MotionMaster Upgrade

Hey, you are spot on. I realized this late last night as well. The manuals confirm that this series of drives are designed for 120V inputs.I also confirmed that the power supply going to the chassis is a 277V (single leg of 480-3) so it must be that there is a voltage drop, and then, a rectifier before the capacitor. I attached the picture for today's work, but I think there is an SCR directly below the cap, and to its right is the rectifier. I was expecting a transformer and completely missed the SCR hidden behind the wires. I'm trying not to change the wire layout until I am more comfortable, but I think I am getting there. 

So I think the drives have: DC in, DC out, tach, reset/enable and 10V command. 

I do not believe there is a bridge rectifier. I think its just an SCR and then a couple of diodes. Will take apart the wires and check today but I am getting more and more confident that if I identify the 120V input (native to the SD chassis, without the 480V single leg add on) I should be able to connect 120V to it and make it work. Just need to find me a box of 100W lightbulbs.

Update on this:
(a) I have connected 220v power to the machine and have confirmed that the drives and servos all work. I will be able to use this machine in its entirely with 220v single phase input on 12HP spindle (will run it at 4hp max) and run all the drives  (8 of them, XYYZ, AA BB). These old amp drives were set up to run the DC brushed servo at max rpm if the signals (10V,tach,EN) were all OPEN - sort of insane. Thankful I had the foresight to disconnect the ballscrews from the servos. I don't have workspace - working ON the bed of the machine with the controller. See pic. Could have been a final destination sort of outcome. 

(b) Hunted down faulty monitor display to a few bad connections and once those were fixed, my LCD display is actually perfectly good, this allowed me to actually test out the machine's ability to work. The linuxcnc mindhive (grumpy old dudes who have forgotted more shit than I will ever learn) helped me out immensely like with everything else. Have to look at the fagor 8055 manual to understand what to expect from triggering the limit switches but other than that, I have a big functioning CNC router. There is some weird stuff going on which I do not understand - the servos are not paired corrected, meaning, moving "controller Y" physically turns one X servo and one Y servo. A few wires need to be fixed and I need to make sure stuff turns in the right direct and get synced and what not. Maybe its a controller setting. I have no intention of using the Fagor controller and will likely not waste time on it. 

(c) Mechanically, Y axis is good. Z axis is good. the X-axis is "grinding". Will remove rust with neutralized citric acid and starch to get me a chelating paste. and repack the bearings on the X axis. I hope it is not a bad ball screw. The blocks that glide on the linear rails are these things that have 2 rows of bearings that slide along the groove. I have no experience whatsoever with these. Any and all tips super appreciated.

(d) Ordered my 5in rotaries. Found this design where the 5in chuck is connected to a wormgear with 20:1 reduction. backlash (10arcs) seems acceptable. The reduction gives me holding power that will all but eliminate any issues with holding the word steady. Adding up the 2 chucks, I'll have in the region of 200Nm of torque on my work pieces. Happy about this. 

(e) Gambling that it will be OK to hang 200lbs off the gantry for the swivel head + spindle. Found some implementations of this with older heavier hardware so I'll take my chances. I might have to upgrade the air balancer, or add a counter weight to the gantry. In any case, its too late. Stuff is ordered and they don't do refunds.

(f) Fun times. The entire manual for my spindle contains one single word of English. It says No! on page 19. See attached. Everything else is in Chinese that I can't read. Hopefully AI translation is decent. Same company with spindle and swivel head. Very happy to have found them. Not pushy. Don't give bullshit answers. Take pride in explaining stuff in engineering speak. Feels like a bunch of guys trying to make the best damn product they are capable of making.

Some questions that remain:
I wonder if I can reuse the dynamic brake and reactors. They are rated for the amperage that I will use with my 9kw spindle. I don't see why not, but I do not know for sure. I also don't understand from first principles what a reactor does. I think they are inductors to smooth out ripples in the outgoing current from VFD to spindle.

Grease. What should I use? I wanted to change the color of the grease so I know which lines are blocked, but someone cautioned against mixing stuff.

Ball bearings. Should I just put new ones in while I'm at it, or, do they last a lifetime? Do I caliper them? Is it even meaningful to? Surely the precision needed would be far more than my 0.02mm caliper. 

July 4th. This has to make a chopstick by then.
 

If they're upstream of the VFD they're called 'line reactors' and smooth out incoming power ripples.

If they're downstream they're called 'load reactors' and smooth out the power to the motor.  Reduces heating in the motor, especially useful for older motors which aren't rated for VFD use and which are going to be run at speeds lower than nameplate rating.

Grease - you can flush out all the greased components with kerosene, then blow out excess with air, then regrease with whatever flavor you want.  Disconnect each grease circuit and flush each component separately - this will help identify any clogged or broken lines.  When you've cleared all the individual circuits out, flush any manifolds and header lines.

Could be from a number of sources.  Suggest disconnecting the ballscrew nut (or nut mount) from the X-carriage.  This will allow you to move the carriage by hand, as well as rotate the ballscrew in it's bearings, and also the nut on the ballscrew.  Should help you identify the source of crunchiness.

Which bearings?  Your machine has quite a few.  Some are cheap, some are not.  Your wallet will determine what you can replace... but if the bearing is easily replaceable and remotely suspect, I'd replace it.  You can usually find NOS name-brand bearings on ebay for decent prices.