@lidocaineus If you want to try to only replace the screen, I recommend that you make sure you can still BLE-connect to the Megan to make sure it’s alive.
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I noticed that in logs battery voltage isn’t split out for each ESC like currents, temperatures, duty cycle etc.
On Ankle Wreacher I have 4 VESCs wired individually, and was/am curious if I’m getting voltage drop across the wires between my G300s.
- Would it be possible to record individual voltages from each ESC?
- My Megan is connected over CAN. It is an average of all 4 reported voltages, or from a single vesc? Which one? (lowest CAN id or something?)
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I have found that vesc voltage readings are not completely accurate compared to the actual battery voltage and it makes me wonder if they would be accurate enough at all to calculate voltage drop?
I found they have like a ±0.5V gain error and I have voltage drops of easily 10V+ on the battery so it’s definitely good enough to record overall sag, but most of sag is in the batteries and internal connections, not in the output cables so I don’t think measuring multiple vescs really help anything here.
That said the voltage data is in the CAN packets if anyone wants to make a logger that records it.
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There’re also settings in Metr to smooth out battery voltage readings and margin. Not sure if that matters or not.
Megan does actually log the voltage for all ESCs. However, when we process the uploaded file, we only keep the voltage data from the first ESC – the first would be the one with the lowest CAN ID, yes. The reason for this is that for most people, all ESCs are connected to the same battery and thus the voltage is the same for all.
Your particular setup is special and I understand that for you specifically it would make sense to retain all voltage values.
This is a tough call to make. It’s not a difficult update to make if we just keep all voltages for everyone. But then we need to store all those redundant values that almost nobody will ever use. Or we can create a config option but then it’s not a simple update anymore.
Let me discuss this with Roman. No promises at this point.
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So how did that turn out anyway? Is there a integration with race chrono?
Unfortunately not. This was too low prio.
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Id record voltages with a different dedicated device. Vesc suuuucks at tracking voltage
Thanks for the reply
Live long an prosper 
So @janpom, I looked into this more with TITS, where I can log stuff.
Here’s a chart of the voltage from a couple minutes of racing.
@Dinnye is totally right. My 4x G300s read up to 1.1v different at rest.
Subtracting out this static offset, all voltages remain within 0.1v of eachother, even when pulling 100’s of battery amps. Considering this is the resolution of the data in the CAN packet, literally couldn’t be closer.
TLDR; there’s no appreciable difference in the voltage at the 4 vescs
Pending an even weirder setup then mine, I now think individual voltage logging is entirely unnecessary 
would likely only cause confusion to users (from the static offsets). Thanks for humoring me 
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I wonder if it is hardware dependent. Like my mp2 escs have the most reliable motor detection values and my flipsky the least reliable. For motor detection battery voltage plays a role, so i guess mp2 is more accurate
My m6d hobby charges have a (hidden) calibration menu, and they weren’t all calibrated the same when I got 'em. i make a large assumption from that that anything else measuring voltage needs calibrating, and can therefore vary device to device.