VFD Update: AC retrofit to DC, Drive Start Up on DC bus.

I said I was going to wait until I had enough batteries to start this drive up but I decided I couldn’t wait. I took a 110VAC to 42VAC power supply that was lying around and fed that into the secondary of the fan transformer (690VAC tap). Through an undersized bridge rectifier I need to change out if I’m going to use it for longer than a brief start-up (400V, yes technically big enough but..). The drive started on it way up to 220VAC as the capacitors charged. I didn’t allow it to stay on long because I have no fan and I got a over temp alarm though, I think it’s not right, 110 deg C. I must have wiggled a cable out? I’ll look around as I think I know where both sensors are found.

So there it is, started up. I have a lot of reconfiguration to do to the drive to get it to run on low DC bus voltage. I was reading the manual and I think I can cheat it down…. I certainly don’t want a 680V DC bus as that’s a lot more batteries than I was planning on.  I haven’t decided if I’ll be running it by potentiometer, 0-10VDC or 4-20mA control signal … I should probably figure out how I’m going to physically request/actuate a speed demand before I decide.

Next steps: 1. Attach DC fans for the heat sink, provide a more securely wired input, configure settings…

Note: 110V  42VAC transformer fed to 110V480V transformer, rectified to supply to 220VDC. The VFD powers up in the 200V neighborhood.
Note: 110V 42VAC transformer fed to 110V690V transformer, rectified to supply to 220VDC. The VFD powers up in the 200V neighborhood.
Below is the 80W power supply board and then above that is the IGBT board with capacitors to the right.
Below is the 80W power supply board and then above that is the IGBT board with capacitors to the right.

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