working 
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haha, I thought that might be what you meant after I posted @BillGordon
Actually, the Benchwheel remote has the 6 pins but only one of the power (+5v) pins are active. if you plug in a single reciever to the wrong pin set the reciever won’t power up.
most of the split PPM setups I’ve seen here have the power to the reciever from only one esc, and once I saw someone who just runs the signal cable, no (-5v) and no (-neg)…(forgot who was doing that)
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Ahh, thanks for the TIL.
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This is probably worth discussing. I think if you have 2 vesc with split ppm with neg hooked up, if you disconnect bat- on one vesc, the ppm cable may still complete the circuit? Interestingly this might save your canbus chip from blowing.
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I know @b264 has taken shit for this method but I’m going to come out on record saying that dual receivers saved me multiple times when I was running a nano. it would cut out all the time from radio interference (I commute near the airport and several cell towers) but with dual receivers the jolt was much less. the Benchwheel has no interference so I don’t even think about it anymore
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That’s not necessarily true. Maybe if you have a remote that uses UART on one esc, but that’s not really a factor with split PPM. You just need a separate BT module on each esc. Then it’s just a matter of changing the same settings or modes/configurations on each esc one at a time, but not that hard, and totally doable.
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Or what you do is you keep the canbus up and running but still use the reciever via split ppm when you change setting you make sure to keep the receiver settings inatact
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I’m running dual TB 4.10 VESCs with 3.40 firmware. The CAN cable never worked. Wondering if I accidentally burned out the CAN chip.
Decided to do a split PPM harness after getting some solid advice from @mmaner and it seems to work fine. The downside is that I lost traction control and have to update the settings on both VESCs if I need to make a change.
One thing worth noting is that I couldn’t copy and paste the PPM mapping settings for the pulselength start/end/center and have the motors spin at the same RPM. I manually changed the PPM mapping on both (with different values) to get them to behave identically.
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Could use some help with canbus…I’m building a dual board with two Focbox and plan to connect vie canbus. I’ve used can on several other boards and so far have not had a problem, but I always forget the set up order…@deckos used to have a great video explaining the process, but the link is dead.
I believe both focbox need to be powered up together once the canbus cable is connected, correct?
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Yes, to ensure that your canbus chips don’t die, both escs should be powered on at the same time.
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I have 2 boards with split ppm. 1 with canbus.
The split ppm I run power and ground from 1 esc to the rx. Then split the ppm signal wire and run only the ppm wire to the other esc. This eliminates ground loops and double feeds. I would run can on all of my boards but I seem to have a knack for killing canbus chips. (3)flipshite, (2) neo boxes so far.
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Would I do something like this:
Cut the ground/neg and +5 so one vesc has all 3 connections and the other only has signal?
No; you want both ESCs connected to the same channel on the receiver.
Hmm so would I have one ESC connected to a single channel with the second ESC’s signal wire spliced onto the first esc signal wire and the +5 and ground snipped from the second esc?
Yes
Just run the white wire to the second ESC
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How about dual receivers in a different way. Say I have a Hoyt puck for board number 1 and a VX1 for board number 2.
Can board number two get a hoyt receiver and a VX1 receiver so I can take my pick of remote? I thought about hoyt receivers in both, just wondering if theres a solution for the situation where I want both but dont wanna buy two pucks