[mflux_gamblej]

I have been getting errors on my big fadal the 4020. it has a baldor H2 vector drive, 20hp. I have been running both that machine and a 5hp vmc20 on my RPC which is 20hp. I am also running a 5hp compressor on that same circuit. I was surprised that it worked at all, but i measured current draws and I am using 80% in a worse case scenario even with some head room added to my calculations.

At any rate, today it is hot here. I bet it is getting to 100F in my shop. I don't have Air con there. Maybe I'll buy an air con here soon. I am getting 'DC BUS LOW' errors on my baldor H2 drive. When that happens the spindle coasts to a stop and the control shows various errors indicating that the spindle drive isn't communicating.

This is irritating considering I was running the whole lot the other day and it wasn't exactly cold in my shop then, maybe 80F. But today the baldor H2 isn't happy. It seems to throw an error when the air compressor is running. So I do think it may have something to do with loading or heat or both. There may be additional load on my local circuits today too from everyone around running their AC's.

At any rate, my RPC voltages are 240, 228, and 219. Thats within 8% balanced. I cant say if it has always been that way or not. I do have my fadal's transformer tapped for lower voltages on those two legs already. any thoughts?

[mflux_gamblej]

to follow up on this, it was my fault.

I had re-tapped the transformer a year or so ago. I guess I got a little dyslexic reading the chart on the transformer cabinet door. I had my transformer tapped for 270V all three phases. I run an RPC, it makes 230V or so as stated here previously. This time I re-tapped the transformer and measured the voltages at A12-B12-C12 (the lines that feed the inverter). they are all 230V +/- 10V now as spec'd out in the maint. manual.

geeze.

working fine now. why it didn't complain previously I really have no clue.

[R7237]

This may be a dumb question and know it is an old thread, but hope you can answer my question. Off of your RPC, does it matter the location of the L1 L2 and L3 lines into the 4020? I am having some strange issues with the spindle and wonder if it is a phase issue. Thanks in advance.

[mflux_gamblej]

This may be a dumb question and know it is an old thread, but hope you can answer my question. Off of your RPC, does it matter the location of the L1 L2 and L3 lines into the 4020? I am having some strange issues with the spindle and wonder if it is a phase issue. Thanks in advance.

please reference the fadal manuals. in some situations when you reverse the phase the motor will just spin the wrong way, then you simply switch any two of the phases to get it right. In my experience with other machines when phased wrong other things can happen (this was on a DC spindle SCR drive type machine though). on the fadal either it wont matter at all because the raw AC power gets rectified by the inverter anyhow right off the bat, or the motor will spin the wrong way then you switch it around.

to get your phases 'right' just hook up a 3ph AC motor, get it to spin how you want it to, then label U,V,W right at the breaker panel and keep the color code the same throughout your shop. In my case the colors are Red White Black and Green (or bare copper). and all my machines are hooked up in that color order just for consistency.

Be careful in those panels - best of luck.