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Old 05-03-2018, 04:42 PM   #3224 (permalink)
thingstodo
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Quote:
Originally Posted by wootwootman View Post
This is one of my biggest fears, that I'll connect something backwards and have a light show. Since you were only using 56V, I think the IGBTs are fine. And as far as your capacitor goes, be sure to discharge it with a resistor before you charge it with the correct polarity. Idk what type you're using, but I have an SBE Power Ring 700D529 and I was told it's non-polarized so there shouldn't be a problem with it.
Yup - I have the *MONSTER* ring cap. It was discharged with the 5.6 ohm resistor when I realized my mistake. Thanks for the info that it is not polarized ... that's the big cost. The IGBTs are fine. They are definitely NOT polarized.

Quote:
I think we have different versions of the controller board (21), so I can't speak for yours, but nothing on the schematic jumps out to me as vulnerable to reverse polarity damage.
I was not worried about the control board. It is alternately connected to the high side and the low side through the driver only .. as fast as I can see anyway. And it is powered from a separate supply ...

It is the power section I am worried about. But I could be wrong.

Quote:
For my encoder issue, I read through the AD2S1210 datasheet and if I understand correctly, the resolution is currently set to 10-bit but I need it to be 12-bit. This should allow it to emulate a 1024-line encoder instead of a 256-line one (right?). I can achieve this by taking Pin1 from GND and tying it to 5V. I'll try this out and report back, in case anyone runs into a similar issue in the future with the 2013 Leaf Motor EM57 (resolver 34VRX-1004C01S)
10 bit is 0 - 1023 or 1024 pulses per revolution. 12 bit is 0 - 4095 or 4096 pulses per revolution. 256 (or 0 - 255) is 8 bit.

Tieing pins to GND or +5V is how you strap your chips to configure some of the simpler stuff. I use 1K resistors instead of jumpers ... just in case I have issues with current limiting somewhere!

If you add a link to the data sheet I can look at it as well - another set of eyes!

EDIT: Found this link http://www.analog.com/media/en/techn...s/AD2S1210.pdf and I think they messed up with the description of 10 bit. I think you want 10 bit = 1024.
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Last edited by thingstodo; 05-03-2018 at 05:29 PM.. Reason: Found a datasheet
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