Difference between Single channel and AB encoder mode

[Roadstercycle]

OK, Here you go, I am trying to find an answer as to what is the difference between running the encoder in A/B mode and running in single mode. The reason I ask is because somewhere along the line, I believe it was in the last motor software update (I'm not completely sure about that) my encoder got changed to single mode. So the other day Jon Volk noticed it and said I should be in A/B mode. Damien chimed in and said that nobody should be in single mode. What's really weird is that a lot of people even Damien has said that they are getting jerkiness when starting off slowly and can not seem to clean it up. My setup is smooth and clean starting, running and is a rocket ship until I switch to A/B mode. Then I get the slow speed jerkiness and it does not feel smooth. Switch back and it's fine. So what am I hurting or going to hurt if anything in single mode? I keep switching back to A/B and checking to see if I'm just imagining the jerkiness but I'm not, it does really make a difference. I don't suggest anyone doing this as I don't know the ramifications if any.

[arber333]

OK, Here you go, I am trying to find an answer as to what is the difference between running the encoder in A/B mode and running in single mode. The reason I ask is because somewhere along the line, I believe it was in the last motor software update (I'm not completely sure about that) my encoder got changed to single mode. So the other day Jon Volk noticed it and said I should be in A/B mode. Damien chimed in and said that nobody should be in single mode. What's really weird is that a lot of people even Damien has said that they are getting jerkiness when starting off slowly and can not seem to clean it up. My setup is smooth and clean starting, running and is a rocket ship until I switch to A/B mode. Then I get the slow speed jerkiness and it does not feel smooth. Switch back and it's fine. So what am I hurting or going to hurt if anything in single mode? I keep switching back to A/B and checking to see if I'm just imagining the jerkiness but I'm not, it does really make a difference. I don't suggest anyone doing this as I don't know the ramifications if any.

I ran my motor quite some time in single mode. Maybe 3yrs? Last couple of years i run ACIM in A/B mode and from user standpoint it is generally smoother and less error prone. I can restart into rotating motor uphill with A/B and inverter doesnt mind. But for this jerkiness in slow speed i must say it has not changed from A to A/B mode. I think its dependent on control loop and filters settings....

In rev2 to operate in single mode you need to use the channel A with its RC filter unchanged. But you have to depopulate RC filter from channel B and Z and feed Z channel directly to A behind filter. This will mirror signal A to channel Z and is a fault elimination of some kind.

So if you can use both options with no adverse effects i would say you are lucky and keep using single channel. I didnt find anything wrong with it when i was on it at the time. Maybe it was even easier to troubleshoot. But it wasnt like i had a choice .