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Old 05-03-2018, 11:38 AM   #3222 (permalink)
thingstodo
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Results for May 2

Quote:
Originally Posted by thingstodo View Post
I still can't figure out why the controller is not putting out current when I move the throttle signal. Weird.
Umm ... .. I seem to have reversed the polarity of the battery pack.

The DC converter is powered by a separate small 12V battery, it is correct and powers up the control board correctly.

The DC+ bus was at 0V and the DC- bus was at 56V. Perhaps that had something to do with WHY the controller would not put out any AC to the motor? I would think that the gate signals to the IGBTs would have been the wrong voltage to allow current flow? And THIS is why the run-pi-test didn't appear to do anything?

Paul - did I break the controller? Is there anything polarity sensitive on the DC bus side of the controller? If the ring capacitor failed, I would expect a short circuit and many obvious bad things ... but I didn't even notice a spark ... it was pre-charged through a 5.6 ohm resistor up to 47 or 48V then I closed a breaker manually (I don't have the contactors set up properly for pre-charge from the controller)

No smoke. No heat. No black marks. Just a nin-com-poop that should not play with controllers after working all day ... without some Adult supervision!

I knew that my attention span was getting worse ... I guess I didn't realize just how bad it could get. Routing the battery cable extensions (I bolted the battery cables to the existing Polaris AC controller lugs) took maybe 3 minutes each - remove the bolts, add the battery cable extensions, route the cables nicely through the rest of the rat's nest of cabling, put the bolt back on. And in that short time I managed to reverse B+ and B- !!!!!

Planning to power up and try running the controller and motor tonight, with the old firmware and motor settings, just to see if it does anything. Unless I'm told that there is no point and I broke the whole thing.

With the wrong settings, I don't expect the motor to run well, but I expect the motor to try turning ...

Posted as a reminder to triple-check what you are doing. Perhaps I will make a check-list of important stuff before I begin, and verify it after I finish, before I power it up. I sort of did this informally before. Now I think the priority has been raised quite a bit!
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